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Evaluation of Environmental Load Reduction Effect of Plastic Containers

and Packaging Recycling Methods and Energy Recovery (LCA)

March 2019

Japan Initiative for Marine Environment (JaIME) Consignee: Plastic Waste Management Institute

Introduction

During the G7 Charlevoix Summit held in Canada on June 9, 2018, the United Kingdom, France, Germany, Italy,

Canada, and the European Union (EU) have signed the ‘Ocean Plastics Charter’ (the US and Japan did not sign the

Charter), which is aimed at strengthening plastic regulations in each country and stipulates measures on the reuse,

recycling, and utilization as heat source of plastic products. Also, recently, industry players are coming out with

initiatives on plastic use, for example, Unilever has announced its targets for the use of recycled materials, and

McDonald’s has announced that it will stop using plastic straws in all its restaurants in the UK. Further, the

European Commission, the European Investment Bank (EIB), the World Wide Fund for Nature (WWF), and The

Prince of Wales International Sustainability Unit have formulated the Sustainable Blue Economy Finance Principles

for a sustainable marine economy and are gathering signatories among major institutional investors. From these, we

can see that the growing problem of marine plastics is spurring the international movement of recycling plastic

resources.

In Japan, through the Fourth Fundamental Plan for Establishing a Sound Material-Cycle Society (June 19, 2018

Cabinet decision), the “Resource Circulation Strategy for Plastics” was formulated, the promotion of measures

based on the strategy was stipulated, and the Subcommittee on Resource Circulation for Plastics was established

within the Central Environment Council Committee on Sound Material-Cycle Society.

In response to the above international and national initiatives, the Japan Initiative for Marine Environment

(JaIME) have been launched on September 7, 2018 with co-secretariats of five chemical industry associations in

Japan; namely, the Japan Chemical Industry Association, the Japan Petrochemical Industry Association, the Vinyl

Environmental Council, the Japan Plastics Industry Federation, and the Plastic Waste Management Institute, to

pursue activities under four action plans.

Action Plans of JaIME

(1) Collect and analyze information and promote information sharing

(2) Take appropriate and timely actions to the domestic and global movements

(3) Engage in supporting Asia activities in this field

(4) Promote capacity building for scientific knowledge and evidences (LCA)

As a concrete initiative to (4) promote capacity building for scientific knowledge and evidences (LCA), JaIME

has conducted objective and scientific evaluation and comparison of the environmental load (CO2 emissions and

energy resource consumption) reduction effect using life cycle assessment (LCA) method in regard to plastic

containers and packaging recycling methods and energy recovery.

To carry out the evaluation, JaIME consigned the services of the Plastic Waste Management Institute (PWMI),

and a working group to handle the evaluation was established within PWMI. Members of the working group are

listed in the next page.

The evaluation by LCA was carried out by adopting new knowledge and using the report on evaluation by LCA

conducted by the Japan Containers and Packaging Recycling Association (JCPRA) in June 2007 (Report on the

Study of Environment Load of Plastic Containers and Packaging Recycling Methods) as basis. In particular, the

environmental load (CO2 emissions and energy resource consumption) reduction effect of different waste processing

methods was calculated for 1 kilogram of used plastic containers and packaging discarded from homes. Evaluation

and comparison of the processing methods have shown that energy recovery is not environmentally inferior to

mechanical recycling and feedstock recycling and is an effective method for processing of plastic containers and

packaging.

The preparation of the report for the LCA evaluation and its results was consigned to the Mizuho Information &

Research Institute, Inc.

We would also like to express our sincere gratitude to the Japan Containers and Packaging Recycling Association

for their enormous support and cooperation in the conduct of evaluation by LCA through advice regarding LCA

computation methods and provision of pallet data.

March 2019

Japan Initiative for Marine Environment (JaIME)

Consignee: Plastic Waste Management Institute

Working Group on Evaluation by LCA of the Effectiveness of Energy Recovery

(Period: November 2018 to March 2019)

(Titles omitted)

Chairperson: Kiyotaka Tahara, Director, Research Laboratory for IDEA, National Institute of Advanced Industrial

Science and Technology (AIST)

Vice-Chairperson: Jun Nakatani, Assistant Professor, Urban Resource Management Laboratory, Department of

Urban Engineering, the University of Tokyo

Members:

Mitsufumi Ono, General Manager, Chemicals Management Department, Japan Chemical Industry Association

Toshio Yokoyama, Director, Administration/Environment Group, The Japan Plastics Industry Federation

Toshiyuki Niitsu, General Manager, Service & Coordination Division, Japan Petrochemical Industry Association

Kentaro Yamaguchi, General Manager, Service & Coordination Division, Japan Petrochemical Industry Association

(November 2018 – February 2019)

Yuji Nagano, Deputy General Manager, Service & Coordination Division and Planning & Research Division, Japan

Petrochemical Industry Association (March 2019)

Tadashi Naganawa, General Manager, Technical Department, Vinyl Environmental Council

Investigation Consignment:

Hiroyuki Uchida, Senior Consultant, Environment and Energy Division 2, Mizuho Information & Research Institute,

Inc.

Fumiya Mori, Consultant, Environment and Energy Division 2, Mizuho Information & Research Institute, Inc.

Shuji Naito, Consultant, Environment and Energy Division 2, Mizuho Information & Research Institute, Inc.

Shotaro Nakanishi, Consultant, Environment and Energy Division 1, Mizuho Information & Research Institute, Inc.

Secretariat:

Hiromi Fukuda, General Manager, Administration and Information Service Department, Plastic Waste Management

Institute

Akihiro Izumi, General Manager, Surveys and Research Department, Plastic Waste Management Institute

Junichi Nakahashi, LCA Advisor, Plastic Waste Management Institute

Contents

1. Purpose of Evaluation .............................................................................................................................................. 1 2. Target of evaluation and study ................................................................................................................................. 4 3. System boundary points ........................................................................................................................................... 8

3.1 General principle for deciding system boundary points .................................................................................... 8 3.2 Parameters for each method .............................................................................................................................. 9

3.2.1 Mechanical recycling .................................................................................................................................. 9 3.2.2 Feedstock recycling .................................................................................................................................. 13 3.2.3 Energy recovery ........................................................................................................................................ 21

4. Setting of assumptions and conditions .................................................................................................................. 24 4.1 Composition ratio of plastic containers and packaging ................................................................................... 24 4.2 CO2 emissions settings .................................................................................................................................... 27 4.3 Setting of assumptions and conditions for evaluation ..................................................................................... 35

5. Inventory data for each processing method ........................................................................................................... 36 5.1 Mechanical recycling ....................................................................................................................................... 36

5.1.1 Handling of residues ................................................................................................................................. 36 5.1.2 Returnable pallet (substitute for new resin) .............................................................................................. 41 5.1.3 Returnable pallet (substitute for new wood) ............................................................................................ 53 5.1.4 Recycled resin (compound) ...................................................................................................................... 56

5.2 Feedstock recycling ......................................................................................................................................... 60 5.2.1 Liquefaction .............................................................................................................................................. 60 5.2.2 Gasification (ammonia production) ......................................................................................................... 64 5.2.3 Gasification (combustion) ........................................................................................................................ 68 5.2.4 Blast furnace reduction (substitute for coke) ............................................................................................ 71 5.2.5 Blast furnace reduction (substitute for pulverized coal) ........................................................................... 82 5.2.6 Coke-oven chemical material ................................................................................................................... 85

5.3 Energy recovery ............................................................................................................................................... 90 5.3.1 RPF use ..................................................................................................................................................... 90 5.3.2 Cement calcination ................................................................................................................................... 96 5.3.3 Incineration with power generation ........................................................................................................ 102

6. Graphic representation of CO2 emissions and CO2 emissions reduction effect for each processing method .... 108 6.1 Graph of CO2 emissions and CO2 emissions reduction effect for each processing method ........................ 108

6.1.1 Mechanical recycling .............................................................................................................................. 108 6.1.2 Feedstock recycling ................................................................................................................................ 110 6.1.3 Energy recovery ...................................................................................................................................... 114

6.2 Graphic representation of CO2 emissions and CO2 emissions reduction effect for each processing method117 6.2.1 Mechanical recycling .............................................................................................................................. 117 6.2.2 Feedstock recycling ................................................................................................................................ 119

6.2.3 Energy recovery ...................................................................................................................................... 124 7. Analysis ................................................................................................................................................................ 127

7.1 Proportion of environmental load reduction effect for processing of residues in recycling through

mechanical recycling methods................................................................................................................................. 127 7.2 Analysis of environmental load reduction effect due to differences in bale composition ............................ 131

8. Summary .............................................................................................................................................................. 137 9. Future issues ......................................................................................................................................................... 143

1

Purpose of Evaluation

Purpose and concrete initiatives

The purpose of the evaluation presented here is to objectively and quantitatively evaluate and compare

the environmental load reduction effect of specific recycling methods (mechanical recycling and feedstock

recycling) and energy recovery. In this report, we refer to recycling methods and energy recovery

collectively as “processing methods.”

In particular, the evaluation was carried out based on the report on the evaluation by LCA conducted by

the Japan Containers and Packaging Recycling Association (JCPRA) in June 2007 (Report on the Study of

Environment Load of Plastic Containers and Packaging Recycling Methods; hereinafter, “2007 JCPRA

Report”) and adopting new knowledge to calculate and compare the environmental load (CO2 emissions

and energy resource consumption) reduction effect of each processing method based on 1 kilogram of used

plastic containers and packaging materials* discarded from homes.

*Definition of plastic containers and packaging materials (hereinafter also referred to as “plastic

containers and packaging”) covered in the evaluation

According to the Containers and Packaging Recycling Act, “containers and packaging” refer to

“containers” in which merchandise is placed and “wrapping” materials in which merchandize is wrapped,

and that become unnecessary once the merchandise has been consumed or otherwise separated from them.

Containers and packaging materials that must be recycled under the Act (those that are targeted for

selective collection) include glass containers, PET bottles, paper containers and wrapping, and plastic

containers and packaging materials. This report pertains to the evaluation of processing methods

specifically for plastic containers and packaging materials.

*Overview of the processing (mechanical recycling, feedstock recycling, and energy recovery) of

plastic waste in Japan

To enable a deep understanding of the evaluation by LCA mentioned in this report, we provide an

overview of the processing of plastic waste in Japan in Table 1-1.

Among plastic containers and packaging included in general waste (municipal solid waste), those plastic

waste that can be selected and separated as single-resin material without impurities, such as PET bottles

and white styrene foam trays, are suited for mechanical recycling and feedstock recycling, and can produce

high-quality recycled products at high yield.

Also, plastic containers and packaging that are selectively discarded as recyclable waste from homes are

mixed plastic that are effectively used as materials for mechanical recycling and feedstock recycling.

However, unlike the single-resin materials mentioned above, they are mixed resin materials and include

impurities, wherein approximately half of the material cannot be converted as products through mechanical

recycling and therefore end up as residues. These residues are used as materials for energy recovery, such

as use as refuse-derived paper and plastics fuel (RPF use), cement calcination, and incineration with power

generation.

2

On the other hand, due to the difficulty of removing or separating food residues, some of the plastic

waste discarded from homes as municipal waste (combustible and incombustible waste) are discarded

among many other wastes other than plastic and are not suitable for processing through mechanical

recycling and feedstock recycling. Thus, they are processed and disposed through energy recovery, such as

through incineration with power generation and incineration with heat utilization.

As can be seen from the above situation, energy recovery is carried out as one of the methods for

processing of various types of plastic, such as those mixed with non-plastic materials (food residues, etc.)

or those discarded as part of non-plastic materials. (Landfilling, which does not involve incineration, is

difficult to carry out in Japan due to its limited land area and for sanitary reasons.)

Table 1-1. Overview of the processing of plastic waste in Japan

Amounts in *1, *2, *3, and *4 are data from JCPRA; Volume of mechanical recycling of general waste by JCPRA is 680,000 tons, which is higher than the total of *1, *3, and *4.

Scope of public disclosure

The results of this evaluation are intended for the general public.

Comparison method

Comparison was conducted using the basket-of-products method. For comparison, we conducted a

“standardization of functional unit,” which ensures the substitutability of existing products either by

products that use recycled products (products obtained through recycling) or by virgin materials and

resources. We set the parameters for standardization of functional unit for products that use recycled

products and substituted products based on the 2007 JCPRA Report.

3

Definition of terms used in the comparison system

In the comparison system, “recycled products” are defined as products produced through recycling, and

“products using plastic containers and packaging” are defined as products that are processed and formed

using “recycled products” as material. The flow of steps for products using plastic containers and

packaging is referred to as the “recycling system.” On the other hand, existing products that may be

substituted by “products using plastic containers and packaging” are referred to as “original products,” and

the flow of steps to produce them is referred to as the “original system.”

The environmental load reduction effect was then calculated from the difference between the recycling

system and the original system for each of the processing methods.

4

Target of evaluation and study

Targets of processing

The evaluation was conducted using plastic containers and packaging materials (“plastic containers and

packaging”) as targets. Although plastic containers and packaging are usually used for mechanical

recycling and feedstock recycling, energy recovery through RPF use and cement calcination was also

evaluated as an alternative method for processing of plastic containers and packaging. Further, since

incineration with power generation is a method used for processing of municipal waste, it was also

evaluated as a method for processing of plastic containers and packaging as part of municipal waste.

Processing methods evaluated

Methods included in the 2007 JCPRA Report.

The 2007 JCPRA Report used the processing methods, products using plastic containers and packaging,

and substituted products as shown in Table 2-1.

Table 2-1. Processing methods, products using plastic containers and packaging, and substituted products

included in the 2007 JCPRA Report

The suitability of including the same methods and products as with the 2007 JCPRA Report was

determined in consideration of the current situation.

5

Typical products from mechanical recycling

The following graph shows the proportion of different uses for mechanical recycling products in fiscal

year 2017.

Figure 2-1. Proportion of mechanical recycling products according to use

(Source: JCPRA website)

The above figure shows that pallet and recycled resin account for the largest proportion and are the

typical products of mechanical recycling. Plastic sheet, which was included in the 2007 JCPRA Report,

accounted only for 1.4% as of 2017, showing that it has almost ceased to be produced through recycling,

and was therefore excluded from this study. Mechanical recycling, however, is still included in this study as

a method for recycling.

In regard to pallets, the 2007 JCPRA Report included the evaluation of one-way pallet (substitute for

new resin and substitute for new wood) and returnable pallet (substitute for new resin and substitute for

new wood). Since the publication of the report, however, JPCRA has revised the pallet amount and targets

for evaluation through the “FY2016 Update of inventory data for environmental load reduction effect of

recycling of plastic containers and packaging” issued in January 2017. As such, in this study, we revised the

pallet settings based on the above update and included only returnable pallet in the evaluation. Details of

the revised pallet settings are given in Section 5.1.2.

Since recycled resins are recycled pellets, which are intermediate products, they are different from pallets,

and were therefore not included in the comparison with other methods, although their environmental load

reduction effect was measured.

Typical products of feedstock recycling.

The following graph shows the sales volumes for different processing methods for feedstock recycling

from fiscal year 2011 to 2017.

6

Figure 2-2. Proportion of feedstock recycling products according to use

(Source: prepared based on JCPRA website)

Feedstock recycling is carried out typically using blast furnace reduction, coke oven chemical material,

and gasification. Although no sales have been reported for liquefaction in recent years, since it remains as a

processing method for plastic containers and packaging, it was included for evaluation in this study.

Evaluation in the 2007 JCPRA Report, however, was conducted based on the case of a plant in Sapporo,

which is a cold weather region, hence, the evaluation was affected by a significant loss of energy. On the

other hand, efficiency may be higher for a plant built in warm weather regions, pointing to the need for

careful interpretation of the evaluation results.

Typical methods for energy recovery

The following table shows the proportion of different methods for energy recovery in fiscal year 2017.

Table 2-2. Proportion of energy recovery recycled products by method (2017)

(Prepared based on PWMI “Flowchart of Plastic Products, Plastic Waste and Resource Recovery”)

Although the above table shows that incineration with heat utilization has been used for regional heating

or for heating pools, it was excluded from this study due to the difficulty of obtaining thermal efficiency

data. As such, evaluation of energy recovery was only done for incineration with power generation, RPF

use, and cement calcination.

0

50,000

100,000

150,000

200,000

250,000

2011 2012 2013 2014 2015 2016 2017

Sale

s vol

ume

(t)

Blast furnace reducing agent Coke-oven chemical material Gasification (Ammonia production)

Gasification (Combusion) Liquefaction

7

Summary of processing methods targeted for evaluation

The methods and products targeted for evaluation for mechanical recycling, feedstock recycling, and

energy recovery were decided based on (a) to (d) above, and are shown in the table below.

Table 2-3. Processing methods and products targeted for evaluation

8

System boundary points

3.1 General principle for deciding system boundary points

In the 2007 JCPRA Report, the input of plastic containers and packaging compliant to sorting standards

(hereinafter, “bale”) was set as the system start point, and the disposal of recycled products as the system

end point. Since this study, however, is aimed at comparing the environmental load of methods for

recycling plastic containers and packaging and incineration with power generation for combustible waste

performed by municipalities, the system boundaries were extended by setting the point in time that plastic

containers and packaging are discharged from homes as the system start point.

However, since extension of the system boundary included selective collection and baling processes that

were not evaluated in the 2007 JCPRA Report, there was a need to collect additional data. For this purpose,

we referred to the results of the study on “Municipal collection and transportation model construction and

LCA analysis (2019)” conducted by the Plastic Waste Management Institute.

The above study evaluated the environmental load of collection, transportation, and processing of plastic

containers and packaging. The study incorporated collection and transportation processes not included in

previous evaluations by summarizing the status of implementation of collection, transport, and processing

in the 23 wards of Tokyo and 20 provincial cities, and evaluating the environmental load related to

collection and transport.

The environmental load for selective collection and baling related to the discharge of plastic containers

and packaging and municipal combustible waste according to the report of the above study is as shown

below.

Figure 3-1. Environmental load in selective collection and baling

Collection (selection)

Plastic containers and packaging Transport 1 Baling,

storage Transport 2 Recycling factory

[For plastic containers and packaging]


Transport 1 Baling, storage Transport 2

Input volume t 1.000 1.000 1.000 1.000

Energy resource consumption (MJ) MJ 349.5 248.7 557.5 109.2

CO2 emission kg-CO2 23.7 17.0 21.7 7.3

・・・

Note: The energy consumption and CO2 emission values are based on values for mechanical recycling and feedstock recycling methods in the 20provincial cities.

[For combustible waste]For incineration with power generation or simple incineration, it was assumed that plastic containers and packaging were collected, transported, and processed as combustible waste.

Note: The energy consumption and CO2 emission values are based on values for the 20 provincial cities.


Combustible waste (plastic containers

and packaging)Transport Waste processing

plant


Transport

Input volume t 1.000 1.000

Energy resource consumption MJ 28.0 56.0

CO2 emission kg-CO2 2.0 4.0

・・・

9

3.2 Parameters for each method

Mechanical recycling

System boundary

Recycled products refer to the final products such as pallets, etc. that are processed by operators and

entities using plastic containers and packaging. Since recycled products are intermediate products, it is

difficult to compare them with virgin resin. Therefore, we expanded the scope of pallets, etc. to include

products produced using plastic containers and packaging and set them as equivalent products. Other

succeeding use stages were then treated similarly to offset the differences with the original system, enabling

the extension of the system boundary to include the product use and disposal stages.

Pallet

・ In regard to pallets, etc., it was assumed that products produced using plastic containers and packaging

are used in the same way as substitute products during the use stage, and the scope was extended to

include the time until incineration, after the manufacture of recycled products and manufacture of

products produced using plastic containers and packaging. Since the product usage was assumed to be

the same, the use stage was omitted.

Recycled resin (compound)

・ Since recycled products (reduced volume products, etc.) generally have poor quality, they are usually

mixed with industrial plastic waste, which have high quality similar to virgin plastic, to improve

quality before recasting. After creating compounds by mixing with other resins, they are used either by

mixing with products of the original system or singly as raw material for final products. Since it is not

certain what the final products are, assessment was conducted by assuming different substitution ratios

for virgin materials. After the production process, assessment was conducted to include the time until

usage and disposal after manufacture of the final products, in the same way as the original system.

(Since recycled resins are intermediate products and are therefore different from the other products,

comparison with other methods was not done.)

Original system

・ Pallets: Included plastic virgin pallets and wood pallets.

・Recycled resin: Virgin resin was set as the original material. Since they are mostly handled by resin

manufacturers, resin products, i.e., PE and PP, were included. However, it appears that when

using recycled resin (compound) from plastic containers and packaging, the weight of the

final product is sometimes increased to make up for the lack of product strength, or the final

product is manufactured by mixing with new resin, i.e., that they are not always treated in the

same way as new resin. Therefore, we conducted assessment by considering factors such as

substitution ratio, or how much of the original product (new resin) can be substituted.

10

Functional unit and system boundary

One kilogram of plastic containers and packaging discarded from homes was set as the basic functional

unit for making comparisons between methods. Further, practical units were standardized to the functional

unit, in consideration of the attributes of the products used for the original system and the recycling system.

[Mechanical recycling (returnable pallet (substitute for new resin))]

Figure 3-2. System boundary for returnable pallet (substitute for new resin)

In the 2007 JCPRA Report, computations were done so as to erase the effect of industrial plastic waste

input, which were all indicated in the system boundary, making the system confusing. In this study, we

decided to determine the environmental load reduction effect from the production of pallet made from

100% plastic containers and packaging, without mixing with industrial plastic waste, to remove the

confusion. This has no effect on the environmental load reduction effect, which is based on difference

computation.

Recycling system

Incineration, landfilling

Original system

Materials(resin)

Crude oil resource collection

Pallet(C pcs.)b kg/pc.


D kg = C × b

Creation of product

(molding, etc.)

Materials production

PE+PP＝D kg

Bale input Sorting

Residue processing(energy recovery)

Shredding, grav ity sorting

Creation of product

(molding, etc.)

Pallet(C pcs.)a kg/pc.


1 kg

A kg A kg

TransportBalingCollection, transport

Plastic containers and

packaging 1 kg

Recycled product

Bale inputTransportBalingCollection,

transport


packaging1 kg

B kg

Incineration with power generation

RPF use

Cement calcination

*Practical unit standardized based on number of pallets (C pcs.)

11

[Mechanical recycling (returnable pallet (substitute for new wood))]

Figure 3-3. System boundary for returnable pallet (substitute for new wood)

[Mechanical recycling (recycled resin (compound))]

Figure 3-4. System boundary for recycled resin (compound)

In the 2007 JCPRA Report, the effect of recycling plastic containers and packaging was computed by

considering the input of new resin and industrial plastic waste in regard to the manufacture of products

from recycled resin based on the actual situation, and computations were done so as to erase the effect of

industrial plastic waste input. Since these were all indicated in the system boundary, the basis for

computation was confusing. In this study, we decided to determine the environmental load reduction effect

by assuming the production of recycled resin from 100% plastic containers and packaging, without mixing

with industrial plastic waste, to remove the confusion. Otherwise, we considered the substitution ratio (f) of

new resin with recycled resin only from plastic containers and packaging, as with the 2007 JCPRA Report.

This has no effect on the environmental load reduction effect, which is the result of difference computation.

Bale input Sorting Shredding,

gravity sortingRecy cled product

Creation of product(molding, etc.)

Pallet(C pcs.)a kg/pc.


Recycling system

1 kgA kg=f pcs.×a kg/pc.

*Practical unit standardized based on number of pallets (C pcs.)

Bale input


Original system

1 kg

Logging, import Incineration, landfilling

E kg=C pcs.×b kg/pc.

ProcessingRaw wood, lumber

Pallet(C pcs.)b kg/pc.

Trans-portBalingCollection,

transport


packaging1 kg

Trans-portBalingCollection,

transport1 kg

Plastic containers and packaging

D kg

A kg


B kg

Incineration w ith pow er generation

RPF use

Cement calcination


grav ity sortingRecy cled product Resin production Recy cled resin Incineration,

landfilling

Recycling system

1 kgA kg A kg



packaging1 kg

Bale input Incineration, landfilling

Original system

1 kg

Crude oil resource collection Incineration, landfilling

A kg×f

PE/PP(resin)


1 kg


A kg×f

* Practical unit based on substitution w ith compound (recycled resin) w eight and set as substitution ratio.


B kg


RPF use

Cement calcination

12

Handling of residues

In the case of mechanical recycling, residues make up almost 50%; thus, it is important to consider the

actual state of their processing in making assessments. The following graphs show the results for fiscal year

2008 and fiscal year 2017.

Note: The volume of plastic residues from mechanical recycling in FY2016 was 170,400 tons, which is 20 times the volume of residues from feedstock recycling of 8,568 tons.

Figure 3-5. Processing of plastic residues from mechanical recycling for FY2008 and FY2017.


Using the above results for fiscal year 2017 as basis, we determined the environmental load from

processing of residues from incineration energy recovery (incineration with power generation), conversion

to RPF (RPF use), and use as cement raw fuel (cement calcination). Since the details of processing for

“others” in the graphs are not known, the component was proportionally distributed among the other

methods, resulting in the following composition ratios for processing of residues.

Table 3-1. Composition ratio of processing of residues from mechanical recycling

Simple incineration Incineration with power generation RPF use Cement calcination Total

0.0% 21.4% 53.2% 25.4% 100.0%

13

Feedstock recycling

Liquefaction

System boundary

・ Generated oil is divided into light oil, medium gravity oil, and heavy oil, which correspond to naphtha,

A-class heavy oil, and C-class heavy oil, respectively. The scope of the system was set to include their

use as diesel fuel, boiler fuel, etc.

・ Since the amount of CO2 emitted in the final use stage of these products is the same as the carbon

content of the plastic container and packaging, computations were made by assuming that all the

carbon (C) content of the inputted plastic containers and packaging is converted to CO2.

Original system

・ The scope of the system was set to include the use (combustion) and disposal of substitute products

(A-class heavy oil, C-class heavy oil, etc.) as substitutes for generated oil.

[Feedstock recycling (liquefaction)]

Figure 3-6. System boundary for liquefaction

14

Gasification

・ Gasification may be used for producing (1) raw material for ammonia production (chemical material)

and (2) fuel gas (combustion).

System boundary

(Use as chemical material)

・ The system boundary was set to include the conversion of recycled products from gasification to

syngas and the production and use of ammonia (and carbonic acid by-product). Since the amount of

CO2 emitted in the final use stage of these products is the same as the carbon content of the plastic

containers and packaging, computations were made by assuming that all the carbon (C) content of the

inputted plastic containers and packaging is converted to CO2.

(Use only as fuel gas (combustion))

・ For fuel gas use, the system boundary was set to include until the use of the heat (product) from

gasification. Since the amount of CO2 emitted in the final use stage of these products is the same as the

carbon content of the plastic containers and packaging, computations were made by assuming that all

the carbon (C) content of the inputted plastic containers and packaging is converted to CO2.

Original system

(Use as chemical material)

・ The system for ammonia production without the input of syngas produced from plastic containers and

packaging was set as the original system. The use of ammonia and other products was treated based on

combustion of inputted material, as with the recycling system.

(Use only as fuel gas (combustion))

・ Since the insufficiency in coke gas can be addressed by reducing the raw material for heavy oil, etc.,

computations were made based on combustion of C-class heavy oil in a boiler and generation of the

same amount of heat from syngas.

15

[Feedstock recycling (gasification (ammonia production))]

Figure 3-7. System boundary for gasification (ammonia production)

[Feedstock recycling (gasification (combustion))]

Figure 3-8. System boundary for gasification (combustion)

Bale input

Gasification furnace/gas

cleaning

Residueprocessing

Ammonia production

Recycling system

1 kg

A kg



packaging1 kg

Ammonia

Carbonic acid


Original system

1 kg

Resource ex traction

Natural gas ex traction

Production


1 kg


packaging

B kg

Slag(roadbed material)

D kg

B kg

C kg

Ammonia production Ammonia

Carbonic acid E kg

Carbonic acid C-E kg


Materials production Roadbed material D kg

Ammonia production plant

Sorting Recy cled product(gas)


Purified gas from utility gas, etc.

Shredding

* Practical unit standardized based on ammonia weight.

Reduction and solidification

Bale input

Gasification, melting

Residue processing

Gas purification (desulfurization/drying)

Recycling system

1 kg

A kg



packaging1 kg


Original system

1 kg



1 kg


packaging

B MJ

Slag (roadbed material)

C kg

B MJ

Heav y oil

Sorting Recy cled product (gas) fuel use

Purification, etc.

*Practical unit standardized based on calorific value of gas.


Gas cooling, cleaning

Gas/fuel use


Materials production Roadbed material C kgShredding

16

Blast furnace reduction, coke-oven chemical material

System boundary

・ For blast furnace reduction of recycled products, system boundary was set to include the blowing of

pulverized coal, coke, and blast furnace reducing agent particles, which are recycled products from

plastic containers and packaging, and blast furnace reduction along with iron ore, and until the

production of pig iron.

・ For coke-oven chemical material, system boundary was set to include the input of coke-oven

chemical material particles, which are recycled products from plastic containers and packaging, into

the coke oven, until the manufacture of gas, coke, etc. Further, fluctuation of coal, etc. affected the

fluctuation, etc. of hydrocarbon oil inside the coke oven. The boundary here was set to include until

the use of these products. Although CO2 is emitted at the final stages when the gas, coke,

hydrocarbon oil, etc. from plastic containers and packaging are used as products, since this amount is

the same as the carbon content of the plastic containers and packaging, computations were made by

assuming that all the carbon (C) content of the inputted plastic containers and packaging is converted

to CO2.

Original system

・ For blast furnace reduction, the original system was set to include the fluctuations in amount of coke

(go back further to include raw coal and hydrocarbon oil), pulverized coal, and energy supply in the

oven until the production of pig iron in existing systems without the input of recycled products from

plastic containers and packaging.

・ Conventionally, manufacturers have treated blast furnace reduction as a method for coke substitution.

Therefore, we evaluated the substitution with raw coal for producing coke. Since substitution of

pulverized coal was also theoretically possible, it was also included in the evaluation.

・ For coke-oven chemical material, the system was set to include the input of raw coal, the

manufacture of coke, hydrocarbon oil, etc., and until the final use and disposal as products. Similar

to the case of plastic containers and packaging, CO2 is emitted at the final stages of use or disposal as

products for coke and other products produced from the input of raw coal, etc., and the final use

stages of these products were considered in the computation. As such, combustion of raw coal, etc.

inputted into the coke oven or blast furnace was considered even for chemical use.

・ The amounts of coke, hydrocarbon oil, and gas formation in the original system and recycling

system for coke-oven chemical material were the same as those in the 2007 JCPRA Report.

17

[Feedstock recycling (blast furnace reduction (substitute for coke))]

Figure 3-9. System boundary for blast furnace reduction (substitute for coke)

Collection, transport


1 kg

Blast furnace reducing agent

particles

A kg

Recycling system

*Practical unit standardized based on pig iron production volume.

Coke ov en

Blastfurnace


Iron ore

Coke

Hy drocarbon oil

Pig iron

Raw coalCoal resource ex traction

Purification, etc.

Coal resource ex traction

Baling Transport Bale input

Gas

Benzene F kgToluene G kgXy lene H kg

Light oil component

Tar component

Oil coke D kg

BTX separation

C-class heavy oil E kg

BTX separation

Benzene I kgToluene J kgXy lene K kg

Purification, etc.

Coal resource ex traction Oil coke L kg

B kg

C MJ

Residue processing(Energy recovery, etc.)


1 kg

Original system

Coke ov en Blast furnaceMaterials

production

Iron ore

Coke

Gas

Pig ironRaw coalCoal resource

ex traction

Purification, etc.


Simple incineration, residue landfilling

Collection, transport Baling Transport Bale

input

Hy drocarbon oil

Benzene F+I kgToluene G+J kgXy lene H+K kg

Light oil component

Tar component

Oil cokeD+L kg

BTX separation

C-class heavy oilN kg

B kg

M MJ

C-class heavy oilC-M MJ and E-N kg (liters)

18

[Feedstock recycling (blast furnace reduction (substitute for pulverized coal))]

Figure 3-10. System boundary for blast furnace reduction (substitute for pulverized coal)

Recycling system




packaging1 kg



particles

A kg

Blast furnace

Iron ore

Pig iron

Gas

B kg

C MJ

General coal (pulverized coal)

Coal resource extraction

Original systemPlastic

containers and packaging

1 kg



input

Purification, etc.


C-class heavy oil C-D MJ




Blast furnace

Iron ore

Pig iron

Gas

B kg

D MJ9.28 kg

Gas


19

[Feedstock recycling (coke-oven chemical material)]

Figure 3-11. System boundary for coke-oven chemical material



1 kg

Coke-oven chemical material particles

Residue landfilling

A kg

Coke ov en

Hy drocarbon oil

Coke


Gas

Benzene G kgToluene H kgXy lene I kg

Light oil component

Tar component

BTX separation

B kg

C kg

C-class heavy oil F kg

Oil coke E kg

Recycling system

*Practical unit standardized base on coke production volume.

Original system

Raw coal Coke ov en

Hy drocarbon oil

Coke

Gas

Benzene M kgToluene N kgXy lene O kg

Light oil component

Tar component

BTX separation

B kg

J kg

C-class heavy oilL kg

Oil cokeK kg




1 kg



input

Purification, etc.Crude oil resource collection

C-J (calorific conversion) and F-L kg


BTX separation

Benzene G-M kgToluene H-N kgXy lene I-O kg

Coal resource ex traction Oil coke E-kgPurification, etc.

Purification, etc.

20


In the case of feedstock recycling, handling of residues differs for liquefaction, gasification, blast furnace

reduction, and coke-oven chemical materials.

Liquefaction and gasification

For liquefaction and gasification, since the entire bale is inputted, it was assumed that metals that are not

effectively utilized are processed in landfills as residues.

Blast furnace reduction

For blast furnace reduction, as shown in Table 4-4, since residues make up approximately 23%, it is

important to consider the actual state of their processing in making assessments. The following graphs

show the results for fiscal year 2008 and fiscal year 2017.

Figure 3-12. Processing of plastic residues from feedstock recycling for FY2008 and FY2017.


Using the above results for fiscal year 2017 as basis, we determined the environmental load from

processing of residues from incineration energy recovery (incineration with power generation), conversion

to RPF (RPF use), and use as cement raw fuel (cement calcination). Since details of processing for “others”

in the graphs are not known, the component was proportionally distributed among the other methods,

resulting in the following composition ratios for processing of residues.

Table 3-2 Composition ratio of processing of residues from blast furnace reduction

Simple incineration Incineration with power generation RPF use Cement calcination Total

6.6% 11.3% 23.1% 59.0% 100.0%

21

Coke-oven chemical material

For coke-oven chemical material, as shown in Table 4-5, since all the plastics are effectively utilized, it

was assumed that metals are processed in landfills as residues.

Energy recovery

RPF use

System boundary

・ The bale transported into the plant cannot be directly inputted to the RPF production line in the same

way with what is done for industrial plastic waste, thus, it was assumed that the bale is sent to the

RPF line after unpacking, removal of metals and other foreign substance by manual sorting or

magnetic separators, and removal of PVC using optical sorting, etc.

・ For RPF, the system was set to include production and use as heat, i.e., until combustion and

conversion to CO2.

Original system

・ The manufactured RPF is solid fuel and is used in the paper industry, etc., but it had been

conventionally used as coal substitute for coal boilers, etc.

・ Thus, computations were made by assuming its use as coal substitute.

[Energy recovery (RPF use)]

Figure 3-13. System boundary for RPF use

Recycling system

Original system

*Practical unit standardized based on calorific value of RPF, with a consideration of boiler efficiency, etc.



1 kg


RPF production

Incineration disposalA kg

RPF B kg（C MJ/kg）


1 kg



input

Coal resource extraction CoalPurification,

etc.D kg（E MJ/kg）* D x E x 0.9 = B x C x 0.88 (From 2007 JCPRA Report)

22

Cement calcination

System boundary

・ Pre-processing is the same as with RPF use.

・ Evaluation was therefore made by assuming the processing through primary crushing and secondary

crushing devices for cement calcination, after adding the bale sorting and other pre-processing

devices.

・ The system was set to include the secondary crushing for cement calcination, its use as heat, i.e.,

until combustion and conversion to CO2.

Original system

・ For cement calcination, computations were made by assuming its use as coal substitute as with RPF

use.

[Energy recovery (cement calcination)]

Figure 3-14. System boundary for cement calcination

Recycling system

Original system

*Practical unit standardized based on calorific value of cement raw material (secondary-crushing plastic).



1 kg


Cement calcination pre-processing

Incineration disposalA kg

Secondary-crushing plastic B kg（C MJ/kg）


1 kg



input

D kg（E MJ/kg）※D×E＝B×C


etc.

23


For incineration with power generation, unlike the methods mentioned thus far, evaluation was made

based on a case wherein plastic containers and packaging discarded from homes are collected as municipal

combustible waste and inputted into waste-to-energy power generation facilities. Power generation

efficiency was set to 12.81%, which is the average power generation efficiency for waste incineration

facilities according to the Ministry of the Environment “State of Discharge and Treatment of Municipal

Solid Waste (FY2016).”

System boundary

・ The system was set to include the direct incineration and power generation from plastic containers

and packaging, i.e., until combustion and conversion to CO2. The power used at waste-to-energy

plants was assumed to be supplied from the generated power.

Original system

・ The original system was based on a case of using the power sent to the grid after subtracting the

amount used within the plant from the generated power.

[Energy recovery (incineration with power generation)]

Figure 3-15. System boundary for incineration with power generation



1 kg


efficiency 12.81%Power

Incineration residue landfilling

A kg B kWh

Recycling system


1 kg


Grid powerPurification, etc.

B’ kWh

Original system

Resource extraction

*Practical unit standardized based on generated energy.

With the exclusion of component used within the plant.

Power plant


24

Setting of assumptions and conditions

4.1 Composition ratio of plastic containers and packaging

The component ratio of bale from plastic containers and packaging differs among municipalities. In

regard to this discrepancy, since the times of actual measurement of bale composition obtained from the

2007 JCPRA Report were different, rather than obtaining the average, we adopted the results from data

around the same period, namely, from the survey conducted by the former Plastic Management Research

Association for 2004-2006.

For this report, we conducted evaluation by adopting the bale composition based on the JCPRA

“Demonstration experiment on plastic containers and packaging (June 2014).” The bale composition from

this demonstration experiment was determined by manual sorting, etc. of plastic containers and packaging

waste selectively discarded from households between April 2012 to March 2013 in Isesaki City, Gunma

Prefecture. As mentioned above, since bale composition ratios vary among municipalities, it must be noted

that the data used here do not necessarily constitute the average bale composition data for plastic containers

and packaging.

Table 4-1. Bale composition ratio used as basis in computations

PE PP PS PET PVC Others Moisture Total

25.0% 27.8% 20.4% 14.8% 0.9% 3.7% 7.3% 100.0% Note: We assumed “others” as metals. Since there was no data on moisture content, we used the value from the 2007 JCPRA Report.

Composition ratio for recycled products and residues for the different processing methods indicated

hereinafter are based on the above bale composition.


Polyolefin ratio (PO%) of recycled products was set to approximately 90% based on the 2007 JCPRA

Report. Likewise, recycling rate was also set to 51% (recycled products total – moisture content), and

product moisture content was set to 0.88% (1.7% if recycled product is set to 100%). (As a result, including

moisture content, total recycled ratio is 51.9%.)

Table 4-2. Composition ratio of recycled products and residues from mechanical recycling (base case)


Recycled

product 21.7% 24.1% 5.2% 0.0% 0.0% 0.0% 0.9% 51.9%

Residues 3.3% 3.7% 15.2% 14.8% 0.9% 3.7% 6.4% 48.1%

Total 25.0% 27.8% 20.4% 14.8% 0.9% 3.7% 7.3% 100.0%

25

Feedstock recycling


For liquefaction and gasification, plastic containers and packaging are directly inputted to the system

after removing metals and other incombustible waste, etc., as such, the following composition ratios were

used.

Table 4-3. Composition ratios set for liquefaction and gasification


25.0% 27.8% 20.4% 14.8% 0.9% 3.7% 7.3% 100.0%


For blast furnace reduction, we used the recycling rate of 75.3%, as indicated in the 2007 JCPRA Report

for April to February of fiscal year 2006. In this report, we set the same removal ratio for PE, PP, PS, and

PET, after removal of PVC and others.

Table 4-4. Composition ratio of recycled products and residues from blast furnace reduction (base case)


Recycled

product 21.4% 23.8% 17.4% 12.7% 0.0% 0.0% 2.0% 77.3%

Residue 3.6% 4.0% 3.0% 2.2% 0.93% 3.7% 5.3% 22.7%

Total 25.0% 27.8% 20.4% 14.8% 0.93% 3.7% 7.3% 100.0%

Note: The recycled product yield excludes moisture content.


For coke-oven chemical material, although the 2007 JCPRA Report for April to February of fiscal year

2006 indicated a recycling rate of 89.5%, we used 89%, since it is the highest recycling rate for the bale

composition in this study.

Table 4-5. Composition ratio of recycled products and residues from coke-oven chemical material (base

case)


Recycled

product 25.0% 27.8% 20.4% 14.8% 0.93% 0.0% 2.0% 91.0%

Residue 0.0% 0.0% 0.0% 0.0% 0.0% 3.7% 5.3% 9.0%

Total 25.0% 27.8% 20.4% 14.8% 0.93% 3.7% 7.3% 100.0%

Note: The recycled product yield excludes moisture content.

26

Energy recovery

RPF use and cement calcination

For RPF use and cement calcination, we conducted calculations based on two yield cases; namely, 75%

yield (same composition ratio as blast furnace reduction) and 89% yield (same as coke-oven chemical

material), following the 2007 JCPRA Report, which indicated blast furnace reduction yield at 75% and

coke-oven chemical material yield at 89%.

Table 4-6. Composition ratio of recycled products and residues from RPF use and cement calcination (75%

yield case)


Recycled

product 21.4% 23.8% 17.4% 12.7% 0.0% 0.0% 2.0% 77.3%

Residue 3.6% 4.0% 3.0% 2.2% 0.93% 3.7% 5.3% 22.7%

Total 25.0% 27.8% 20.4% 14.8% 0.93% 3.7% 7.3% 100.0%

Table 4-7. Composition ratio of recycled products and residues from RPF use and cement calcination (89%

yield case)


Recycled

product 25.0% 27.8% 20.4% 14.8% 0.93% 0.0% 2.0% 91.0%

Residue 0.0% 0.0% 0.0% 0.0% 0.0% 3.7% 5.3% 9.0%

Total 25.0% 27.8% 20.4% 14.8% 0.93% 3.7% 7.3% 100.0%

Incineration with power generation.

For incineration with power generation, we assumed that plastic containers and packagings are subjected

to direct combustion.

Table 4-8. Composition ratios set for incineration with power generation


25.0% 27.8% 20.4% 14.8% 0.9% 3.7% 7.3% 100.0%

27

4.2 CO2 emissions settings

On the basis of the composition ratio set for each method, we computed CO2 emissions upon combustion

of the entire bale and upon combustion of the residues. The C content and CO2 emissions for each type of

material are as shown below.

Table 4-9. CO2 emissions computed from the C content of each plastic material Chemical formula Molecular weight C content CO2 emission

(kg-CO2/kg) PE C2H4 28 24 3.143 PP C3H6 42 36 3.143 PS C8H8 104 96 3.385 PET C10H8O4 192 120 2.292 PVC C2H3Cl 63 24 1.408

CO2 emissions upon combustion of bale

Direct combustion

CO2 emissions upon direct combustion of the bale were computed based on Table 4-1 and Table 4-9 and

are as shown below.

Table 4-10. CO2 emissions upon direct combustion of bale

Bale composition

ratio (%) LHV

(kJ/kg)

Weighted average LHV

(kJ/kg)

CO2 emissions (kg-CO2/kg)

Weighted average CO2 emissions (kg-CO2/kg)

PE 25.0% 46,046 11.530 3.1429 0.787 PP 27.8% 43,953 12.229 3.1429 0.874 PS 20.4% 40,186 8.199 3.3846 0.691 PET 14.8% 23,023 3.416 2.2917 0.340 PVC 0.93% 24,070 0.223 1.4080 0.013 Others 3.7% 0.000 0.000 Moisture 7.3% -2,512 -0.182 0.000 Total 100.0% 35.598 2.705

Note: The bale energy resource consumption data used excluded moisture.

RPF use and cement calcination

CO2 emissions for RPF use and cement calcination were computed as the same as with blast furnace

reducing agent particles for the 75% yield case, and the same as with coke-oven chemical material particles

for the 89% yield case.

28

Table 4-11. CO2 emissions upon combustion of RPF and cement raw fuel (75% yield case)

Bale composition

ratio (%)

LHV

(kJ/kg)


(kJ/kg)

CO2 emissions

(kg-CO2/kg)

Weighted average CO2 emissions

(kg-CO2/kg)

PE 27.7% 46,046 12.748 3.1429 0.870

PP 30.8% 43,953 13.521 3.1429 0.967

PS 22.6% 40,186 9.065 3.3846 0.764

PET 16.4% 23,023 3.777 2.2917 0.376

PVC 0.0% 24,070 0.000 1.4080 0.000

Others 0.0% 0.000 0.000

Moisture 2.6% -2,512 -0.065 0.000

Total 100.0% 39.112 2.976 Note: The RPF/cement raw fuel energy resource consumption data used excluded moisture.

Table 4-12. CO2 emissions upon combustion of RPF and cement raw fuel (89% yield case)

Bale composition

ratio (%)

LHV

(kJ/kg)


(kJ/kg)

CO2 emissions

(kg-CO2/kg)


(kg-CO2/kg)

PE 27.5% 46,046 12.666 3.1429 0.865

PP 30.6% 43,953 13.434 3.1429 0.961

PS 22.4% 40,186 9.007 3.3846 0.759

PET 16.3% 23,023 3.753 2.2917 0.374

PVC 1.02% 24,070 0.245 1.4080 0.014

Others 0.0% 0.000 0.000

Moisture 2.2% -2,512 -0.055 0.000

Total 100.0% 39.105 2.972 Note: The RPF/cement raw fuel energy resource consumption data used excluded moisture.

29

CO2 emissions upon processing of residues

CO2 emissions from mechanical recycling

As shown in Section 5.1.1, mechanical recycling residues were assumed to be processed through energy

recovery (incineration with power generation, RPF use, and cement calcination). Results of computation of

CO2 emissions from the processing of residues for each method are as shown below.

① Incineration with power generation

For incineration with power generation, metal residues were assumed to be directly disposed in landfills,

and residues other than metals subjected to incineration with power generation.

Table 4-13. Processing method for each residue (mechanical recycling) material


Residue 3.3% 3.7% 15.2% 14.8% 0.93% 3.7% 6.4% 48.1%

Combustion 3.3% 3.7% 15.2% 14.8% 0.93% 0.0% 6.1% 44.1% Direct landfilling 0.0% 0.0% 0.0% 0.0% 0.0% 3.7% 0.30% 4.0%

The following are the results of computing CO2 emissions for 1 kg of residue subjected to incineration

with power generation, with 100% as the total of materials (including moisture) to be subjected to

incineration with power generation.

Table 4-14. CO2 emissions upon subjecting residues (mechanical recycling) to incineration with power

generation

Residue

composition ratio (%)

LHV (kJ/kg)


(kJ/kg)



PE 7.5% 4.60E+04 3.47E+00 3.14E+00 2.37E-01 PP 8.4% 4.40E+04 3.68E+00 3.14E+00 2.63E-01 PS 34.6% 4.02E+04 1.39E+01 3.38E+00 1.17E+00 PET 33.6% 2.30E+04 7.75E+00 2.29E+00 7.71E-01 PVC 2.1% 2.41E+04 5.06E-01 1.41E+00 2.96E-02 Others 0.0% 0.00E+00 0.00E+00 Moisture 13.8% -2.51E+03 -3.46E-01 Total 100.0% 2.93E+01 2.47E+00

Note: 1. Residue composition ratio after excluding metals at 3.7% (and further excluding 0.3% bound moisture based on data from PWMI) was set to 100% (including moisture).

2. The residue energy resource consumption data used excluded moisture. ② RPF use and cement calcination

Metals and PVC in residues were excluded since it was assumed that they could not be used as RPF and

as raw fuel for cement calcination. PVC was assumed to be subjected to direct combustion while metals to

be directly disposed in landfills.

30

Table 4-15. Processing ratio for each material in residue (mechanical recycling) from RPF use and cement

calcination


Residue 3.3% 3.7% 15.2% 14.8% 0.93% 3.7% 6.4% 48.1% RPF/cement

raw material

3.3% 3.7% 15.2% 14.8% 0.0% 0.0% 5.6% 42.7%

Selective residue combustion

0.0% 0.0% 0.0% 0.0% 0.93% 0.0% 0.50% 1.4%

Direct landfilling 0.0% 0.0% 0.0% 0.0% 0.0% 3.7% 0.30% 4.0%

Accordingly, results of computation of CO2 emissions during combustion of RPF and cement raw fuel

manufactured from residues are as shown below.

Table 4-16. CO2 emissions upon combustion of residues (RPF/cement raw fuel) Residue


LHV (kJ/kg)


(kJ/kg)



PE 7.8% 4.60E+04 3.59E+00 3.14E+00 2.45E-01 PP 8.7% 4.40E+04 3.81E+00 3.14E+00 2.72E-01 PS 35.7% 4.02E+04 1.44E+01 3.38E+00 1.21E+00 PET 34.8% 2.30E+04 8.00E+00 2.29E+00 7.97E-01 PVC 0.0% 2.41E+04 0.00E+00 1.41E+00 0.00E+00 Others 0.0% 0.00E+00 0.00E+00 Moisture 13.1% -2.51E+03 -3.28E-01 Total 100.0% 2.98E+01 2.52E+00

Note: The RPF/cement raw fuel energy resource consumption data used excluded moisture.

Feedstock recycling

① CO2 emissions from liquefaction

For liquefaction, it was assumed that residues (all part of metals) were disposed in landfills.

② CO2 emissions from gasification

For gasification, it was assumed that residues (all part of metals) were disposed in landfills.

③ CO2 emissions from blast furnace reduction

As shown in Section 5.2.4, blast furnace reduction residues were assumed to be processed through

energy recovery (incineration with power generation, RPF use, and cement calcination). Results of

computation of CO2 emissions from the processing of residues for each method are as shown below.

31

i. Incineration with power generation

For incineration with power generation, metal residues were assumed to be directly disposed in landfills,

and residues other than metals to be subjected to incineration with power generation.

Table 4-17. Processing method for each residue (blast furnace reduction) material


Residue 3.6% 4.0% 3.0% 2.2% 0.93% 3.7% 5.3% 22.7%

Combustion 3.6% 4.0% 3.0% 2.2% 0.93% 0.0% 1.6% 15.3%

Direct

landfilling 0.0% 0.0% 0.0% 0.0% 0.0% 3.7% 0.30% 4.0%

The following are the results of computing CO2 emissions for 1 kg of residue subjected to incineration

with power generation, with 100% as the total of materials (including moisture) to be subjected to


Table 4-18. CO2 emissions upon subjecting residues to incineration with power generation

Residue composition

ratio (%)

LHV (kJ/kg)


(kJ/kg)



PE 23.7% 4.60E+04 1.09E+01 3.14E+00 7.46E-01 PP 26.4% 4.40E+04 1.16E+01 3.14E+00 8.29E-01 PS 19.3% 4.02E+04 7.77E+00 3.38E+00 6.55E-01 PET 14.1% 2.30E+04 3.24E+00 2.29E+00 3.22E-01 PVC 6.0% 2.41E+04 1.46E+00 1.41E+00 8.52E-02 Others 0.0% 0.00E+00 0.00E+00 Moisture 10.4% -2.51E+03 -2.62E-01 Total 100.0% 3.50E+01 2.64E+00

Note: 1. Residue composition ratio after excluding metals at 3.7% (and further excluding 0.3% bound moisture based on data from PWMI) was set to 100% (including moisture).

2. The residue energy resource consumption data used excluded moisture.

32

ii. RPF use and cement calcination

Metals and PVC in residues were excluded since it was assumed that they could not be used as RPF and

as raw fuel for cement calcination. PVC was assumed to be subjected to direct combustion while metals to

be directly disposed in landfills.

Table 4-19. Processing method for each material in residues (blast furnace reduction) from RPF use and

cement calcination


Residue 3.6% 4.0% 3.0% 2.2% 0.9% 3.7% 5.3% 22.7% RPF/cement

raw material

3.6% 4.0% 3.0% 2.2% 0.0% 0.0% 4.5% 17.3%

Selective residue combustion

0.0% 0.0% 0.0% 0.0% 0.9% 0.0% 0.50% 1.4%

Direct landfilling 0.0% 0.0% 0.0% 0.0% 0.0% 3.7% 0.30% 4.0%

Accordingly, results of computation of CO2 emissions upon combustion of RPF and cement raw fuel

manufactured from residues are as shown below.

Table 4-20. CO2 emissions upon combustion of residues (RPF/cement raw fuel) Residue


LHV (kJ/kg)


(kJ/kg)



PE 21.1% 4.60E+04 9.71E+00 3.14E+00 6.63E-01 PP 23.4% 4.40E+04 1.03E+01 3.14E+00 7.36E-01 PS 17.2% 4.02E+04 6.90E+00 3.38E+00 5.81E-01 PET 12.5% 2.30E+04 2.88E+00 2.29E+00 2.86E-01 PVC 0.0% 2.41E+04 0.00E+00 1.41E+00 0.00E+00 Others 0.0% 0.00E+00 0.00E+00 Moisture 25.8% -2.51E+03 -6.49E-01 Total 100.0% 2.98E+01 2.27E+00

Note: The RPF/cement raw fuel energy resource consumption data used excluded moisture.

iii. CO2 emissions from coke-oven chemical material

In regard to CO2 emissions for residues from coke-oven chemical material, since residues are only

metals, they were assumed to be directly disposed in landfills.

33

Combustion of other plastics

Results of computing CO2 emissions for recycled products are as shown below.

Incineration of pallets and other products

It was assumed that after use of recycled products from mechanical recycling, namely, pallets and

compounds manufactured from plastic containers and packaging, they are directly incinerated. Results of

computation of CO2 emissions for such case are as shown below.

Table 4-21. CO2 emissions from incineration of pallets, etc.

Bale


LHV (kJ/kg)


(kJ/kg)



PE 42.6% 46,046 19.604 3.1429 1.338

PP 47.3% 43,953 20.792 3.1429 1.487

PS 10.1% 40,186 4.066 3.3846 0.342

PET 0.0% 23,023 0.000 2.2917 0.000

PVC 0.0% 24,070 0.000 1.4080 0.000

Others 0.0% 0.000 0.000

Moisture 0.0% -2,512 0.000 0.000

Total 100.0% 44.463 3.167


Since inputted bale is subjected to direct combustion for liquefaction and gasification, results were the

same as with Table 4-10.

Table 4-22. CO2 emissions from combustion, etc. for liquefaction and gasification

Bale


LHV (kJ/kg)


(kJ/kg)



PE 25.0% 46,046 11.530 3.1429 0.787

PP 27.8% 43,953 12.229 3.1429 0.874

PS 20.4% 40,186 8.199 3.3846 0.691

PET 14.8% 23,023 3.416 2.2917 0.340

PVC 0.9% 24,070 0.223 1.4080 0.013

Others 3.7% 0.000 0.000

Moisture 7.3% -2,512 -0.182 0.000

Total 100.0% 35.598 2.705 Note: The liquefaction and gasification energy resource consumption data used excluded moisture.

34


Results of computation of CO2 emissions from combustion of blast furnace reducing agent particles

inputted for blast furnace reduction are as shown below.

Table 4-23. CO2 emissions from combustion, etc. of blast furnace reducing agent particles

Bale composition

ratio (%)

LHV

(kJ/kg)


(kJ/kg)

CO2 emissions

(kg-CO2/kg)


(kg-CO2/kg)

PE 27.7% 46,046 12.748 3.1429 0.870

PP 30.8% 43,953 13.521 3.1429 0.967

PS 22.6% 40,186 9.065 3.3846 0.764

PET 16.4% 23,023 3.777 2.2917 0.376

PVC 0.0% 24,070 0.000 1.4080 0.000

Others 0.0% 0.000 0.000

Moisture 2.6% -2,512 -0.065 0.000

Total 100.0% 39.112 2.976 Note: The energy resource consumption data used for blast furnace reducing agent particle combustion excluded moisture.


Results of computation of CO2 emissions from combustion of chemical material inputted for coke-oven

chemical material are as shown below.

Table 4-24. CO2 emissions from combustion, etc. of chemical material particles

Bale composition

ratio

(%)

LHV

(kJ/kg)


(kJ/kg)

CO2 emissions

(kg-CO2/kg)


(kg-CO2/kg)

PE 27.5% 46,046 12.666 3.1429 0.865

PP 30.6% 43,953 13.434 3.1429 0.961

PS 22.4% 40,186 9.007 3.3846 0.759

PET 16.3% 23,023 3.753 2.2917 0.374

PVC 1.0% 24,070 0.245 1.4080 0.014

Others 0.0% 0.000 0.000

Moisture 2.2% -2,512 -0.055 0.000

Total 100.0% 39.105 2.972 Note: The energy resource consumption data used for chemical material particle combustion excluded moisture.

35

4.3 Setting of assumptions and conditions for evaluation

The following are the assumptions and conditions for evaluation.

(Processing of residues)

・ In the processing of residues in the recycling system, those for mechanical recycling and for

feedstock recycling through blast furnace reduction reflected the recycling status for fiscal year 2017.

Processing of residues was done through simple incineration, incineration with power generation,

RPF use, and cement calcination. The actual situation was reflected by obtaining the weighted

average, in consideration of the ratio of each processing method. The power generation efficiency of

incineration with power generation was based on the current average efficiency for waste-to-energy

power generation of 12.81%.

(Handling of by-products)

・ By-products (slag, hydrochloric acid, distillation residues, carbonic acid, etc.) were included as

targets of evaluation (Excess hydrogen generated during ammonia production, however, was

disregarded.)

(Use of practical units for functional units)

・ We adjusted the practical units for functional units (e.g. number of pieces for pallets) to enable

evaluation of equivalent raw materials or fuels; except for compounds, which are intermediate

products that are clearly not equivalent to new resin, wherein we used substitution ratio in reference

to the case for pallets.

(Bale processing in the targets for comparison)

・ In regard to the original system used in the comparison, as shown in the figures explaining the

system boundaries and functional units, simple incineration was the method assumed for waste

processing of bale from plastic containers and packaging.

(Handling of transport operations)

・ Transport operations within recycling facilities and facilities of operators using the recycled products

were included in the product manufacturing process. Since the transport operations to recyclers, to

operators using) the recycled products, and to entities actually using the final products are

completely different for each operator, they were not included in this study, as with other previous

studies. Transport of residues and other waste materials was assumed to be for a distance of 30 km,

using a 4-ton truck, and for one-way transport.

(Background data)

・ The analysis of inventory data obtained from different sources required the standardization of data

used for fuel, resources, etc. For this study, we used IDEA Ver. 2.2 developed by the National

Institute of Advanced Industrial Science and Technology.

36

Inventory data for each processing method

5.1 Mechanical recycling


Since residues from mechanical recycling are subjected to energy recovery processing, we computed the

environmental burden for each residue processing method.

RPF use

The following table shows the inventory data for manufacturing RPF from residues.

Table 5-1. Inventory data for production of RPF from 1 kg of residue

The inventory data for incineration and use/ residue landfilling of RPF based on Table 4-11 are as shown

below.

Table 5-2. Inventory data for incineration and use/ residue landfilling for 0.89 kg of RPF

The inventory data for selected PVC, which is subjected to simple incineration and residue landfilling,

are as shown below.

Table 5-3. Inventory data for simple incineration/ residue landfilling for 0.02 kg of sorted residues

Input/output item Active mass Energy resource consumption (MJ)

CO2 emission(kg-CO2)

Input Raw material RPF raw material 1.00E+00 kgUtility Power 1.30E-01 kWh 1.24E+00 7.52E-02

Output Generated product RPF 8.87E-01 kg

Others Sorted residues 1.93E-02 kgTotal 1.24E+00 7.52E-02



Input Raw material RPF incineration 8.87E-01 kg 2.64E+01 2.24E+00

Output Generated product Residue (landfilling) 2.75E-02 kg 1.63E-02 9.88E-04

Total 2.64E+01 2.24E+00



Input Raw material Sorted residues 1.93E-02 kg 4.64E-01 2.71E-02Utility Power 3.86E-04 kWh 3.69E-03 2.24E-04Utility LPG 5.94E-05 MJ 6.85E-05 4.50E-06Utility B-class heavy oil 7.99E-05 MJ 8.82E-05 6.62E-06


Total 4.68E-01 2.74E-02

37

Since manufactured RPF is usually used in solid fuel boilers, such as coal-fired boilers and RPF

single-fuel fired boilers used by paper manufacturers, etc., it was considered as a substitute for coal.

In this case, weight of substituted coal for 1 kg of RPF was computed by taking into account an 88%

boiler efficiency for RPF combustion (data from PWMI) and a 90% boiler efficiency for coal combustion

(data from PWMI), and adjusting calorific value:

Coal = 29,752 kJ/kg (RPF) ×0.88 ÷ 0.9 ÷ (26,600 kJ/kg (Coal) × 0.975) ＝ 1.12 kg Note: Net heating value (lower heating value) = Gross heating value (higher heating value) × 0.975

The inventory data for combustion of coal substituting 0.89 kg of RPF are as shown below.

Table 5-4. Inventory data for simple incineration / residue landfilling for 1.0 kg of coal

Accordingly, the environmental load for RPF use of residues is the value obtained by deducting the

environmental load for coal combustion from the environmental load in manufacturing and using RPF.

Table 5-5. Environmental load for RPF use of residues in mechanical recycling

Cement calcination

The inventory data for manufacture of cement raw fuel from residues are as shown below.

Table 5-6. Inventory data for manufacturing cement raw fuel from 1 kg of residues



Output Generated product Coal (combustion) 9.95E-01 kg 2.69E+01 2.47E+00

Total 2.69E+01 2.47E+00

Process Energy resource consumption (MJ)


RPF production 1.24E+00 7.52E-02RPF incineration and use/ residue landfilling 2.64E+01 2.24E+00Simple incineration/residue landfilling of sorted residues 4.68E-01 2.74E-02Combustion of coal (RPF substitution effect) -2.69E+01 -2.47E+00Total 1.31E+00 -1.18E-01



Input Raw material Input material 1.00E+00 kgUtility Power 1.57E-01 kWh 1.50E+00 9.10E-02Utility Light oil component 3.80E-02 MJ 4.13E-02 2.98E-03

Output Generated product Cement raw fuel 8.87E-01 kg


38

The inventory data for incineration and use / residue landfilling of cement raw material based on Table

4-11 are as shown below.

Table 5-7. Inventory data for incineration and use / residue landfilling of 0.89 kg of cement raw material

The following inventory data for selected PVC, which is subjected to simple incineration and residue

landfilling, are as shown below.


Assuming that 1 kg of manufactured cement raw fuel is substituted by coal, the amount of coal to

substitute 1 kg of cement raw fuel is computed as follows:

・Coal ＝ 29,752 kJ/kg (cement raw fuel) ÷ (26,600 kJ/kg (coal) × 0.975) ＝1.15 kg Note: Net heating value (lower heating value) = Gross heating value (higher heating value) × 0.975

The inventory data for combustion of coal substituting 0.89 kg of cement raw fuel are as shown below.




Input Raw material Cement raw fuel incineration 8.87E-01 kg 2.64E+01 2.24E+00


Total 2.64E+01 2.24E+00





Total 4.68E-01 2.74E-02



Output Generated product Coal (combustion) 1.02E+00 kg 2.75E+01 2.52E+00

Total 2.75E+01 2.52E+00

39

Accordingly, the environmental load for cement calcination of residues is the value obtained by

deducting the environmental load for coal combustion from the environmental load for manufacturing and

using cement raw fuel.

Table 5-10. Environmental load for cement calcination of residues in mechanical recycling


The inventory data for incineration with power generation of residues at 12.81% efficiency are as shown

below. Power generation from 1 kg of residues was computed as follows based on the power generation

efficiency and the unit calorific value from Table 4-14:

Power generation ＝ 29.3 MJ/kg (residue calorific value) ÷ 3.6 MJ/kWh (power conversion) × 12.81%

(power generation efficiency) ＝ 1.04 kWh/kg

Table 5-11. Inventory data for incineration with power generation for 1 kg of residues

It was assumed that the generated power is substituted by the grid power, which was computed by

subtracting the power used within the plant from the generated power:

Grid power ＝ Power generation － Power used within the plant ＝ 1.04 kWh – 0.0126 kWh＝ 1.03

kWh

The inventory data for grid power substituting 1.04 kWh of generated power are as shown below.



Cement raw fuel production 1.54E+00 9.40E-02Cement raw fuel incineration and use/residue landfilling 2.64E+01 2.24E+00Simple incineration/residue landfilling of sorted residues 4.68E-01 2.74E-02Combustion of coal (cement raw fuel substitution effect) -2.75E+01 -2.52E+00Total 9.98E-01 -1.55E-01



Input Raw material Residue incineration 1.00E+00 kg 2.93E+01 2.47E+00Utility Power (internal use) 1.26E-02 kWh 0.00E+00 0.00E+00Utility Utility gas 1.58E-02 MJ 2.26E-02 9.89E-04Utility A-class heavy oil 2.72E-03 MJ 3.07E-03 2.20E-04

Output Generated product Power generation 1.04E+00 kWh

Others Residue (landfilling) 3.10E-02 kg 1.84E-02 1.13E-03Total 2.95E+01 2.48E+00

40

Table 5-12. Inventory data for 1.0 kWh of grid power

Accordingly, the environmental load for incineration with power generation of residues is the value

obtained by deducting the environmental load for grid power from the environmental load for incineration

with power generation.

Table 5-13. Environmental load for incineration with power generation of residues in mechanical recycling

Environmental load of residues

From the results in (1) to (3) above, the environmental load related to the processing of residues was

calculated by taking into account the environmental load of each method computed by allocating 0.48 kg of

residues according to the residue composition ratio shown in Table 3-1 and the reduction in environmental

load achieved by substitution (power, coal), and by combining the environmental load of direct landfilling

of metals.

Table 5-14. Environmental load for processing of 0.48 kg of residues through mechanical recycling



Output Generated product Grid power 1.03E+00 kWh 9.86E+00 5.97E-01

Total 9.86E+00 5.97E-01



Incineration with power generation, residue landfilling 2.95E+01 2.48E+00Grid power (incineration with power generation substitution effect) -9.86E+00 -5.97E-01

Total 1.96E+01 1.88E+00



Environmental load

RPF use 6.62E+00 5.51E-01Cement calcination 3.20E+00 2.66E-01Incineration with power generation 2.78E+00 2.35E-01Direct landfilling 5.62E-04 1.46E-03

Substitution effect

Combustion of coal (RPF substitution effect) -6.32E+00 -5.79E-01Combustion of coal (cement raw fuel substitution effect) -3.09E+00 -2.83E-01

Grid power (incineration with power generation substitution effect) -9.32E-01 -5.64E-02

Total 2.27E+00 1.35E-01

41

Returnable pallet (substitute for new resin)

The system boundary for returnable pallet (substitute for new resin) is shown below.

Figure 5-1. System boundary for returnable pallet (substitute for new resin)

Weight and substitution ratio of returnable pallet

The weight, substitution ratio, etc. of returnable pallet used in the 2007 JCPRA Report have been revised

in the “FY2016 Update of inventory data for environmental load reduction effect of recycling of plastic

containers and packaging” (JCPRA, January 2017; hereinafter, “2017 JPCRA Report”). In this study, we set

the weight and substitution ratio of returnable pallet based on the 2017 JPCRA Report.

We also defined substitution ratio as the ratio of the weight of pallet manufactured using 100% new resin

against the weight of pallet manufactured using 100% plastic containers and packaging.

Confirmation of pallet quality (size, load capacity)

The 2017 JCPRA Report implemented revisions based on data for 31 types of pallet sold by different

business entities. The report determined whether the quality (size, load capacity) of these pallets was

comparable.

Results of studies conducted with the cooperation of JCPRA showed that for the 17 cases in Table 5-15,

quality was equal and comparable at a size of 1100 mm × 1100 mm and load capacity of 1000 kg.

Substitution ratio was estimated based on these 17 cases.

Recycling system


Original system

Materials(resin)


Pallet(0.0217pcs.)

9.5 kg/pc.


0.21 kg

Creation of product

(molding, etc.)

MaterialsProduction

PE+PP＝0.21 kg

Bale input Sorting


Shredding, gravity sorting

Creation of product

(molding, etc.)

Pallet(0.0217pcs.)23.5 kg/pc.


1 kg0.51 kg 0.51 kg


Plastic containers

and packaging

1 kg

Recycled product


transport

Plastic containers

and packaging

1 kg

0.48 kg

Incineration with power generationRPF use

Cement calcination

* Practical unit standardized based on number of pallets (C pcs.)(Here, 0.0217 pieces.)

42

Table 5-15. Material, weight, and quality of plastic pallets

Estimate of substitution ratio in plastic pallets

Since all the pallets for the 17 cases had a load capacity of 1000 kg and size of 1100 mm × 1100 mm,

they were considered as equivalent.

Group A pallets had a plastic containers and packaging ratio of 35% to 51% and included recycled PP or

new resin PP, other than the plastic containers and packaging. We believe that it is also possible to

manufacture pallets with a load capacity of 1000 kg at around the same product weight and size by using

100% new resin. Group B and C pallets, on the other hand, are pallets manufactured using almost 100%

plastic containers and packaging.

On the basis of the above assumptions and pallet data for the 17 cases, we estimated the substitution rate

using the following formula.

Substitution ratio = (Weight of pallet manufactured using 100% new resin) / (Weight of pallet

manufactured using 100% plastic containers and packaging)

The (weight of pallet manufactured using 100% new resin) is believed to be equal or less than the weight

of Group A pallets. Assuming that the weight is equal to weight of Group A pallets, we calculated the

simple average, minimum value, and maximum value of the (weight of pallet manufactured using 100%

new resin) as shown below.

Simple average: 9.5 kg

Minimum value: 7.5 kg

Maximum value: 7.5 kg

Likewise, assuming that the (weight of pallet manufactured using 100% plastic containers and

packaging) is equal to the weight of Group B and Group C pallets, we calculated the simple average,

43

minimum value, and maximum value of the (weight of pallet manufactured using 100% plastic containers

and packaging) as shown below.

Simple average: 23.5 kg

Minimum value: 18 kg

Maximum value: 33 kg

The following table shows the results of calculating the substitution ratio based on the above results. We

also calculated the substitution ratios in the 2007 JCPRA Report.

Table 5-16. Substitution ratio for each case

* Since the (weight of pallet manufactured using 100% new resin) was assumed to be equal to the weight of Group A pallets,

the estimates were higher.

The following sections show results of calculation of environmental load reduction for the three cases;

namely, simple average, minimum value, and maximum value.

(1) Weight of pallet manufactured using 100% new resin

(2) Weight of pallet manufactured using 100% plastic containers and packaging

(3) Substitution ratio(3)＝(1)÷(2)

2017 JCPRA Report

7.5 kg/pc. 20 kg/pc. 0.375

Minimum value

7.5 kg/pc. 33 kg/pc. 0.227

Simple average

9.5 kg/pc. 23.5 kg/pc. 0.404

Maximum value

10.3 kg/pc. 18 kg/pc. 0.572

44

Returnable pallet (substitute for new resin, substitution ratio for simple average case)

Inventory data for recycling system

The inventory data for collection, transport, and baling of plastic containers and packaging are as shown

below.

Table 5-17. Inventory data for collection, transport, and baling of 1 kg of plastic containers and packaging

The inventory data for the process of manufacturing pellet from bale are as shown below.

Table 5-18. Inventory data for pelleting of 1 kg of bale

The inventory data for the process of manufacturing pallet from pellet are as shown below. Due to small

input amounts for non-slip rubber, waste toner, pigments, modifying materials, and used grease, they were

excluded from the calculation.



Input Raw material Plastic containers and packaging

1.00E+00 kg

Output Utility Collection and transport 1.00E+00 kg 5.98E-01 4.07E-02

Utility Baling 1.00E+00 kg 5.58E-01 2.17E-02Utility Transport 1.00E+00 kg 1.09E-01 7.33E-03

Total 1.26E+00 6.97E-02



Input Raw material Bale 1.00E+00 kgUtility Power 4.19E-01 kWh 4.01E+00 2.43E-01

Light oil component 4.18E-01 MJ 4.55E-01 3.28E-02COG 3.55E-01 MJ 0.00E+00 1.43E-02Water 1.55E-03 m3 3.60E-03 2.20E-04

Output Generated product Pellet 5.10E-01 kg

Others Residue processing（ER） 4.80E-01 kg 2.27E+00 1.35E-01

Total 6.74E+00 4.25E-01

45

Table 5-19. Inventory data for pelleting of 0.51 kg of pellet

It was assumed that after their use, pallets manufactured from plastic containers and packaging are

processed through simple incineration and landfilling. The inventory data for these processes are shown as

shown below.

Table 5-20. Inventory data for simple incineration and landfilling of 0.51 kg of pallet

Inventory data for original system

For the original system, plastic containers and packaging are assumed to be subjected to simple

incineration after collection, transport, and baling. The inventory data for collection, transport, and baling

of 1 kg of plastic containers and packaging are the same as that shown in Table 5-17.

Next, the inventory data for simple incineration and residue landfilling of bale are as shown below.

Table 5-21. Inventory data for simple incineration and landfilling of 1 kg of bale



Input Raw material Pellet 5.10E-01 kgOthers Non-slip ruber 4.41E-03 kg ExcludedOthers Waste toner 2.23E-03 kg ExcludedOthers Pigments 6.54E-04 kg ExcludedOthers Modifying materials 6.54E-04 kg ExcludedUtility Power 3.19E-01 kWh 3.05E+00 1.85E-01Utility Light oil component 1.61E-02 MJ 1.74E-02 1.26E-03Utility Used grease 3.41E-06 kg ExcludedUtility Industrial water 1.81E-04 m3 4.21E-04 2.57E-05

Output Generated product Pallet（23.5 kg/pc.） 5.10E-01 kg

Total 3.07E+00 1.86E-01



Input Raw material Pallet incineration 5.10E-01 kg 2.27E+01 1.62E+00Utility Power 6.63E-03 kWh 6.35E-02 3.84E-03Utility LPG 1.02E-03 MJ 1.18E-03 7.74E-05Utility B-class heavy oil 1.37E-03 MJ 1.52E-03 1.14E-04


Total 2.28E+01 1.62E+00



Input Raw material Bale 1.00E+00 kg 3.56E+01 2.71E+00Utility Power 1.30E-02 kWh 1.24E-01 7.54E-03

LPG 2.00E-03 MJ 2.31E-03 1.52E-04B-class heavy oil 2.69E-03 MJ 2.97E-03 2.23E-04

Output Others Residue (landfilling) 3.10E-02 kg 1.84E-02 1.13E-03

Total 3.57E+01 2.71E+00

46

Substitution ratio of pallet made from new resin with pallet made from plastic containers and packaging

was set to 0.404 based on the simple average value in (1). Thus, the weight of pallet made from new resin

equivalent to 0.51 kg of pallet made from plastic containers and packaging is 0.21 kg. The composition of

pallet made from new resin was assumed to be PE : PP ＝ 1：1.

The inventory data for manufacturing 0.21 kg of pallet from new resin are as shown below.

Table 5-22. Inventory data for manufacturing pallet from new resin

It was assumed that after their use, pallets manufactured from new resin are processed through simple

incineration and landfilling. The inventory data for these processes are as shown below.

Table 5-23. Inventory data for simple incineration and landfilling of pallets made from new resin

Returnable pallet (substitute for new resin, substitution ratio for simple average case) summary

Environmental load of recycling system

Table 5-24. Environmental load of recycling system for returnable pallet (substitute for new resin,

substitution ratio for simple average case)



Input Raw material PE 1.03E-01 kg 6.58E+00 1.97E-01Raw material PP 1.03E-01 kg 6.69E+00 2.02E-01Utility Power 1.95E-01 kWh 1.87E+00 1.13E-01


Total 1.51E+01 5.13E-01



Input Raw material Pallet incineration 2.06E-01 kg 9.28E+00 6.48E-01Utility Power 2.68E-03 kWh 2.57E-02 1.55E-03Utility LPG 4.13E-04 MJ 4.76E-04 3.13E-05Utility B-class heavy oil 5.55E-04 MJ 6.13E-04 4.60E-05


Total 9.31E+00 6.50E-01



Collection, transport, and baling 1.26E+00 6.97E-02Pellet production 6.74E+00 4.25E-01Returnable pallet production 3.07E+00 1.86E-01Returnable pallet incineration, landfilling 2.28E+01 1.62E+00Total 3.38E+01 2.30E+00

47

Environmental load of original system

Table 5-25. Environmental load of original system for returnable pallet (substitute for new resin,

substitution ratio for simple average case)

Environmental load reduction effect

Table 5-26. Environmental load reduction effect for returnable pallet (substitute for new resin, substitution

ratio for simple average case)



Collection, transport, and baling 1.26E+00 6.97E-02Bale simple incineration, residue landfilling 3.57E+01 2.71E+00New resin pallet (plastic containers and packaging pallet substitute) production 1.51E+01 5.13E-01

New resin pallet (plastic containers and packaging pallet substitute) incineration, residue landfilling 9.31E+00 6.50E-01

Total 6.15E+01 3.95E+00

Energy resource consumption (MJ)


Environmental load reduction effect (returnable pallet (new resin substitute, simple average substitution ratio)) 2.76E+01 1.65E+00

48

Returnable pallet (substitute for new resin, substitution ratio for minimum value case)


Since the inventory data for the recycling system is independent of the substitution ratio, the data are the

same as with the simple average case in (2).





Next, the inventory data for simple incineration and residue landfilling of bale are the same as that

shown in Table 5-21.


was set to 0.227 based on the minimum value in (1). Thus, the weight of pallet made from new resin







Table 5-28. Inventory data for simple incineration and landfilling of pallets made from new resin





Total 8.51E+00 2.88E-01





Total 5.23E+00 3.65E-01

49

Returnable pallet (substitute for new resin, substitution ratio for minimum value case) summary



substitution ratio for minimum value case)



substitution ratio for minimum value case)



ratio for minimum value case)








Total 5.08E+01 3.44E+00




50

Returnable pallet (substitute for new resin, substitution ratio for maximum value case)


Since the inventory data for the recycling system is independent of the substitution ratio, the data are the

same as with the simple average case in (2).





Next, the inventory data for simple incineration and residue landfilling of bale are the same as that

shown in Table 5-21.


was set to 0.572 based on the maximum value in (1). Thus, the weight of pallet made from new resin







Table 5-33. Inventory data for simple incineration and landfilling of pallet made from new resin





Total 2.14E+01 7.26E-01





Total 1.32E+01 9.20E-01

51

Returnable pallet (substitute for new resin, substitution ratio for maximum value case) summary



substitution ratio for maximum value case)



substitution ratio for maximum value case)



ratio for maximum value case)








Total 7.16E+01 4.43E+00




52

Returnable pallet (substitute for new resin) summary

For returnable pallet (substitute for new resin), we computed environmental load reduction effect by

changing the substitution ratio of new resin against plastic containers and packaging.

Table 5-37. Environmental load reduction effect at different substitution ratios of returnable pallet

(substitute for new resin)

Since the weight of the virgin pallet for substitution increased with the increase in substitution ratio, the

environmental load of the original system increased (no effect to the recycling system). This shows that the

environmental load reduction effect changes depending on the substitution ratio.

The following table shows the environmental load reduction effect when the substitution ratio is set to 1.

Table 5-38. Environmental load reduction effect when the substitution ratio of returnable pallet (substitute

for new resin) is set to 1

This shows that increasing the quality of collected plastic containers and packaging to a level similar to

that of new resin will enable a high environmental load reduction effect from mechanical recycling.


CO2 emission (kg-CO2)

Environmental load reduction effect (minimum substitution ratio) 1.69E+01 1.14E+00

Environmental load reduction effect (simple average substitution ratio) 2.76E+01 1.65E+00

Environmental load reduction effect (maximum substitution ratio) 3.78E+01 2.13E+00



Environmental load reduction effect (substitution ratio =1) 6.37E+01 3.36E+00

53

Returnable pallet (substitute for new wood)

The system boundary for returnable pallet (substitute for new wood) is shown below.

Figure 5-2. System boundary for returnable pallet (substitute for new wood)

Weight and substitution ratio of returnable pallet

The following sections show the weight of returnable pallet manufactured from plastic containers and

packaging and of wood pallet with the same function. The weight of returnable pallet manufactured from

plastic containers and packaging is the same as that of the returnable pallet (substitute for new resin). The

weight of wood pallet with the same function is based on the 2007 JCPRA Report.

Table 5-39. Weight of returnable pallet targeted for evaluation


The inventory data for the recycling system are the same as that of the returnable pallet (substitute for

new resin).


grav ity sortingRecy cled product

Creation of product(molding, etc.)


Recycling system

1 kg

*Practical unit standardized based on number of pallets

Bale input


Original system

1 kg

Logging, import Incineration, landfillingProcessingRaw wood,

lumber



packaging1 kg


1 kg


0.70 kg

0.51 kg


0.48 kg


RPF use

Cement calcination

Pallet(0.022 pcs.)23.5 kg/pc.

0.51 kg

0.65 kg

Pallet(0.022 pcs.)30 kg/pc.

Production volume Unit weight Number of pallets

Returnable pallet (plastic containers and packaging)

0.51 kg 23.5 kg/pc. 0.0217 pcs.

Virgin pallet (new wood)

0.65 kg 30 kg/pc. 0.0217 pcs.

54


The inventory data for collection, transport, and baling of plastic containers and packaging, and for

incineration and landfilling of bale are the same as that of the original system in Section 5.1.2.

For the inventory data for the logging and transport (import) of wood (imported) that serve as material

for wood pallets, we used the inventory data from the 2007 JCPRA Report. The inventory data for each of

the processes of sawing of raw wood, processing pallet from lumber, and incineration and landfilling of

wood pallets are as shown below.

Table 5-40. Inventory data for sawing of raw wood

Table 5-41. Inventory data for processing pallet from lumber

Table 5-42. Inventory data for incineration and landfilling of wood pallets



Input Raw material Raw wood 6.95E-01 kg 3.31E-01 9.73E-02Utility Power 3.52E-02 kWh 3.37E-01 2.04E-02Utility Light oil component 1.06E-03 MJ 1.15E-03 8.32E-05

Utility Waste wood (used within the premises) 4.38E-02 kg

Output Generated product Lumber 6.51E-01 kg

Others Waste wood (used within the premises) 4.38E-02 kg

Total 6.70E-01 1.18E-01



Input Raw material Lumber 6.51E-01 kgUtility Power 4.38E-03 kWh 4.20E-02 2.54E-03Utility Light oil component 1.33E-02 MJ 1.44E-02 1.04E-03

Output Generated product Pallet（30 kg/pc.） 6.51E-01 kg

Total 5.64E-02 3.58E-03



Input Raw material New wood pallet incineration 9.38E+00 MJ 0.00E+00 2.09E-02


Total 1.20E-02 2.16E-02

55

Returnable pallet (substitute for new wood) summary


Table 5-43. Environmental load of recycling system for returnable pallet (substitute for new wood)


Table 5-44. Environmental load of original system for returnable pallet (substitute for new wood)


Table 5-45. Environmental load reduction effect for returnable pallet (substitute for new wood)






Collection, transport, and baling 1.26E+00 6.97E-02Bale simple incineration, residue landfilling 3.57E+01 2.71E+00Raw wood production 6.70E-01 1.18E-01New wood (returnable pallet substitute) production 5.64E-02 3.58E-03New wood (returnable pallet substitute) incineration, residue landfilling 1.20E-02 2.16E-02

Total 3.77E+01 2.93E+00



Environmental load reduction effect (returnable pallet (substitute for new wood) 3.92E+00 6.26E-01

56

Recycled resin (compound)

The system boundary for recycled resin (compound) is shown below.

Figure 5-3. System boundary for recycled resin (compound)

Substitution ratio of new resin with recycled resin

For the substitution ratio of new resin with recycled resin (f), we carried out calculations for two cases;

namely, when substitution ratio is equal to 1 (carry out the same function at the same weight) and when

substitution ratio is equal to 0.5 (carry out the same function with new resin at half the weight of recycled

resin).


The inventory data for collection, transport, and baling of plastic containers and packaging, and for the

process of manufacturing pellet (recycled product) from the bale are the same as that of returnable pallet

(substitute for new resin). The inventory data for the process of manufacturing recycled resin from pellet

and for incineration and landfilling of recycled resin are as shown below.

Table 5-46. Inventory data for manufacturing recycled resin


grav ity sortingRecy cled product Resin production Recy cled resin Incineration,

landfilling

Recycling system

1 kg0.51 kg 0.51 kg


Plastic containers

and packaging

1 kg


Original system

1 kg

Crude oil resource collection Incineration, landfilling

0.51 kg×f

PE/PP (resin)


1 kg


*Practical unit based on substitution with compound (recycled resin) weight and set as substitution ratio.


0.48 kg


RPF use

Cement calcination



Input Raw material Pellet 5.10E-01 kgUtility Power 2.14E-01 kWh 2.04E+00 1.24E-01

Output Generated product Compound 5.10E-01 kg

Total 2.04E+00 1.24E-01

57

Table 5-47. Inventory data for incineration and landfilling of recycled resin


The inventory data for collection, transport, and baling of plastic containers and packaging, and for

incineration and landfilling of bale are the same as that of the original system in Section 5.1.2.

The inventory data for the process of manufacturing new resin (PE/PP) from crude oil resources and for

the incineration and landfilling of new resin are as shown below. The following table shows results when

the substitution ratio was set to 1. The inventory data for a different substitution ratio can be obtained by

multiplying the target substitution ratio with the inventory data shown below. Section (4) also shows results

when substitution ratio was set to 0.5.

Table 5-48. Inventory data for manufacturing new resin (substitution ratio = 1)

Table 5-49. Inventory data for incineration and landfilling of new resin (substitution ratio = 1)

Recycled resin (compound) summary

The following are the results for two cases; namely, when substitution ratio of new resin with recycled

resin was set to 1, and when substitution ratio was set to 0.5. The results follow the flow diagram shown at



Input Raw material Compound 5.10E-01 kg 2.27E+01 1.62E+00Utility Power 6.63E-03 kWh 1.50E-03 3.84E-03Utility LPG 1.02E-03 MJ 2.62E-05 7.74E-05Utility B-class heavy oil 1.37E-03 MJ 3.38E-05 1.14E-04


Total 2.27E+01 1.62E+00



Input Raw material PP 2.55E-01 kg 1.63E+01 4.88E-01Raw material PE 2.55E-01 kg 1.65E+01 5.01E-01

Total 3.28E+01 9.89E-01



Input Raw material PP incineration 2.55E-01 kg 1.12E+01 8.01E-01Raw material PE incineration 2.55E-01 kg 1.17E+01 8.01E-01Utility Power 6.63E-03 kWh 1.50E-03 3.84E-03Utility LPG 2.04E-05 MJ 5.24E-07 1.55E-06Utility B-class heavy oil 3.06E-05 MJ 7.53E-07 2.54E-06


Total 2.30E+01 1.61E+00

58

the beginning of Section 5.1.4, wherein the environmental load of the recycling system was the same

regardless of the substitution ratio, and production volume of new resin was changed depending on

substitution ratio. The inventory data for the process of new resin manufacture, incineration, and residue

landfilling were changed in proportion to the substitution ratio.


Table 5-50. Environmental load of recycling system for recycled resin (compound)


(1) Substitution ratio = 1

Table 5-51. Environmental load of original system for recycled resin (compound)

(substitution ratio = 1)

(2) Substitution ratio = 0.5

Table 5-52. Environmental load of original system for recycled resin (compound)

(substitution ratio = 0.5)



Collection, transport, and baling 1.26E+00 6.97E-02Pellet production 4.47E+00 2.90E-01Compound production 2.04E+00 1.24E-01Compound residue processing 2.27E+01 1.35E-01Recycled resin compound incineration, residue landfilling 2.27E+01 1.62E+00Total 3.27E+01 2.24E+00



Collection, transport, and baling 1.26E+00 6.97E-02Bale simple incineration, residue landfilling 3.57E+01 2.71E+00New resin production 3.28E+01 9.89E-01New resin incineration, residue landfilling 2.30E+01 1.61E+00Total 9.28E+01 5.38E+00



Collection, transport, and baling 1.26E+00 6.97E-02Bale simple incineration, residue landfilling 3.57E+01 2.71E+00New resin production 1.64E+01 4.94E-01New resin incineration, residue landfilling 1.15E+01 8.04E-01Total 6.49E+01 4.08E+00

59


(1) Substitution ratio = 1

Table 5-53. Environmental load reduction effect for recycled resin (compound)

(substitution ratio = 1)

(2) Substitution ratio = 0.5

Table 5-54. Environmental load reduction effect for recycled resin (compound)

(substitution ratio = 0.5)



Reduction effect (recycled resin: substitution ratio = 1) 6.01E+01 3.14E+00



Reduction effect (recycled resin: substitution ratio = 0.5) 3.22E+01 1.84E+00

60

5.2 Feedstock recycling

Liquefaction

The system boundary for liquefaction is shown below.

Figure 5-4. System boundary for liquefaction


The inventory data for the process of collecting, transporting, and baling of plastic containers and

packaging are as shown in Table 5-17.

Also, generated oil is divided into light oil, medium gravity oil, and heavy oil, which correspond to

naphtha, A-class heavy oil, and C-class heavy oil, respectively. The scope of the system was set to include

their use as diesel fuel, boiler fuel, etc. Also, excess and deficiency of hydrochloric acid and distillation

residue co-products were corrected. However, since the amount of CO2 emitted in the final use stage of

these products is the same as the carbon content of the plastic containers and packaging, computations were

made by assuming that all the carbon (C) content of the inputted plastic containers and packaging is

converted to CO2. The inventory data for liquefaction manufacturing from 1 kg of bale are as shown below.

Bale input Sorting

Residue landfilling

Reduction and

solidification

Py rolysis(dechlorination,

thermoly sis, distillation)

Shipping: 0.11 kg→4.5MJ

Recycling system

1 kg

0.0295 kg

Co-product (hydrochloric acids): 0.075 kg



packaging1 kg

Recy cled product (light oil)

Recy cled product (medium gravity oil)

Recy cled product (heavy oil)

Shipping: 0.014kg→0.62MJ


Co-product(distillation residues): 0.18 kg→3.1MJ


Original system

1 kg


Hy drochloric acid production facility 0.075 kg




Hy drochloric acid


1 kg


packaging

4.5 MJ equiv alentRecy cled product equivalent (Naphtha raw material)

0.62 MJ equivalentRecy cled product equivalent

(A-class heavy oil)

7.7 MJ equiv alentRecy cled product equivalent

(C-class heavy oil)






Materials production Coal (Residue substitution) 3.1 MJ equiv alent

*Practical unit standardized based on calorific values for light oil, medium gravity oil, and heavy oilNote: Generated oil: light oil (naphtha), medium gravity oil (A-class heavy oil), and heavy oil (C-class heavy oil)

Captiv e consumption: 0.171 kg

Captiv e consumption: 0.137 kg

61

Table 5-55. Inventory data for liquefaction manufacturing from bale


The inventory data for collection, transport, and baling of plastic containers and packaging for the

original system are as shown in Table 5-17. Moreover, the inventory data for simple incineration and

residue landfilling of bale are as shown in Table 5-21.

Light oil corresponds to naphtha; medium gravity oil to A-class heavy oil; heavy oil to C-class heavy oil;

and distillation residue to coal. The respective equivalent calorific values were then compared to decide the

necessary amounts for naphtha, A-class heavy oil, C-class heavy oil, and coal. Also, hydrochloric acid is

assumed to be equivalent to the amount generated from liquefaction. However, since the data for the IDEA

V.2.2. used in this study was for 35% hydrochloric acid, we decided the amount of hydrochloric acid and

pure water by comparing the weight to make it equivalent to 10% hydrochloric acid. The respective

substitution relationships are as shown below.

Table 5-56. Substitution relationships for liquefaction recycling system and original system



Input Raw material Bale 1.00E+00 kg 3.56E+01 2.71E+00

Utility Light oil component 2.28E-02 MJ 2.48E-02 1.79E-03

Tap water 1.10E-04 m3 6.32E-04 3.87E-05

Water 4.43E-03 m3 1.03E-02 6.30E-04

Output Generated product

Light oil 1.08E-01 kgLight oil (captive consumption) 1.71E-01 kg

Medium gravity oil 1.37E-02 kgHeavy oil 1.68E-01 kgHeavy oil (captive consumption) 1.37E-01 kg

Others Residue (landfilling) 2.95E-02 kg 1.75E-02 1.07E-03

Hydrochloric acid（10%） 7.50E-02 kgDistillation residue 1.80E-01 kg

Total 3.57E+01 2.71E+00

Weight (kg) Calorific value (MJ/kg)

Equivalent product calorific value (MJ/kg)

Equivalent product weight (kg)

Light oil 0.108 42.1 Naphtha: 48.7 0.0933

Medium gravity oil 0.0137 45.2 A-class heavy oil: 39.1 0.0159

Heavy oil 0.168 45.5 C-class heavy oil: 41.7 0.184

Distillation residue 0.180 17.0 Coal: 26.6 0.115

Hydrochloric acid（10%） 0.0750 Hydrochloric acid (35%): 0.0214

Pure water: 0.0536

62

The respective inventory data are as shown below.

Table 5-57. Inventory data for naphtha purification and combustion

Table 5-58. Inventory data for A-class heavy oil purification and combustion

Table 5-59. Inventory data for C-class heavy oil purification and combustion

Table 5-60. Inventory data for coal mining and combustion

Table 5-61. Inventory data for hydrochloric acid production



Input Others Naphtha combustion 9.33E-02 kg 4.76E+00 3.31E-01Total 4.76E+00 3.31E-01



Input Others A-class heavy oil combustion 1.59E-02 kg 8.07E-01 5.79E-02

Total 8.07E-01 5.79E-02



Input Others C-class heavy oil combustion 1.84E-01 kg 8.41E+00 6.25E-01

Total 8.41E+00 6.25E-01



Input Others Fuel coal combustion 1.15E-01 kg 3.11E+00 2.85E-01

Total 3.11E+00 2.85E-01



Input Others Hydrochloric acid(35%) 2.14E-02 kg 7.61E-01 6.85.E-02

Pure water 5.36E-02 kg 2.18E-03 1.74.E-04Total 8.32E-01 6.87E-02

63

Liquefaction summary


Table 5-62. Environmental load of recycling system for liquefaction


Table 5-63. Environmental load of original system for liquefaction


Table 5-64. Environmental load reduction effect for liquefaction

s



Collection, transport, and baling 1.26E+00 6.97E-02Liquefaction 3.57E+01 2.71E+00Total 3.69E+01 2.78E+00



Collection, transport, and baling 1.26E+00 6.97E-02Bale simple incineration, residue landfilling 3.57E+01 2.71E+00Equivalent naphtha purification and combustion 4.76E+00 3.31E-01Equivalent A-class heavy oil purification and combustion 8.07E-01 5.79E-02Equivalent C-class heavy oil purification and combustion 8.41E+00 6.25E-01Equivalent coal purification and combustion 3.11E+00 2.85E-01Equivalent hydrochloric acid production 8.32E-01 6.87E-02Total 5.49E+01 4.15E+00



Reduction effect (liquefaction) 1.80E+01 1.37E+00

64

Gasification (ammonia production)

The system boundary for gasification (ammonia production) is shown below.

Figure 5-5. System boundary for gasification (ammonia production)



packaging are as shown in Table 5-17. The inventory data for the process of bale sorting, volume reduction

and solidification, and gasification (syngas production), and for the process of manufacturing ammonia

from syngas are as shown below. The plastic containers and packagings that become residues during bale

sorting were treated as residues (landfilling), and were added to the process of bale sorting, volume

reduction and solidification, and gasification (syngas production). Also, the carbon content of plastic

containers and packaging is sold as carbonic acid gas and eventually released into the atmosphere. This

release was added as part of bale incineration (gasification).

Bale input

Gasification furnace/gas

cleaning

Residue processing

Ammonia production

Recycling system

1 kg

0.03 kg



packaging1 kg

Ammonia

Carbonic acid


Original system

1 kg


Natural gas ex traction

Production


1 kg


packaging

0.877 kg


0.047 kg

0.877 kg

1.269 Nm3

Ammonia production Ammonia

Carbonic acid 0.559 Nm3

Carbonic acid 0.711 Nm3


Materials production Roadbed material 0.047 kg

Ammonia production plant

Sorting Recy cled product (gas)


Purified gas from utility gas, etc.

Shredding


2.615 Nm3

65

Table 5-65. Inventory data for sorting to gasification (syngas production)

Table 5-66. Inventory data for ammonia production from syngas



Input Raw material Bale incineration (gasification) 1.00E+00 kg 3.56E+01 2.71E+00

Oxygen 9.54E-01 Nm3 ExcludedNaOH 5.00E-03 kg 8.98E-02 6.61E-03

Utility Power 5.83E-01 kWh 5.58E+00 3.38E-01Utility gas 2.19E-04 MJ 3.14E-04 1.37E-05Light oil component 4.28E-04 L 2.04E-02 1.47E-03Steam 1.43E+00 kg 5.19E+00 3.85E-01Air 2.85E-01 Nm3 ExcludedNitrogen 4.24E-01 Nm3 1.54E+00 9.35E-02Water 8.32E-04 m3 1.94E-03 1.18E-04

Output Generated product Syngas 2.62E+00 Nm3

Others Slag 4.70E-02 kgResidue (landfilling) 3.00E-02 kg 1.78E-02 1.09E-03

Total 4.80E+01 3.53E+00



Input Raw material Syngas 2.62E+00 Nm3Air 4.13E-01 Nm3 ExcludedSteam 1.30E+00 kg 4.69E+00 3.49E-01

Utility Power 8.21E-01 kWh 7.86E+00 4.76E-01Utility gas 8.82E+00 MJ 1.26E+01 5.53E-01


Ammonia 8.76E-01 kgCarbonic acid gas 1.27E+00 Nm3Hydrogen 2.62E-02 Nm3

Total 2.52E+01 1.38E+00

66


The inventory data for collection, transport, and baling of plastic containers and packaging and for

incineration and landfilling of bale are the same as that for the original system in Section 5.1.2. The

inventory data for production of new ammonia, carbonic acid production (not as byproduct), and roadbed

material (crushed stone/gravel) production are as shown below.

Table 5-67. Inventory data new ammonia production

Table 5-68. Inventory data for production of new carbonic acid gas and production of roadbed material

(crushed stone/gravel)

Gasification (ammonia production) summary


Table 5-69. Environmental load of recycling system for gasification (ammonia production)



Input Raw material Utility gas 2.14E+01 Nm3 3.07E+01 1.34E+00Raw material Air 8.12E-01 Nm3 ExcludedRaw material Steam 2.33E+00 kg 8.42E+00 6.26E-01Utility Power 6.00E-01 kWh 5.74E+00 3.48E-01Utility Utility gas 8.82E+00 MJ 1.26E+01 5.54E-01

Output Generated product Ammonia 8.76E-01 kg

Generated product Carbonic acid gas 5.58E-01 Nm3

Generated product Hydrogen 2.63E-02 Nm3

Total 5.75E+01 2.87E+00



Output Generated product Carbonic acid gas 1.40E+00 kg 4.16E+01 1.43E+00

Generated product Shredding, crushing 5.36E-02 JPY 3.09E-03 2.22E-04

Total 4.16E+01 1.43E+00



Collection, transport, and baling 1.26E+00 6.97E-02Syngas production 4.80E+01 3.53E+00Ammonia production 2.52E+01 1.38E+00Total 7.45E+01 4.98E+00

67


Table 5-70. Environmental load of original system for gasification (ammonia production)


Table 5-71. Environmental load reduction effect for gasification (ammonia production)



Collection, transport, and baling 1.26E+00 6.97E-02Bale simple incineration, residue landfilling 3.57E+01 2.71E+00Ammonia production 5.75E+01 2.87E+00Carbonic acid gas production 4.16E+01 1.43E+00Crushed stone/gravel production 3.09E-03 2.22E-04Total 1.36E+02 7.09E+00



Reduction effect (gasification (ammonia production)) 6.16E+01 2.11E+00

68

Gasification (combustion)

The system boundary for gasification (combustion) is shown below.

Figure 5-6. System boundary for gasification (combustion)



packaging are as shown in Table 5-17. The process of manufacturing and purification of syngas, after bale

sorting and volume reduction and solidification, was considered as one process, and the inventory data are

as shown below. The plastic containers and packagings that become residues during bale sorting were

treated as residues (landfilling), and were added to the process. Also, the carbon content of plastic

containers and packaging is sold as carbonic acid gas and eventually released into the atmosphere. This

release was added as part of bale incineration (gasification).

Bale input

Gasification, melting

Residue processing

Gas purification (desulfurization/drying)

Recycling system

1 kg

0.03 kg



packaging1 kg


Original system

1 kg



1 kg


packaging

0.509 liters19.104 MJ


0.00001 kg

19.104 MJ

Heav y oil

Sorting Recy cled product (gas) fuel use

Purification, etc.


Gas cooling, cleaning

Gas/fuel use


Materials production Roadbed material 0.00001 kgShredding

69

Table 5-72. Inventory data for sorting to gasification (fuel use)


The inventory data for collection, transport, and baling of plastic containers and packaging and for

incineration and landfilling of bale are the same as that for the original system in Section 5.1.2. The

inventory data for production of new heavy oil (C-class heavy oil) and roadbed material (crushed

stone/gravel) are as shown below.

Table 5-73. Inventory data for production of new heavy oil and roadbed material

Gasification (combustion) summary


Table 5-74. Environmental load of recycling system for gasification (combustion)



Input Raw material Bale incineration (gasification) 1.00E+00 kg 3.56E+01 2.71E+00

Limestone 2.00E-03 kg 1.20E-04 8.02E-06Utility Power 2.10E-01 kWh 2.01E+00 1.22E-01

Light oil component 4.38E-02 MJ 4.76E-02 3.43E-03LNG 1.65E-01 MJ 2.15E-01 1.00E-02Coke 5.84E-02 MJ 8.71E-02 7.81E-03Nitrogen 7.00E-03 Nm3 2.55E-02 1.54E-03Water 5.01E-03 m3 1.16E-02 7.11E-04

Output Generated product Syngas 1.91E+01 MJ

Others Slag 1.00E-05 kgResidue (landfilling) 3.00E-02 kg 1.78E-02 1.09E-03

Total 3.80E+01 2.85E+00



Output Generated product C-class heavy oil 5.09E-01 L 2.33E+01 1.73E+00

Generated product Shredding, crushing 1.14E-05 JPY 6.58E-07 4.73E-08

Total 2.33E+01 1.73E+00



Collection, transport, and baling 1.26E+00 6.97E-02Syngas, gas combustion 3.80E+01 2.85E+00Total 3.93E+01 2.92E+00

70


Table 5-75. Environmental load of original system for gasification (combustion)


Table 5-76. Environmental load reduction effect for gasification (combustion)



Collection, transport, and baling 1.26E+00 6.97E-02Bale simple incineration, residue landfilling 3.57E+01 2.71E+00C-class heavy oil production, combustion 2.33E+01 1.73E+00Crushed stone/gravel production 6.58E-07 4.73E-08Total 6.03E+01 4.52E+00



Reduction effect (gasification (combustion)) 2.10E+01 1.59E+00

71

Blast furnace reduction (substitute for coke)

The system boundary for blast furnace reduction (substitute for coke) is shown below.

Figure 5-7. System boundary for blast furnace reduction (substitute for coke)



1 kg


particles


0.23 kg

Recycling system


Coke ov en

Blast furnace


Iron ore

Coke

Hy drocarbon oil

Pig iron


Purification, etc.



Gas

Benzene 0.397 kgToluene 0.113 kgXy lene 0.056 kg

Light oil component

Tar component

Oil coke 0.619 kg

BTX separation

C-class heavy oil0.516 kg

BTX separation


Purification, etc.

Coal resource ex traction Oil coke 0.014 kg

0.77 kg

77.3 kg

447MJ

1.7 kg


1 kg

Original system


Coke ov en Blast furnaceMaterials

production

Iron ore

Coke

Gas

Pig ironRaw coalCoal resource

ex traction

Purification, etc.




input

Hy drocarbon oil


Light oil component

Tar component

Oil coke 0.633 kg

BTX separation


77.3 kg

445MJ

1.74 kg

C-class heavy oil 0.031L(2.0 MJ)

72


Since blast furnace reduction residues are processed through simple incineration or energy recovery,

environmental load for each residue processing method was computed.

Simple incineration

The inventory data for simple incineration of residues are as shown below.

Table 5-77. Inventory data for simple incineration of 1 kg of residues

RPF use

The inventory data for production of RPF from residues are as shown below.

Table 5-78. Inventory data for production of RPF from 1 kg of residues

The inventory data for incineration and use/ residue landfilling for RPF based on Table 4-16 are as

shown below.

Table 5-79. Inventory data for incineration and use/ residue landfilling of 0.76 kg of RPF



Input Raw material Residue incineration 1.00E+00 kg 3.50E+01 2.64E+00Utility Power 1.30E-02 kWh 1.24E-01 7.54E-03Utility LPG 2.00E-03 MJ 2.31E-03 1.52E-04Utility B-class heavy oil 2.69E-03 MJ 2.97E-03 2.23E-04


Total 3.53E+01 2.66E+00



Input Raw material RPF raw material 1.00E+00 kgUtility Power 1.30E-01 kWh 1.24E+00 7.52E-02







Total 2.27E+01 1.72E+00

73


are as shown below.



single-fuel fired boilers used by paper manufacturers, etc., it was considered as a substitute for coal.

In this case, weight of substituted coal for 1 kg of RPF was computed by taking into account an 88%

boiler efficiency for RPF combustion (data from PWMI) and a 90% boiler efficiency for coal combustion

(data from PWMI):

Coal = 29,782 kJ/kg (RPF) × 0.88 ÷ 0.9 ÷ (26,600 kJ/kg (Coal) × 0.975) ＝ 1.12 kg Note: Net heating value (lower heating value) = Gross heating value (higher heating value) × 0.975

The inventory data for combustion of coal substituting 0.76 kg of RPF are as shown below.


Accordingly, the environmental load for RPF is the value obtained by deducting the environmental load

for coal combustion from the environmental load for manufacturing and using RPF.

Table 5-82. Environmental load for RPF use of residues in blast furnace reduction





Total 9.92E-01 5.80E-02




Total 2.31E+01 2.12E+00



RPF production 1.24E+00 7.52E-02RPF incineration and use/ residue landfilling 2.27E+01 1.72E+00Simple incineration/residue landfilling of sorted residues 9.92E-01 5.80E-02Combustion of coal (RPF substitution effect) -2.31E+01 -2.12E+00Total 1.91E+00 -2.51E-01

74

Cement calcination

The inventory data for manufacture of cement raw fuel from residues are as shown below.

Table 5-83. Inventory data for manufacturing cement raw fuel from 1 kg of residues

The inventory data for incineration and use / residue landfilling of cement raw material based on Table

4-16 are as shown below.

Table 5-84. Inventory data for incineration and use / residue landfilling of 0.89 kg of cement raw material


are as shown below.


Assuming that 1 kg of manufactured cement raw fuel is substituted by coal, we calculated the amount of

coal to substitute 1 kg of cement raw fuel as follows:



Input Raw material Input material 1.00E+00 kgUtility Power 1.57E-01 kWh 1.50E+00 9.10E-02Utility Light oil component 3.80E-02 MJ 4.13E-02 2.98E-03

Output Generated product Cement raw fuel 7.60E-01 kg




Input Raw material Cement raw fuel incineration 7.60E-01 kg 2.26E+01 1.72E+00


Total 2.27E+01 1.72E+00





Total 9.92E-01 5.80E-02

75

Coal ＝ 29,782 kJ/kg (cement raw fuel) ÷ (26,600 kJ/kg (coal) × 0.975) ＝1.15 kg Note: Net heating value (lower heating value) = Gross heating value (higher heating value) × 0.975

The inventory data for combustion of coal substituting 0.76 kg of cement raw fuel are as shown below.


Accordingly, the environmental load for cement raw fuel is the value obtained by deducting the

environmental load for coal combustion from the environmental load for manufacturing and using cement

raw fuel.

Table 5-87. Environmental load for cement calcination of residues in blast furnace reduction


The inventory data for incineration with power generation of residues at 12.81% efficiency are as shown

below. Power generation from incineration of 1 kg of residues was computed as follows based on the power

generation efficiency and the unit calorific value from Table 4-18:

Power generation ＝ 35.0 MJ/kg (residue calorific value) ÷ 3.6 MJ/kWh (power conversion) × 12.81%

(power generation efficiency) ＝ 1.24 kWh/kg.

Table 5-88. Inventory data for incineration with power generation for 1 kg of residues




Total 2.36E+01 2.15E+00



Cement raw fuel production 1.54E+00 9.40E-02Cement raw fuel incineration and use/residue landfilling 2.27E+01 1.72E+00Simple incineration/residue landfilling of sorted residues 9.92E-01 5.80E-02Combustion of coal (cement raw fuel substitution effect) -2.36E+01 -2.15E+00Total 1.67E+00 -2.42E-01



Input Raw material Residue incineration 1.00E+00 kg 3.50E+01 2.64E+00Utility Power (internal use) 1.26E-02 kWh 0.00E+00 0.00E+00Utility Utility gas 1.58E-02 MJ 2.26E-02 9.89E-04Utility A-class heavy oil 2.72E-03 MJ 3.07E-03 2.20E-04



76

It was assumed that the generated power is substituted by the grid power, which was calculated by

subtracting the power used within the plant from the generated power:

Grid power ＝ Power generation － Power used within the plant ＝ 1.24 kWh – 0.0126 kWh＝ 1.23

kWh

The inventory data for grid power substituting 1.24 kWh of generated power are as shown below.

Table 5-89. Inventory data for 1.2 kWh of grid power

Accordingly, the environmental load data for incineration with power generation is the value obtained by

deducting the value for grid power from the environmental load data for incineration with power

generation.

Table 5-90. Environmental load for incineration with power generation of residues in blast furnace

reduction

Environmental load of residues

The environmental load related to the processing of residues was calculated by taking into account the

environmental load of each method according to the residue composition ratio shown in Table 3-2 and by

combining the environmental load of direct landfilling of metals.

Table 5-91. Environmental load for processing of 0.23 kg of residues in blast furnace reduction



Output Generated product Grid power 1.23E+00 kWh 1.18E+01 7.15E-01

Total 1.18E+01 7.15E-01



Incineration with power generation, residue landfilling 7.02E+01 2.64E+00Grid power (incineration with power generation substitution effect) -1.18E+01 -7.15E-01

Total 2.34E+01 1.93E+00



Simple incineration 3.59E-01 2.70E-02RPF use 6.76E-02 -8091E-03Cement raw fuel 1.51E-01 -2.91E-02Incineration with power generation 3.59E-01 2.70E-02Direct landfilling 5.61E-04 1.46E-03Total 9.81E-01 3.11E-02

77



packaging are as shown in Table 5-17. The inventory data for the process of manufacturing blast furnace

reducing agent particles from bale are as shown below.

Table 5-92. Inventory data for the process of manufacturing blast furnace reducing agent particles from bale

Utility during the process of manufacturing pig iron using the blast furnace reducing agent particles

produced from bale was omitted as in the 2007 JCPRA Report. The inventory data for the process are as

shown below.

Table 5-93. Inventory data for the process of manufacturing pig iron using the blast furnace reducing agent

particles

The ratio of hydrocarbon oil coal tar and light oil, ratio of BTX separation process, and environmental

load for BTX separation were based on the 2007 JCPRA Report. The inventory data for the hydrocarbon oil

separation are as follows.




COG 7.00E-03 Nm3 0.00E+00 5.89E-03Kerosene 8.00E-03 L 3.16E-01 2.24E-02Light oil component 4.00E-03 L 1.65E-01 1.19E-02Water 1.70E-01 kg 3.95E-04 2.42E-05

OutputGenerated product

Blast furnace reducing agent particles

7.73E-01 kg

Others Residues (ER, etc.) 2.27E-01 kg 9.81E-01 3.11E-02Total 4.25E+00 2.40E-01



Input Raw material


1.00E+00 kg 3.02E+01 2.30E+00

Raw coal 5.50E+01 kg 1.30E+03 1.17E+02

Iron ore X kg


Gas 5.78E+02 kgHydrocarbon oil 2.20E+00 kgPig iron 1.00E+02 kg

Total 1.33E+03 1.19E+02

78

Table 5-94. Inventory data for BTX separation

Comparing the amount of BTX generated from hydrocarbon oil for the recycling system and for the

original system mentioned below, the amount generated from the original system was larger. Therefore, to

compensate for the difference, the environmental load for new BTX production was added to the recycling

system.

The amounts of newly produced BTX (benzene, toluene, and xylene) were computed from the difference

between the recycling system and original system as follows:

・BTX (benzene) ＝ 0.41 kg (benzene, original) － 0.40 kg (benzene, recycling)

＝ 0.009 kg

・BTX (toluene) ＝ 0.12 kg (toluene, original) － 0.11 kg (toluene, recycling)

＝ 0.003 kg

・BTX (xylene) ＝ 0.058 kg (xylene, original) － 0.057 kg (xylene, recycling)

＝ 0.001 kg

Accordingly, the inventory data for new BTX production are as shown below.

Table 5-95. Inventory data for new BTX production



Input Raw material Hydrocarbon oil 1.70E+00 kg


BTX 5.66E-01 kg 1.66E+00 1.19E-01Benzene 3.97E-01 KgToluene 1.13E-01 kgXylene 5.67E-02 kg

Oil coke 6.19E-01 kgC-class heavy oil 5.16E-01 kg

Total 1.66E+00 1.19E-01




Benzene 9.02E-03 kg6.67E-01 5.07E-02Toluene 2.58E-03 kg

Xylene 1.29E-03 kgTotal 6.67E-01 5.07E-02

79

As with BTX, the difference for oil coke from hydrocarbon oil was also compensated for in the recycling

system. The amount of newly produced oil coke was computed from the difference between the recycling

system and original system as follows:

Oil coke (from hydrocarbon oil) ＝ 0.633 kg (original) － 0.619 kg (recycling) ＝ 0.014 kg

The inventory data for new oil coke production are as shown below.

Table 5-96. Inventory data for new oil coke production


The inventory data for collection, transport, and baling of plastic containers and packaging in the original

system are as shown in Table 5-17. The inventory data for simple incineration and residue landfilling of

bale are as shown in Table 5-21.

The inventory data for manufacturing 77.3 kg of pig iron assuming that raw coal was substituted with

blast furnace reducing agent particles are as shown below.

Table 5-97. Inventory data for pig iron production



Output Generated product Oil coke 1.41E-02 kg 7.10E-01 5.31E-02

Total 7.10E-01 5.31E-02



Input Raw material Raw coal 1.27E+03 MJ 1.34E+03 1.20E+02Iron ore X kg

Output Generated product Gas 4.45E+02 MJ

Output Generated product Hydrocarbon oil 1.74E+00 kg

Output Generated product Pig iron 7.73E+01 kg

Total 1.34E+03 1.20E+02

80


load for BTX separation were based on the 2007 JCPRA Report. The inventory data for the hydrocarbon oil

separation are as follows.


The difference in calorific value due to gas was assumed to be substituted by gas generated from C-class

heavy oil boiler:

C-class heavy oil (gas component) = 446.78 MJ (recycling) － 445.16 MJ (original) ＝ 1.62 MJ

Based on boiler efficiency of 90% and C-class heavy oil unit calorific value of 41.7 MJ/L: 0.43 L

Also, C-class heavy oil from hydrocarbon oil was computed from the difference between the recycling

system and original system.

C-class heavy oil (component from hydrocarbon oil) = 0.516 kg (recycling) － 0.527 kg (original)＝－

0.011 kg ＝－0.012 L Note: C-class heavy oil density = 0.940kg/L

C-class heavy oil (total) = 0.043 L (gas component) － 0.012 L (component from hydrocarbon oil) ＝

0.031 L

Accordingly, the inventory data for C-class heavy oil purification and combustion are as shown below.




Input Raw material Hydrocarbon oil 1.74E+00 kg


BTX 5.79E-01 kg 1.69E-02 1.15E-03Benzene 4.06E-01 kgToluene 1.16E-01 kgXylene 5.80E-02 kg

Oil coke 6.33E-01 kgC-class heavy oil 5.27E-01 kg

Total 1.69E-02 1.15E-03



Output Generated product C-class heavy oil 3.06E-02 L 1.40E+00 1.04E-01

Total 1.40E+00 1.04E-01

81

Blast furnace reduction (substitute for coke) summary


Table 5-100. Environmental load of recycling system for blast furnace reduction (substitute for coke)


Table 5-101. Environmental load of original system for blast furnace reduction (substitute for coke)


Table 5-102. Environmental load reduction effect for blast furnace reduction (substitute for coke)



Collection and transport 1.26E+00 6.97E-02Blast furnace reducing agent particlesProduction 4.25E+00 2.40E-01

Pig iron production 1.33E+03 1.19E+02Hydrocarbon oil separation 1.66E+00 1.19E-01New BTX purification 6.67E-01 5.07E-02New oil coke purification 7.10E-01 5.31E-02Total 1.34E+03 1.20E+02



Collection, transport, and baling 1.26E+00 6.97E-02Simple incineration, residue landfilling 3.57E+01 2.71E+00Pig iron production 1.34E+03 1.20E+02Hydrocarbon oil separation 1.69E-02 1.15E-03C-class heavy oil purification 1.40E+00 1.04E-01Total 1.37E+03 1.23E+02



Reduction effect 3.45E+01 3.15E+00

82

Blast furnace reduction (substitute for pulverized coal)

The system boundary for blast furnace reduction (substitute for pulverized coal) is shown below.

Figure 5-8. System boundary for blast furnace reduction (substitute for pulverized coal)


Handling of residues for blast furnace reduction (substitute for pulverized coal) was the same as that for

blast furnace reduction (substitute for coke).



packaging are as shown in Table 5-17. The inventory data for the process of manufacturing blast furnace

reducing agent particles from bale are the same as that shown in Table 5-92.

Utility for the process of manufacturing pig iron using the blast furnace reducing agent particles

produced from bale was omitted as in the 2007 JCPRA Report. The inventory data for the process are as

shown below.

Recycling system




1 kgBaling Transport Bale

input


particles

0.23 kg

Blast furnace

Iron ore

Pig iron

Gas0.77 kg

77.3 kg

399MJ



Original systemPlastic containers

and packaging1 kg



input

Purification, etc.






Blast furnace

Iron ore

Pig iron

Gas

77.3 kg

396MJ9.28 kg

Gas


83

Table 5-103. Inventory data for the process of manufacturing pig iron using the blast furnace reducing

agent particles



system are as shown in Table 5-17. The inventory data for simple incineration / residue landfilling of bale

are as shown in Table 5-21.

The inventory data for manufacturing 77.3 kg of pig iron assuming that pulverized coal was substituted

with blast furnace reducing agent particles are as shown below.

Table 5-104. Inventory data for pig iron production


heavy oil boiler:

C-class heavy oil (gas component) = 398.96 MJ (recycling) － 396.37 MJ (original) ＝ 2.590 MJ

Based on boiler efficiency of 90% and C-class heavy oil unit calorific value of 41.7 MJ/L: 0.069 L

Accordingly, the inventory data for C-class heavy oil purification and combustion are as shown below.




Input Raw material


7.73E-01 kg 3.02E+01 2.30E+00

Raw coal 3.53E+02 MJ 2.29E+02 2.10E+01

Iron ore X kg


Gas 3.99E+02 MJPig iron 7.73E+01 kg

Total 2.59E+02 2.33E+01



Input Raw material Pulverized coal 3.88E+02 MJ 2.51E+02 2.30E+01Iron ore X kg

Output Generated product Gas 3.96E+02 MJ

Output Generated product Pig iron 7.73E+01 kg

Total 2.51E+02 2.30E+01



Output Generated product C-class heavy oil 6.90E-02 L 3.16E+00 2.35E-01

Total 3.16E+00 2.35E-01

84

Blast furnace reduction (substitute for pulverized coal) summary


Table 5-106. Environmental load of recycling system for blast furnace reduction (substitute for pulverized

coal)


Table 5-107. Environmental load of original system for blast furnace reduction (substitute for pulverized

coal)


Table 5-108. Environmental load reduction effect for blast furnace reduction (substitute for pulverized coal)



Collection and transport 1.26E+00 6.97E-02Blast furnace reducing agent particlesProduction 4.23E+00 2.39E-01

Pig iron production 2.59E+02 2.33E+01Total 2.64E+02 2.36E+01



Collection, transport, and baling 1.26E+00 6.97E-02Simple incineration, residue landfilling 3.57E+01 2.71E+00C-class heavy oil purification 3.16E+00 2.35E-01Pig iron production 2.51E+02 2.30E+01Total 2.91E+02 2.60E+01




85



The system boundary for coke-oven chemical material is shown below.

Figure 5-9. System boundary for coke-oven chemical material

Recycling system

*Practical unit standardized base on coke production volume.



1 kg


particles

Residue landfilling

0.04 kg

Coke ov en

Hy drocarbon oil

Coke


Gas


Light oil component

Tar component

BTX separation

0.92 kg

0.183 kg

0.366 kg

0.366 kg

C-class heavy oil0.104kg

Oil coke 0.125 kg

Original system

Raw coal Coke ov en

Hy drocarbon oil

Coke

Gas


Light oil component

Tar component

BTX separation

0.183 kg

0.053 kg

0.015 g


Oil coke 0.006 kg




packaging1 kg



input

Purification, etc.Crude oil resource

collection C-class heavy oil0.0994L


BTX separation


Coal resource ex traction Oil coke 0.119 kgPurification, etc.

Purification, etc.

86



packaging are as shown in Table 5-17. The inventory data for the process of manufacturing coke-oven

chemical material particles from bale are as shown below.

Table 5-109. Inventory data for the process of manufacturing coke-oven chemical material particles from

bale

Manufactured coke-oven chemical material particles were inputted into the coke oven and decomposed

into coke, gas, and hydrocarbon oil at a ratio of 2:4:4. The inventory data for the formation of coke, gas,

and hydrocarbon oil are as shown below.

Table 5-110. Inventory data for the process of producing coke, gas, and hydrocarbon oil from coke-oven

chemical material particles

Also, hydrocarbon oil is divided into tar component and light oil component at a ratio of 25:15, and the

light oil component is subjected to BTX separation. Environmental load for BTX separation was based on

the 2007 JCPRA Report.





Coke-oven chemical material particles 9.15E-01 kg

Others Residue (landfilling) 4.00E-02 kg 2.38E-02 1.45E-03Total 2.84E+00 1.72E-01



Input

Raw material Coke-oven chemical material particles

9.15E-01 kg 3.58E+01 2.72E+00

UtilityPower 1.32E-02 kWh 1.26E-01 7.64E-03

COG 2.21E+00 MJ 0.00E+00 8.90E-02


Hydrocarbon oil 3.66E-01 MJCoke 1.83E-01 kgGas 3.66E-01 kg

Total 3.59E+01 2.81E+00

87






For the original system, raw coal was inputted into the coke oven and decomposed into coke, gas, and

hydrocarbon oil. The inventory data for the process are as shown below.

Table 5-112. Inventory data for producing coke, gas, and hydrocarbon oil from raw coal


load for BTX separation were based on the 2007 JCPRA Report.

The inventory data for BTX separation from hydrocarbon oil are as follows.




Input Raw material Hydrocarbon oil 3.66E-01 kg


BTX 1.37E-01 kg 4.63E-01 3.15E-02Oil coke 1.25E-01 kgC-class heavy oil 1.04E-01 kg

Total 4.63E-01 3.15E-02



Input Raw material Raw coal 2.51E-01 kg 7.68E+00 6.89E-01

UtilityPower 3.61E-03 kWh 3.45E-02 2.09E-03COG 6.04E-01 Nm3 0.00E+00 2.44E-02

Output

Generated product Hydrocarbon oil 1.50E-02 kg

Generated product Coke 1.83E-01 kg

Generated product Gas 5.26E-02 kg

Total 7.71E+00 7.16E-01



Input Raw material Hydrocarbon oil 1.50E-02 kg


BTX 5.04E-03 kg 1.69E-02 1.15E-03Oil coke 5.00E-03 kgC-class heavy oil 5.00E-03 kg

Total 1.69E-02 1.15E-03

88


heavy oil boiler:

C-class heavy oil (gas component) = (0.366 kg － 0.053 kg) ÷ 0.40 kg/m3 (gas density) × 21.1 MJ/m3

(gas unit calorific value) × 100 ÷ 90 (boiler efficiency) ÷ 41.7 MJ/L (C-class heavy oil unit calorific value)

＝ 0.440 L

The newly produced C-class heavy oil was computed from the difference between the gas component

and the C-class heavy oil from hydrocarbon oil for the recycling system and that of the original system.

C-class heavy oil (component from hydrocarbon oil) = 0.104 kg (recycling) － 0.005 kg (original)＝

0.099 kg ＝ 0.107 L Note: C-class heavy oil density = 0.940 kg/L

C-class heavy oil (total) = 0.440 L (gas component) ＋ 0.107 L (component from hydrocarbon oil) ＝

0.547 L

The inventory data for C-class heavy oil purification and combustion are as shown below.


The amounts of newly produced BTX (benzene, toluene, and xylene) were computed from the difference

between the recycling system and original system as follows:

・BTX (benzene) ＝ 0.108 kg (recycling, benzene) － 0.004 kg (original, benzene)

＝0.105 kg (benzene)

・BTX (toluene) ＝ 0.026 kg (recycling, toluene) － 0.001 kg (original, toluene)

＝0.025 kg (toluene)

・BTX (xylene) ＝ 0.0027 kg (recycling, xylene) － 0.0005 kg (original, xylene)

＝ 0.0022 kg (xylene)

The inventory data for new BTX production are as shown below.

Table 5-115. Inventory data for new BTX production




C-class heavy oil(combustion) 1.84E+01 MJ 2.50E+01 1.86E+00

Total 2.50E+01 1.86E+00




Benzene 1.05E-01 kg6.84E+00 5.21E-01Toluene 2.51E-02 kg

Xylene 2.24E-03 kgTotal 6.84E+00 5.21E-01

89

The newly produced oil coke was also computed from the difference between the recycling system and

original system as follows:

Oil coke (from hydrocarbon oil) ＝ 0.125 kg (recycling) － 0.005 kg (original) ＝ 0.119 kg

The inventory data for new oil coke production are as shown below.

Table 5-116. Inventory data for new oil coke production

Coke-oven chemical material summary


Table 5-117. Environmental load of recycling system for coke-oven chemical material


Table 5-118. Environmental load of original system for coke-oven chemical material


Table 5-119. Environmental load reduction effect for coke-oven chemical material



Output Generated product Oil coke 1.20E-01 kg 6.02E+00 4.51E-01

Total 6.02E+00 4.51E-01



Collection and transport 1.26E+00 6.97E-02Granulated plastic production 3.35E+00 6.86E-01Coke production 3.59E+01 2.81E+00Hydrocarbon oil separation 4.63E-01 3.15E-02Total 4.05E+01 3.09E+00



Collection, transport, and baling 1.26E+00 6.97E-02Simple incineration, residue landfilling 3.57E+01 2.71E+00Coke production 7.71E+00 7.16E-01Hydrocarbon oil separation 1.69E-02 1.15E-03C-class heavy oil purification, combustion 2.50E+01 1.86E+00BTX sepraration 6.84E+00 5.21E-01Oil coke purufication, combustion 6.02E+00 4.51E-01Total 8.26E+01 6.33E+00




90

5.3 Energy recovery

RPF use

RPF use (75% yield)

The system boundary for RPF use (75% yield) is shown below.

Figure 5-10. System boundary for RPF use (75% yield)



packaging are as shown in Table 5-17. The inventory data for the process of manufacturing RPF from bale

are as shown below.

Table 5-120. Inventory data for the process of manufacturing RPF from bale

Recycling system

1.14 kg＝3.0MJ

Original system

* Practical unit standardized based on calorific value of RPF, with a consideration of boiler efficiency, etc.



1 kg


RPF production

Incineration disposal

0.19 kg

RPF 0.77 kg＝3.0MJ


1 kg



input


etc.





Others Residues 2.27E-01 kgTotal 1.80E+00 1.09E-01

91

The inventory data for combustion of manufactured RPF as fuel and landfilling of residues are as shown

below.

Table 5-121. Inventory data for simple incineration and residue landfilling of RPF

Residues in Table 5-120 are processed through simple incineration, and inventory data are as shown

below.

Table 5-122. Inventory data for simple incineration of residues






single-fuel fired boilers used by paper manufacturers, etc., it was considered as a substitute for coal. In this

case, the weight of substituted coal for 1 kg of RPF was computed by taking into account an 88% boiler

efficiency for RPF combustion (data from PWMI) and a 90% boiler efficiency for coal combustion (data

from PWMI):





Output Utility Power 1.00E-02 kWh 9.62E-02 5.83E-03Utility LPG 1.55E-03 MJ 1.78E-03 1.17E-04Utility B-class heavy oil 2.08E-03 MJ 2.30E-03 1.72E-04Others Residue (landfilling) 2.40E-02 kg 1.42E-02 8.70E-04

Total 3.03E+01 2.31E+00



Input Raw material Residue incineration 2.27E-01 kg 5.36E+00 4.04E-01

Output Utility Power 2.95E-03 kWh 2.82E-02 1.71E-03Utility LPG 4.55E-04 MJ 5.24E-04 3.45E-05Utility B-class heavy oil 6.11E-04 MJ 6.75E-04 5.06E-05Others Residue (landfilling 7.04E-03 kg 4.18E-03 2.56E-04

Total 5.40E+00 4.06E-01

92

Accordingly, the inventory data for coal incineration are as shown below.

Table 5-123. Inventory data for coal combustion

RPF use (75% yield) summary


Table 5-124. Environmental load of recycling system for RPF use (75% yield)


Table 5-125. Environmental load of original system for RPF use (75% yield)


Table 5-126. Environmental load reduction effect for RPF use (75% yield)

Active mass Energy resource consumption (MJ)


Fuel coal (combustion) 1.14E+00 kg 3.09E+01 2.83E+00



Collection and transport 1.26E+00 6.97E-02RPF production (75% yield) 1.80E+00 1.09E-01RPFIncineration, Residue landfilling 3.03E+01 2.31E+00Residue incineration, landfilling 5.40E+00 4.06E-01Total 3.88E+01 2.89E+00



Collection and transport 1.26E+00 6.97E-02Simple incineration, landfilling 3.57E+01 2.71E+00Coal incineration 3.09E+01 2.83E+00Total 6.79E+01 5.61E+00



Reduction effect (RPF use (75% yield)) 2.91E+01 2.72E+00

93

RPF use (89% yield)

The system boundary for RPF use (89% yield) is shown below.

Figure 5-11. System boundary for RPF use (89% yield)



packaging are as shown in Table 5-17. The inventory data for the process of manufacturing RPF from bale

are as shown below.

Table 5-127. Inventory data for the process of manufacturing RPF from bale

The inventory data for combustion of manufactured RPF as fuel and landfilling of residues are as shown

below.

Table 5-128. Inventory data for simple incineration and residue landfilling of RPF

Recycling system

1.34 kg＝3.5MJ

Original system

* Practical unit standardized based on calorific value of RPF, with a consideration of boiler efficiency, etc.



1 kg


RPF production


0.050 kg

RPF 0.91 kg＝3.6MJ


1 kg



input


etc.










Total 3.57E+01 2.71E+00

94

Residues in Table 5-127 are processed through landfilling since they are metals, and the inventory data

are as shown below.

Table 5-129. Inventory data for landfilling of residues





Weight of substituted coal for 1 kg of RPF was computed by taking into account an 88% boiler

efficiency for RPF combustion (data from PWMI) and a 90% boiler efficiency for coal combustion (data

from PWMI):


Accordingly, the inventory data for coal incineration are as shown below.

Table 5-130. Inventory data for coal incineration

RPF use (89% yield) summary


Table 5-131. Environmental load of recycling system for RPF use (89% yield)



Input Raw material Residue (landfilling 8.97E-02 kg 5.33E-02 3.26E-03

Total 5.33E-02 3.26E-03






Collection and transport 1.26E+00 6.97E-02Reduction effect (RPF use (89% yield)) 1.80E+00 1.09E-01

RPFIncineration, Residue landfilling 3.57E+01 2.71E+00Direct landfilling of residues 5.33E-02 3.26E-03Total 3.89E+01 2.90E+00

95


Table 5-132. Environmental load of original system for RPF use (89% yield)


Table 5-133. Environmental load reduction effect for RPF use (89% yield)






Reduction effect (RPF use (89% yield)) 3.45E+01 3.22E+00

96

Cement calcination

Cement calcination (75% yield)

The system boundary for cement calcination (75% yield) is shown below.

Figure 5-12. System boundary for cement calcination (75% yield)



packaging are as shown in Table 5-17. The inventory data for the process of manufacturing

secondary-crushing plastic from bale are as shown below.

Table 5-134. Inventory data for the process of manufacturing secondary-crushing plastic from bale

Recycling system

Original system



1 kg




0.19 kg

Secondary-crushing plastic 0.77 kg＝3.0MJ


1 kg



input

1.17 kg＝3.0MJCoal resource extraction CoalPurification,

etc.

* Practical unit standardized based on calorific value of cement raw material (secondary-crushing plastic).



Input Raw material Bale 1.00E+00 kgUtility Power 1.90E-01 kWh 1.82E+00 1.10E-01Utility Light oil component 9.60E-04 L 3.97E-02 2.86E-03


Secondary-crushing plastic 7.73E-01 kg


97

The inventory data for use of the manufactured secondary-crushing plastic as fuel in cement production,

and landfilling of residues are as shown below.

Table 5-135. Inventory data for simple incineration and residue landfilling of secondary-crushing plastic

Residues in Table 5-134 are processed through simple incineration, and the inventory data are as shown

below.

Table 5-136. Inventory data for simple incineration of residues





The manufactured secondary-crushing plastic was considered as substitute for coal. In this case, the

weight of substituted coal for 1 kg of secondary-crushing plastic was computed as follows:

Coal = 339,112 kJ/kg (secondary-crushing plastic) ÷ (26,600 kJ/kg (Coal) × 0.975) ＝ 1.51 kg Note: Net heating value (lower heating value) = Gross heating value (higher heating value) × 0.975

Accordingly, the inventory data for coal combustion are as shown below.




Input Raw material Secondary-crushing plastic 7.73E-01 kg 3.02E+01 2.30E+00


Total 3.03E+01 2.31E+00



Input Raw material Residue incineration 2.27E-01 kg 5.36E+00 4.04E-01

Output Utility Power 2.95E-03 kWh 2.82E-02 1.71E-03Utility LPG 4.55E-04 MJ 5.24E-04 3.45E-05Utility B-class heavy oil 6.11E-04 MJ 6.75E-04 5.06E-05Others Residue (landfilling 7.04E-03 kg 4.18E-03 2.56E-04

Total 5.40E+00 4.06E-01




98

Cement calcination (75% yield) summary


Table 5-138. Environmental load of recycling system for cement calcination (75% yield)


Table 5-139. Environmental load of original system for cement calcination (75% yield)


Table 5-140. Environmental load reduction effect for cement calcination (75% yield)



Collection and transport 1.26E+00 6.97E-02Secondary-crushing plastic production (75% yield) 1.86E+00 1.13E-01

Secondary-crushing plastic incineration, residue landfilling 3.03E+01 2.31E+00

Residue incineration, landfilling 5.40E+00 4.06E-01Total 3.89E+01 2.90E+00



Collection and transport 1.26E+00 6.97E-02Simple incineration, residue landfilling 3.57E+01 2.71E+00Coal incineration 3.16E+01 2.89E+00Total 6.86E+01 5.68E+00



Reduction effect (cement calcination (75% yield)) 2.97E+01 2.78E+00

99


The system boundary for cement calcination (89% yield) is shown below.

Figure 5-13. System boundary for cement calcination (89% yield)



packaging are as shown in Table 5-17. The inventory data for the process of manufacturing

secondary-crushing plastic from bale are as shown below.

Table 5-141. Inventory data for the process of manufacturing secondary-crushing plastic from bale

The inventory data for use of the manufactured secondary-crushing plastic as fuel in cement production,

and landfilling of residues are as shown below.

Table 5-142. Inventory data for simple incineration and residue landfilling of secondary-crushing plastic

Recycling system

Original system



packaging1 kg




0.050 kg



packaging1 kg



input

1.37 kg＝3.6MJCoal resource extraction CoalPurification,

etc.

* Practical unit standardized based on calorific value of cement raw material (secondary-crushing plastic).



Input Raw material Bale 1.00E+00 kgUtility Power 1.90E-01 kWh 1.82E+00 1.10E-01Utility Light oil component 9.60E-04 L 3.97E-02 2.86E-03


Secondary-crushing plastic 9.10E-01 kg




Input Raw material Secondary-crushing plastic 9.10E-01 kg 3.56E+01 2.71E+00


Total 3.57E+01 2.71E+00

100

Residues in Table 5-140 are processed through landfilling since they are metals, and the inventory data

are as shown below.

Table 5-143. Inventory data for landfilling of residues





The weight of substituted coal for 1 kg of secondary-crushing plastic was computed as follows:

Coal = 339,112 kJ/kg (secondary-crushing plastic) ÷ (26,600 kJ/kg (Coal) × 0.975) ＝ 1.51 kg Note: Net heating value (lower heating value) = Gross heating value (higher heating value) × 0.975

Accordingly, the inventory data for coal combustion are as shown below.


Cement calcination (89% yield) summary


Table 5-145. Environmental load of recycling system for cement calcination (89% yield)



Input Raw material Residue (landfilling 8.97E-02 kg 5.33E-02 3.26E-03

Total 5.33E-02 3.26E-03






Collection and transport 1.26E+00 6.97E-02Secondary-crushing plastic production (89% yield) 1.86E+00 1.13E-01

Secondary-crushing plastic incineration, residue landfilling 3.57E+01 2.71E+00

Direct landfilling of residues 5.33E-02 3.26E-03Total 3.89E+01 2.90E+00

101


Table 5-146. Environmental load of original system for cement calcination (89% yield)


Table 5-147. Environmental load reduction effect for cement calcination (89% yield)






Reduction effect (cement calcination (89% yield)) 3.53E+01 3.29E+00

102


Incineration with power generation (12.81% power generation efficiency)

The system boundary for incineration with power generation (12.81% power generation efficiency) is

shown below.

Figure 5-14. System boundary for incineration with power generation (12.81% power generation

efficiency)


The inventory data for collection and transport of plastic containers and packaging are as shown below.

Table 5-148. Inventory data for collection and transport of 1 kg of plastic containers and packaging

Power generation from incineration of 1 kg of plastic containers and packaging was computed as follows

based on the power generation efficiency and the unit calorific value of plastic containers and packaging

from Table 4-10:

Power generation ＝ Plastic containers and packaging unit calorific value × power conversion × power

generation efficiency ＝ 35.6 MJ/kg ÷ 3.6 MJ/kWh × 12.81% ＝ 1.27 kWh/kg.



1 kg

Incineration with power generation efficiency

12.81%Power


0.031 kg

1.27 kWh

Recycling system


1 kg



1.25 kWh

Original system

Resource extraction

* Practical unit standardized based on generated energy.With the exclusion of component used within the plant.

Power plant




Input Raw material Plastic containers and packaging

1.00E+00 kg

Output Utility Collection and transport 1.00E+00 kg 8.40E-02 6.00E-03

103

Accordingly, the inventory data for incineration with power generation are as shown below.

Table 5-149. Inventory data for incineration with power generation for 1 kg of plastic containers and

packaging


For the original system, it was assumed that plastic containers and packagings are collected and

transported as combustible waste, and subjected to simple incineration. The inventory data for collection

and transport of plastic containers and packaging are as shown in Table 5-148. The inventory data for

simple incineration and landfilling of 1 kg of plastic containers and packaging are the same as that for

simple incineration and landfilling of 1 kg of bale (Table 5-21).

For the original system, the amount of grid power computed by subtracting the power used within the

plant from the generated power is necessary.

Grid power ＝ Power generation － power used within the plant ＝ 1.27 kWh – 0.0126 kWh＝ 1.25

kWh

The environmental load for grid power is as shown below.

Table 5-150. Environmental load for grid power



Input Raw material Plastic containers and packaging incineration

1.00E+00 kg 3.54E+01 2.71E+00

Utility Power (internal use) 1.26E-02 kWh 0.00E+00 0.00E+00Utility gas 1.58E-02 MJ 2.26E-02 9.89E-04A-class heavy oil 2.72E-03 MJ 3.07E-03 2.20E-04





Grid power 1.25 kWh 1.20E+01 7.27E-01

104

Incineration with power generation (12.81% power generation efficiency) summary


Table 5-151. Environmental load of recycling system for incineration with power generation (12.81%

power generation efficiency)


Table 5-152. Environmental load of original system for incineration with power generation (12.81% power

generation efficiency)


Table 5-153. Environmental load reduction effect for incineration with power generation (12.81% power




Collection and transport 8.40E-02 6.00E-03

Incineration with power generation 3.56E+01 2.71E+00

Total 3.57E+01 2.71E+00




Simple incineration, landfilling 3.57E+01 2.71E+00

Grid power 1.20E+01 7.27E-01

Total 4.78E+01 3.45E+00



Environmental load reduction effect (incineration with power generation) 1.21E+01 7.34E-01

105

Incineration with power generation (25% power generation efficiency)

Current top-class waste-to-energy plants are able to produce power at an efficiency of 25%. We therefore

compared the environmental load reduction effect for 25% efficiency, assuming that the current average of

12.81% can reach that level through future measures to improve efficiency.

The system boundary for incineration with power generation (25% power generation efficiency) is shown

below.

Figure 5-15. System boundary for incineration with power generation (25% power generation efficiency)


The inventory data for collection and transport of plastic containers and packaging are as shown in Table

5-148. Power generation from incineration of 1 kg of plastic containers and packaging was computed as

follows based on the power generation efficiency and the unit calorific value of plastic containers and

packaging.

Power generation ＝ Plastic containers and packaging unit calorific value × power conversion × power

generation efficiency ＝ 35.6 MJ/kg ÷ 3.6 MJ/kWh × 25 % ＝ 2.47 kWh/kg.

Accordingly, the inventory data for incineration with power generation are as shown below.

Table 5-154. Inventory data for incineration with power generation for 1 kg of plastic containers and

packaging



1 kg


efficiency 25%Power


0.031 kg

2.47 kWh

Recycling system


1 kg



2.46 kWh

Original system

Resource extraction

* Practical unit standardized based on generated energy.With the exclusion of component used within the plant.

Power plant




Input Raw material Plastic containers and packaging incineration

1.00E+00 kg 3.54E+01 2.71E+00

Utility Power (internal use) 1.26E-02 kWh 0.00E+00 0.00E+00Utility gas 1.58E-02 MJ 2.26E-02 9.89E-04A-class heavy oil 2.72E-03 MJ 3.07E-03 2.20E-04



106


For the original system, it was assumed that plastic containers and packagings are collected and

transported as combustible waste, and subjected to simple incineration. The inventory data for collection

and transport of plastic containers and packaging are as shown in Table 5-148. The inventory data for

simple incineration and landfilling of 1 kg of plastic containers and packaging are the same as that for

simple incineration and landfilling of 1 kg of bale (Table 5-21).

For the original system, the amount of grid power computed by subtracting the power used within the plant

from the generated power is necessary.

Grid power ＝ Power generation － power used within the plant ＝ 2.47 kWh – 0.0126 kWh＝ 2.46

kWh

The environmental load for grid power is as shown below.

Table 5-155. Environmental load for grid power

Incineration with power generation (25% power generation efficiency) summary


Table 5-156. Environmental load of recycling system for incineration with power generation (25% power




Grid power 2.46 kWh 2.35E+01 1.43E+00





Total 3.57E+01 2.71E+00

107


Table 5-157. Environmental load of original system for incineration with power generation (25% power



Table 5-158. Environmental load reduction effect for incineration with power generation (25% power






Grid power 2.35E+01 1.43E+00

Total 5.94E+01 4.15E+00


CO2 emission (kg - CO2)

Environmental load reduction effect (incineration with power generation) 2.36E+01 1.43E+00

108

Graphic representation of CO2 emissions and CO2 emissions reduction effect for each processing method

6.1 Graph of CO2 emissions and CO2 emissions reduction effect for each processing method

This section presents the CO2 emissions and the CO2 emissions reduction effect, which represents the

measure of environmental load reduction effect, for each processing method, computed in Chapter 5, as bar

graphs. The environmental load reduction effect was interpreted as CO2 emissions being in the negative.

Note that the scale of the vertical axis for the graphs in Figure 6-6 and Figure 6-8 is different from that of

the other graphs.


Returnable pallet (substitute for new resin, simple average case)

Figure 6-1. CO2 emissions and the CO2 emissions reduction effect for returnable pallet

(substitute for new resin)

109


Figure 6-2. CO2 emissions and the CO2 emissions reduction effect for returnable pallet

(substitute for new wood)

110

Feedstock recycling

Liquefaction

Figure 6-3. CO2 emissions and the CO2 emissions reduction effect for liquefaction


Figure 6-4. CO2 emissions and the CO2 emissions reduction effect for gasification (ammonia production)

111


Figure 6-5. CO2 emissions and the CO2 emissions reduction effect for gasification (combustion)


Figure 6-6. CO2 emissions and the CO2 emissions reduction effect for blast furnace reduction

(substitute for coke)

112

Results for blast furnace reduction (substitute for coke) were not suitable for comparison based on the

graph due to the large environmental burden for the pig iron production process compared to other

processes. The graph was re-plotted, therefore, by adding the difference between the recycling system and

the original system to the original system for pig iron production.


(substitute for coke) (pig iron production process is based only on difference)



(substitute for pulverized coal)

113

Likewise, for blast furnace reduction (substitute for pulverized coal), the graph was re-plotted by adding

the difference for the pig iron production process to the recycling system.


(substitute for pulverized coal) (pig iron production process is based only on difference)


Figure 6-10. CO2 emissions and the CO2 emissions reduction effect for coke-oven chemical material

114

Energy recovery

RPF use

RPF use (75% yield)

Figure 6-11. CO2 emissions and the CO2 emissions reduction effect for RPF use (75% yield)

RPF use (89% yield)

Figure 6-12. CO2 emissions and the CO2 emissions reduction effect for RPF use (89% yield)

115

Cement calcination


Figure 6-13. CO2 emissions and the CO2 emissions reduction effect for cement calcination (75% yield)


Figure 6-14. CO2 emissions and the CO2 emissions reduction effect for cement calcination (89% yield)

116


Incineration with power generation (12.81% efficiency)

Figure 6-15. CO2 emissions and the CO2 emissions reduction effect for incineration with power generation

(12.81% efficiency)

Incineration with power generation (25% efficiency)

Figure 6-16. CO2 emissions and the CO2 emissions reduction effect for incineration with power generation

(25% efficiency)

117

6.2 Graphic representation of CO2 emissions and CO2 emissions reduction effect for each

processing method

The bar graphs presented in the previous section, however, do not show details such as which processes

of the recycling system act as substitute for which processes of the original system and in which process

CO2 is emitted. To overcome this limitation, we indicated the CO2 emissions volumes for the original

processes and for the recycling processes serving as substitute in the system boundary diagrams. The

resulting diagrams enable an intuitive grasp of the processes that emit CO2. The level of CO2 emissions was

expressed using three arrow sizes.


Returnable pallet (substitute for new resin, simple average case)

Figure 6-17. Graphic representation of CO2 emissions and CO2 emissions reduction effect for returnable

pallet (substitute for new resin)

Bale input Sorting



Creation of product

(molding, etc.)



Recycling system

1 kg0.51 kg 0.51 kg


Plastic containers

and packaging

1 kg

0.041 kg-CO2 0.022 kg-CO2 0.0073 kg-CO2

Recycled product

0.29 kg-CO2

0.48 kg

0.19 kg-CO21.6 kg-CO2


Cement calcination


Materials(resin)


Pallet(0.0217pcs.)

9.5 kg/pc.


0.21 kg

Creation of product

(molding, etc.)

MaterialsProduction

PE+PP＝0.21 kg


transportPlastic

containers and packaging

1 kg

Coal0.29 kg

Resource extraction


Grid powerPurification, etc.Resource extraction Power plant

0.041 kg-CO2 0.022 kg-CO2 0.0073 kg-CO2 2.7 kg-CO2

0.23 kg

0.11 kg

0.66 kg-CO2

0.37 kg-CO2

0.10 kg

0.26 kg-CO2

0.40 kg-CO2 0.11 kg-CO20.65 kg-CO2

Process (1)

Process (1) substitute

Process (2)


Process (3)

Process (4)

Process (5)

Process (3) substitute 0.055 kg-CO2


Coal0.12 kg

Resource extraction

Materials productionProcess (5) substitute

Original system

0.63 kg-CO2

0.31 kg-CO2

118


Figure 6-18. Graphic representation of CO2 emissions and CO2 emissions reduction effect for returnable

pallet (substitute for new wood)

Bale input Sorting



Creation of product

(molding, etc.)



Recycling system

1 kg0.51 kg 0.51 kg


Plastic containers

and packaging

1 kg

0.041 kg-CO2 0.022 kg-CO2 0.0073 kg-CO2

Recycled product

0.29 kg-CO2

0.48 kg

0.19 kg-CO21.6 kg-CO2


Cement calcination

0.23 kg

0.11 kg

0.66 kg-CO2

0.37 kg-CO2

0.10 kg

0.26 kg-CO2Process (1)

Process (2)

Process (3)

Process (4)

Process (5)


Logging, import

Pallet(0.022pcs.)

30 kg/pc.


0.65 kg

ProcessingRaw wood, lumber


transport


packaging1 kg

Coal0.29 kg

Resourceextraction


Grid powerPurification, etc.Resourceextraction Power plant

0.041 kg-CO2 0.022 kg-CO2 0.0073 kg-CO2 2.7 kg-CO2

0.12 kg-CO2 0.0036 kg-CO2

0.02 kg-CO2





Coal0.12 kg

Resourceextraction


Original system

0.63 kg-CO2

0.31 kg-CO2

119

Feedstock recycling

Liquefaction

Figure 6-19. Graphic representation of CO2 emissions and CO2 emissions reduction effect for liquefaction


Figure 6-20. Graphic representation of CO2 emissions and CO2 emissions reduction effect for gasification

(ammonia production)

Bale input

Sorting

Residue landfilling

Reduction and

solidification

Py rolysis(dechlorination,

thermoly sis, distillation)


1 kg

0.0295 kg

Co-product (hydrochloric acids): 0.075 kg


Plastic containers

and packaging

1 kg

Recycled product (light oil)

Recycled product (medium gravity oil)

Recycled product (heavy oil)

Shipping: 0.014kg→0.62MJ


Co-product(distillation residues): 0.18 kg→3.1MJ

Bale input

Incineration, landfilling1 kg

Resource extraction

Hydrochloric acid production facility 0.075 kg




Hydrochloric acid


1 kg

Plastic containers

and packaging

4.5 MJ equivalentRecy cled product equivalent (Naphtha raw material)

0.62 MJ equivalentRecy cled product equivalent (A-class heavy oil)

7.7 MJ equivalentRecy cled product equivalent (C-class heavy oil)






Materials production Coal (Residue substitution) 3.1 MJ equivalent

Captive consumption: 0.171 kg

Captive consumption: 0.137 kg

Recycling system

Original system

Process (1)

Process (2)

Process (3)

Process (4)

Process (5)

Process (6)







0.041kg-CO2

0.022kg-CO2

0.0073kg-CO2

0.0025kg-CO2

0.0015kg-CO2

0.33kg-CO2

0.058kg-CO2

0.63kg-CO2

2.7 kg-CO2

0.29kg-CO2

0.069kg-CO2

2.7 kg-CO20.041

kg-CO20.022

kg-CO20.0073

kg-CO2

Recycling system

Original system

Bale input

Syngas production

Residue landfilling

Ammonia production

1 kg

0.03 kg


Plastic containers

and packaging

1 kg

Ammonia

Carbonic acid gas production

Slag

0.047 kg

0.877 kg

1.269Nm3

2.615Nm3

Bale input


1 kg

Resource extraction


Production


1 kg

Plastic containers

and packaging

0.877 kgUtility gas Ammonia production Ammonia

Carbonic acid gas production 0.559Nm3

Carbonic acid gas production 0.711Nm3

Resource extraction Processing Crushed stone, gravel 0.047 kg

Process (1) Process (2)

Process (3)Process (4)



Process (3) substitute (deficit)



0.041kg-CO2

0.022kg-CO2

0.0073kg-CO2

0.0015kg-CO2

0.82kg-CO2

2.7 kg-CO2

1.4kg-CO2

0.041kg-CO2

0.022kg-CO2

0.0073kg-CO2

2.7 kg-CO2

1.3 kg-CO2

1.4kg-CO2

0.0002kg-CO2

1.5 kg-CO2

120


Figure 6-21. Graphic representation of CO2 emissions and CO2 emissions reduction effect for gasification

(combustion)

Bale input

Syngas production

Residue landfilling

1 kg

0.03 kg


Plastic containers

and packaging

1 kg

Syngas volume

Bale input

Incineration, landfilling1 kg



1 kg

Plastic containers

and packaging

0.51L

Slag

0.00001 kg

19MJ

Purification, etc. C-class heavy oil

Resource extraction Processing Crushed stone, gravel 0.00001 kg

Recycling system

Original system

0.041kg-CO2

0.022kg-CO2

0.0073kg-CO2

0.0015kg-CO2

0.041kg-CO2

0.022kg-CO2

0.0073kg-CO2

2.7 kg-CO2

2.7 kg-CO20.15

kg-CO2

1.7 kg-CO2

0.00000005 kg-CO2


Process (3)




121


Figure 6-22. Graphic representation of CO2 emissions and CO2 emissions reduction effect for blast furnace

reduction (substitute for coke)



packaging

1 kg


particles

Residue processing(energy recovery)0.23 kg Coke ov en

Blast furnace


Iron ore

Coke

Hy drocarbon oil

Pig iron


Purification, etc.



Gas


Light oil component

Tar component

Oil coke0.619 kg

BTX separation


BTX separation


Purification, etc.

Coal resource ex traction Oil coke 0.014kg

0.77 kg

77.3 kg

447MJ

1.7 kg


Process (3)

Process (4)

Process (5)

Process (6)

Process (6) (deficit)

Process (4) (deficit)

0.041kg-CO2

0.022kg-CO2

0.0073kg-CO2

11.9 kg-CO2

0.12kg-CO2

0.051kg-CO2

0.053kg-CO2

Recycling system

All emissions from incineration of

generated products are added to the

blast furnace component.


Cement calcination

0.053 kg

0.13 kg 0.23 kg-CO2

0.10 kg-CO2

0.026 kg

0.04kg-CO2

Process (8)

Process (9)

Process (10)

Simple incinerationProcess (7)

0.015 kg


1 kg

Coke ov en Blast furnaceMaterials production

Iron ore

Coke

Gas

Pig ironRaw coal


Purification, etc.




input

Hy drocarbon oil


Light oil component

Tar component

Oil coke0.633 kg

BTX separation


77.3 kg

445MJ

1.74kg







Process (3), (5) substitute


2.7 kg-CO2

12.0kg-CO2

0.12 kg-CO2

0.10kg-CO2

Original system

All emissions from incineration of

generated products are added to the

blast furnace component.

0.07 kg-CO2

Coal0.05 kg

Resource extraction Materials production

Grid powerPurification, etc.Resourceextraction Power plant



Coal0.12 kg

Resource extraction Materials productionProcess (10) substitute

0.11 kg-CO2

0.29 kg-CO2

122


Figure 6-23. Graphic representation of CO2 emissions and CO2 emissions reduction effect for blast furnace

reduction (substitute for pulverized coal)



packaging

1 kg



particles

Energy recovery

0.23 kg

Blast furnace

Iron ore

Pig iron

Gas0.77 kg

77.3 kg

399MJ

General coal (pulv erized coal)



packaging1 kg



input

Purification, etc.





General coal (pulv erized coal)

Blast furnace

Iron ore

Pig iron

Gas

77.3 kg

396MJ9.28 kg

Original system

Recycling system0.041

kg-CO20.022

kg-CO20.0073

kg-CO2

0.041kg-CO2

0.022kg-CO2

0.0073kg-CO2

Process (1)


2.7 kg-CO2

Process (2)

Process (3)



Process (3) substitute (deficit) 0.24kg-CO2

23.0 kg-CO2

23.5 kg-CO2


RPF use

Cement calcination

0.053 kg

0.13 kg 0.23 kg-CO2

0.10 kg-CO2

0.026 kg

0.04kg-CO2

Process (6)

Process (7)

Simple incinerationProcess (4)

0.015 kg

0.07 kg-CO2Process (5)

Coal0.05 kg

Resource extraction


Grid powerPurification, etc.Resource extraction Power plant



Coal0.12 kg

Resource extraction


0.11 kg-CO2

0.29 kg-CO2

123


Figure 6-24. Graphic representation of CO2 emissions and CO2 emissions reduction effect for coke-oven

chemical material



packaging1 kg


particles

Residue landfilling

0.04 kg

Coke oven

Hydrocarbon oil

Coke


Gas


Light oil component

Tar component

BTX separation

0.92 kg

0.183 kg

0.366 kg

0.366 kg

C-class heavy oil0.104kg

Oil coke0.125 kg

Process (1)

0.041kg-CO2

0.022kg-CO2

0.0073kg-CO2

Process (2)

Process (3)

Process (4)

Process (5)

Process (6)

2.8 kg-CO2

0.032kg-CO2

Recycling system

Raw coal Coke ov en

Hy drocarbon oil

Coke

Gas

Benzene 0.0035 kgToluene 0.0010 kgXylene 0.0005 kg

Light oil component

Tar component

BTX separation

0.018 kg

0.053 kg

0.015 g


Oil coke0.006 kg




1 kgSimple incineration, residue landfilling

Collection, transport Baling Transport Bale input

Purification, etc.


C-class heavy oil0.0994L


BTX separation


Coal resource ex traction Oil coke 0.119 kgPurification,

etc.

Purification, etc.







Process (3), (5) substitute(deficit)



0.041kg-CO2

0.022kg-CO2

0.0073kg-CO2 2.7 kg-CO2

0.72 kg-CO2

1.9 kg-CO2

0.45 kg-CO2

0.52 kg-CO2

Original system

0.001kg-CO2

All emissions from coke production are

added to the incineration of

generated products component.

All emissions from coke production are

added to the incineration of

generated products component.

0.17 kg-CO2

124

Energy recovery

RPF use

RPF use (75% yield)

Figure 6-25. Graphic representation of CO2 emissions and CO2 emissions reduction effect for RPF use

(75% yield)

RPF use (89% yield)

Figure 6-26. Graphic representation of CO2 emissions and CO2 emissions reduction effect for RPF use

(89% yield)

1.14 kg＝3.0MJ



packaging1 kg


RPF production


0.23 kg

RPF 0.77 kg＝3.0MJ


1 kgSimple incineration,

landfillingCollection, transport Baling Transport Bale

input


etc.

Original system

Recycling system


0.041kg-CO2

0.022kg-CO2

0.0073kg-CO2

0.11kg-CO2

0.41kg-CO2

2.3 kg-CO2

0.041kg-CO2

0.022kg-CO2

0.0073kg-CO2 2.7 kg-CO2

2.8 kg-CO2



1.34 kg＝3.5MJ



packaging

1 kg


RPF production


0.09 kg

RPF 0.91 kg＝3.5MJ




input


etc.

Original system

Recycling system


0.041kg-CO2

0.022kg-CO2

0.0073kg-CO2

0.11kg-CO2

0.002kg-CO2

2.7 kg-CO2

0.041kg-CO2

0.022kg-CO2

0.0073kg-CO2 2.7 kg-CO2

3.3 kg-CO2



125

Cement calcination


Figure 6-27. Graphic representation of CO2 emissions and CO2 emissions reduction effect for cement

calcination (75% yield)


Figure 6-28. Graphic representation of CO2 emissions and CO2 emissions reduction effect for cement

calcination (89% yield)

1.17 kg＝3.0MJ



packaging1 kg




0.23 kg



1 kgSimple incineration,

landfillingCollection, transport Baling Transport Bale

input


etc.

Original system

Recycling system


0.041kg-CO2

0.022kg-CO2

0.0073kg-CO2

0.11kg-CO2

0.41kg-CO2

2.3 kg-CO2

0.041kg-CO2

0.022kg-CO2

0.0073kg-CO2 2.7 kg-CO2

2.9 kg-CO2



1.37 kg＝3.6MJ



packaging1 kg




0.09 kg





input


etc.

Original system

Recycling system


0.041kg-CO2

0.022kg-CO2

0.0073kg-CO2

0.11kg-CO2

0.002kg-CO2

2.7 kg-CO2

0.041kg-CO2

0.022kg-CO2

0.0073kg-CO2 2.7 kg-CO2

3.4kg-CO2



126



Figure 6-29. Graphic representation of CO2 emissions and CO2 emissions reduction effect for incineration

with power generation (12.81% efficiency)

Incineration with power generation (25% efficiency)

Figure 6-30. Graphic representation of CO2 emissions and CO2 emissions reduction effect for incineration

with power generation (25% efficiency)



1 kg


12.81%Power


0.031 kg1.27 kWh


1 kg



1.27 kWh

Resource extraction Power plant


Original system


kg-CO2

2.7 kg-CO2

2.7 kg-CO2Process (1) Process (2)


Process (2) substitute 0.73kg-CO2

0.001kg-CO2



1 kg


25%Power


0.031 kg2.47 kWh


1 kg



2.46 kWh

Resource extraction Power plant


Original system


kg-CO2

2.7 kg-CO2

2.7 kg-CO2Process (1) Process (2)


Process (2) substitute 1.4kg-CO2

0.001kg-CO2

127

Analysis

7.1 Proportion of environmental load reduction effect for processing of residues in recycling

through mechanical recycling methods

The manufacture of returnable pallet (substitute for new resin) through mechanical recycling produces

48% residues, which are processed through energy recovery methods (incineration with power generation,

RPF use, and cement calcination) based on a fixed ratio (Figure 3-5). In other words, the environmental

load reduction effect for returnable pallet (substitute for new resin) includes the effect from substituting the

production of pallet from new resin with the production of pallet from plastic containers and packaging,

and the effect from processing residues through energy recovery.

We therefore attempted to separately calculate the environmental load reduction effect from production of

pallet from plastic containers and packaging, and the reduction effect from the processing of residues

through energy recovery.

Environmental load reduction effect from the processing residues through energy recovery

Environmental load reduction effect for RPF use

We calculated the environmental load reduction effect from the processing of 1 kg of residues through

RPF use. First, we separately calculated the environmental load for landfilling of metal residues, and

combined with the environmental load reduction effects for all processing methods.


Table 7-1. Environmental load of recycling system for RPF use (mechanical recycling residue processing)


Table 7-2. Environmental load of original system for RPF use (mechanical recycling residue processing)



RPF production 1.36E+00 8.40E-02RPF incineration and use/ residue landfilling 2.64E+01 2.24E+00Simple incineration/residue landfilling of sorted residues 4.68E-01 2.74E-02Total 2.82E+01 2.35E+00



Collection, transport, and baling 1.26E+00 6.97E-02Bale simple incineration, residue landfilling 3.57E+01 2.71E+00Combustion of coal (RPF substitution effect) 2.69E+01 2.47E+00Total 6.39E+01 5.25E+00

128


Table 7-3. Environmental load reduction effect for RPF use (mechanical recycling residue processing)

Environmental load reduction effect for cement calcination


cement calcination.


Table 7-4. Environmental load of recycling system for cement calcination (mechanical recycling residue

processing)


Table 7-5. Environmental load of original system for cement calcination (mechanical recycling residue

processing)


Table 7-6. Environmental load reduction effect for cement calcination (mechanical recycling residue

processing)



Environmental load reduction effect (RPF use (MR residue processing)) 3.57E+01 2.90E+00



Cement raw fuel production 1.67E+00 1.03E-01Cement raw fuel incineration and use/residue landfilling 2.64E+01 2.24E+00Simple incineration/residue landfilling of sorted residues 4.68E-01 2.74E-02Total 2.85E+01 2.37E+00



Collection, transport, and baling 1.26E+00 6.97E-02Bale simple incineration, residue landfilling 3.57E+01 2.71E+00Combustion of coal (cement calcination substitution effect) 2.75E+01 2.52E+00Total 6.46E+01 5.31E+00



Environmental load reduction effect (cement calcination (MR residue processing)) 3.60E+01 2.94E+00

129

Environmental load reduction effect for incineration with power generation


incineration with power generation at a generation efficiency of 12.81%.


Table 7-7. Environmental load of recycling system for incineration with power generation (mechanical

recycling residue processing)


Table 7-8. Environmental load of original system for incineration with power generation (mechanical



Table 7-9. Environmental load reduction effect for incineration with power generation (mechanical


Environmental load reduction effect for energy recovery

We calculated the environmental load reduction effect from the processing of 0.48 kg of residues by

taking into account the processing ratio for mechanical recycling residues shown in Table 3-1 and the direct

landfilling of metals.

Table 7-10. Environmental load reduction effect for energy recovery from mechanical recycling residues



Incineration with power generation, residue landfilling 2.95E+01 2.48E+00Total 2.95E+01 2.48E+00



Collection, transport, and baling 1.26E+00 6.97E-02Bale simple incineration, residue landfilling 3.57E+01 2.71E+00Grid power (incineration with power generation substitution effect) 9.86E+00 5.97E-01

Total 4.69E+01 3.38E+00



Environmental load reduction effect (incineration with power generation (MR residue processing)) 1.74E+01 8.99E-01



Environmental load reduction effect (residue processing) 1.55E+01 1.20E+00

130

Proportion of environmental load reduction effect for processing of residues in recycling

through mechanical recycling methods

The environmental load reduction effect for production of pallet from plastic containers and packaging

was calculated by subtracting the reduction effect for the processing of residues through energy recovery

obtained in (1) from the reduction effect for mechanical recycling (substitute for new resin) in Section 5.1.2.

Likewise, the ratio of both effects was also calculated for mechanical recycling (substitute for new resin) as

a whole.

Table 7-11. Environmental load reduction effects for production of pallet from plastic containers and

packaging and residue energy recovery and their ratios

The above results show that, in mechanical recycling (substitute for new resin), the environmental load

reduction effect for the processing of residues through energy recovery is larger than that for the production

of pallet. It must be noted, however, that pallet produced from plastic containers and packaging as well as

those made from new resin can be recycled after their use, resulting in additional environmental load

reduction effect, which was not taken into consideration in this study.



Ratio of the Environmental load reduction effect

Environmental load reduction effect for returnable pallet (new resin substitute) (total) 2.76E+01 1.65E+00 ーEnvironmental load reduction effect for residue energy recovery 1.55E+01 1.20E+00 73%

Environmental load reduction effect for returnable pallet production 1.21E+01 4.22E-01 27%

131

7.2 Analysis of environmental load reduction effect due to differences in bale composition

We also determined the impact of the differences in bale composition on yield and environmental load

reduction effect.

Targets of evaluation

Analysis was conducted based on two cases; namely, returnable pallet (substitute for new resin,

substitution ratio for simple average case) and incineration with power generation (12.81% generation

efficiency). Feedstock recycling was not included in this evaluation because there was no correlation

between bale composition and production volume (based on 2007 JCPRA Report).

Bale composition

Since the 2007 JCPRA Report indicated a variation in mechanical recycling rate ranging from 45% to

60% among recyclers in regard to bale composition, we changed the composition ratio in order to achieve

recycled product yields ranging from 45% to 60%, based on the composition ratio of recycled products and

residues assumed for the base case in mechanical recycling.

Accordingly, the bale composition in order to achieve yields of 45% and 60% are as shown below. (The

yield for the base case used in computations in previous sections is 51%).

Table 7-12. Bale composition ratio for each case


45% yield case 22.9% 25.5% 21.7% 16.7% 1.0% 4.2% 8.0% 100.0%

60% yield case 28.2% 31.4% 18.4% 12.0% 0.8% 3.0% 6.2% 100.0%

Base case 25.0% 27.8% 20.4% 14.8% 0.9% 3.7% 7.3% 100.0%

Returnable pallet (substitute for new resin)

Composition settings

The composition ratio of recycled products and residues for the two cases are as shown below.

Table 7-13. Composition ratio of recycled products and residues for the 45% yield case


Recycled products 19.2% 21.3% 4.6% 0.0% 0.0% 0.0% 0.8% 45.8%

Residues 3.7% 4.2% 17.2% 16.7% 1.0% 4.2% 7.2% 54.2%

Total 22.9% 25.5% 21.7% 16.7% 1.0% 4.2% 8.0% 100.0%

Table 7-14. Composition ratio of recycled products and residues for the 60% yield case


Recycled products 25.5% 28.4% 6.1% 0.0% 0.0% 0.0% 1.0% 61.0%

Residues 2.7% 3.0% 12.3% 12.0% 0.8% 3.0% 5.2% 39.0%

Total 28.2% 31.4% 18.4% 12.0% 0.8% 3.0% 6.2% 100.0%

132

Environmental load reduction effect (45% yield case)


Table 7-15. Environmental load of recycling system for returnable pallet (substitute for new resin, simple

average substitution ratio, 45% yield case)


Table 7-16. Environmental load of original system for returnable pallet (substitute for new resin, simple



Table 7-17. Environmental load reduction effect for returnable pallet (substitute for new resin, simple




Table 7-18. Environmental load of recycling system for returnable pallet (substitute for new resin, simple









Total 5.76E+01 3.76E+00



Environmental load reduction effect for returnable pallet (new resin substitute) 2.65E+01 1.65E+00




133


Table 7-19. Environmental load of original system for returnable pallet (substitute for new resin, simple



Table 7-20. Environmental load reduction effect for returnable pallet (substitute for new resin, simple






efficiency, 45% yield case)


Table 7-22. Environmental load of original system for incineration with power generation (12.81%






Total 6.73E+01 4.23E+00



Environmental load reduction effect for returnable pallet (new resin substitute) 2.94E+01 1.64E+00





Total 3.47E+01 2.66E+00





Grid power 1.17E+01 7.06E-01

Total 4.65E+01 3.37E+00

134


Table 7-23. Environmental load reduction effect for incineration with power generation (12.81% efficiency,

45% yield case)






Table 7-25. Environmental load of original system for incineration with power generation (12.81%



Table 7-26. Environmental load reduction effect for incineration with power generation (12.81% efficiency,

60% yield case)



Reduction effect（Incineration with power generation） 1.18E+01 7.13E-01





Total 3.73E+01 2.79E+00





Grid power 1.25E+01 7.59E-01

Total 4.99E+01 3.56E+00



Reduction effect（Incineration with power generation） 1.26E+01 7.66E-01

135

Summary of analysis of environmental load reduction effects due to differences in bale

composition

This section summarizes results from (3) and (4) into graphs.

Figure 7-1. CO2 emissions and energy resource consumption reduction effects due to changes in bale

composition

Variations in yield only had negligible impact on CO2 emissions reduction effect for returnable pallet

(substitute for new resin). This can be attributed to the negation of effects between the increase in pallet

substitution effect due to the increase in yield and the decrease in substitution effect from energy recovery

of residues due to the decrease in residues.

For incineration with power generation, variations in the PE/PP ratio in the bale in accordance with the

yield also resulted in variations in the amount of generated power, resulting in minimal impact despite of

some variations in the environmental load reduction effect.

136

These results indicate that variations in bale composition do not significantly influence the environmental

load reduction effects for mechanical recycling and incineration with power generation. Although the

evaluation was conducted only for one case, namely for the latest bale composition, the results can still be

considered valid since the impact of the composition is minimal.

Moreover, results of Section 5.1 and Section 5.3.3. show that for mechanical recycling, environmental

load reduction effect is influenced by substitution ratio and substituting materials, while for incineration

with power generation, it is influenced by power generation efficiency. Going forward, it will be necessary

to improve the major parameters for these factors in order to enhance the environmental load reduction

effects of the different processing methods.

137

Summary

Summary of evaluation procedures conducted

In this study, we conducted evaluation by LCA to analyze the environmental load reduction effect ((1)

CO2 emissions reduction and (2) energy resource consumption reduction) of recycling methods

(mechanical recycling and feedstock recycling) and energy recovery using plastic containers and packaging,

the main example of mixed plastics, as the standard input material. Evaluation procedures and analysis of

results were discussed through a Working Group.

The evaluation in this report was carried out in reference to the system boundary, substitutes, and

inventory data presented in the Report on the Study of Environment Load of Plastic Containers and

Packaging Recycling Methods conducted by the Japan Containers and Packaging Recycling Association

(JCPRA) in June 2007, except for the following revisions:

1. Expansion of system boundary by setting the discharge of plastic containers and packaging from

homes as the start point

2. Inclusion of incineration with power generation (waste-to-energy power generation) in the

processing methods targeted for evaluation, revision of power generation efficiency, and addition

of discussion on future potential

3. Revision of pallet weight and substitution ratio for returnable pallet (substitute for new resin)

under mechanical recycling

4. Update of plastic containers and packaging composition to the latest data (from Isesaki City)

5. Revision of mechanical recycling methods and blast furnace reduction method for feedstock

recycling based on the latest methods for using residues

6. Use of IDEA V.2.2 in regard to the primary unit database

138

Summary of LCA analysis results

CO2 emissions and energy resource consumption reduction effects for the processing of 1 kg of plastic

containers and packaging using different methods are as shown below.

Figure 8-1. CO2 emissions and energy resource consumption reduction effects for each processing method

(MR: mechanical recycling, FR: feedstock recycling, ER: energy recovery)

139

For some of the processing methods evaluated, parameters were changed as shown below based on

previous calculation results:

Returnable pallet (substitute for new resin): Substitution ratio was changed to include from

minimum to maximum ratios, with the simple average substitution ratio used as the base case

RFP use: Yield was varied from 75% to 89%, with the average between 75% and 89% used as the

base case

Cement calcination: Yield was varied from 75% to 89%, with the average between 75% and 89%

used as the base case

Incineration with power generation: Power generation efficiency of 25% was also plotted, with

12.81% used as the base case

Discussion

Evaluation by LCA of environmental load of different methods for processing of plastic containers

and packaging discharged from homes enabled the calculation of the environmental load reduction

effects for energy recovery, mechanical recycling, and feedstock recycling methods.

Energy recovery

The evaluation targeted three types of energy recovery methods: RPF use, cement calcination, and


RPF use

RPF use is a highly versatile method for processing plastic waste into pellet form and is used

mainly as substitute for coal in boilers, etc. RPF use showed a high CO2 emissions reduction

effect ranging from 2.7 to 3.2 kg-CO2, which is comparable to that of feedstock recycling blast

furnace reduction method and approaches that of coke-oven chemical material method.

Cement calcination

Cement calcination is a method for using plastic waste as substitute for coal, as fuel inputted into

cement kilns in the cement manufacturing process. Cement calcination showed a high CO2

emissions reduction effect ranging from 2.8 to 3.3 kg-CO2, which is comparable to that of RPF

use.


The incineration-with-power-generation method evaluated here covered plastic waste included

among combustible waste discharged from homes. Incineration with power generation at an

efficiency of 12.81%, which is the average level for Japan, exhibited a CO2 emissions reduction

effect of 0.7 kg-CO2, one of the lowest among the methods evaluated. Highly efficient

incineration-with-power-generation facilities in Japan operate at a generation efficiency of 25%.

But even at this high efficiency level, the CO2 emissions reduction effect was only 1.4 kg-CO2,

the same level as that of feedstock recycling and mechanical recycling methods, which do not

have a high CO2 emissions reduction effect. Unlike RPF use and cement calcination, which have

high energy utilization efficiency, incineration with power generation (of combustible waste) has

low power generation efficiency. Moreover, while RPF use and cement calcination serve as coal

140

substitute, incineration with power generation (of combustible waste) serves as grid power

substitute. These two factors lower its CO2 emissions reduction effect. It remains a fact, however,

that incineration is indispensible as a method for processing plastic waste that is difficult to

separate from food residues. (Landfilling is difficult to carry out in Japan due to its limited land

area and for sanitary reasons.) Results of the evaluation showed that processing plastic waste

through incineration with power generation enables a certain level of CO2 emissions reduction

effect.

In addition, efforts are underway in Japan to increase the efficiency of power generation through

incineration of combustible waste. Incineration-with-power-generation facilities outside Japan

have higher efficiencies and even adopt co-generation measures. Going forward, we expect to see

the implementation of initiatives that will further improve the efficiency of Japan’s

incineration-with-power-generation facilities in order to achieve load reduction effects comparable

to those of other methods.


For mechanical recycling methods, we evaluated returnable pallets, which have the best track

record in processing of plastic containers and packaging.

Results showed that the material of the product to be substituted and the substitution ratio of

virgin resin with plastic containers and packaging are important factors affecting the CO2

emissions reduction effect in mechanical recycling.

Approximately half of the raw material inputs for mechanical recycling are turned into residues,

which are subjected to energy recovery processing. The environmental load reduction effect

computed in this study includes the reduction effect from production of pallet, approximately

half of which is made up of raw materials, and the reduction effect from energy recovery of the

other half made of residues.

Between the two components, the reduction effect for energy recovery of residues was larger

compared to that for the production of pallet.

Feedstock recycling

The targets of evaluation for feedstock recycling were coke-oven chemical material, blast furnace

reduction, gasification, and liquefaction.


Coke-oven chemical material is a method for using plastic waste as substitute for coal inputted

into coke ovens in the iron manufacturing process. This method showed the highest CO2

emissions reduction effect among all the processing methods at 3.2 kg-CO2.

The reasons for the large reduction effect are: (1) use of plastic waste as substitute for coal

inputted into coke oven results in removal of the CO2 emissions component attributed to coal, (2)

generation of hydrocarbon oil as by-product that serves as substitute for heavy oil results in

removal of the CO2 emissions component attributed to heavy oil, and (3) high product yield of

141

89%.



Blast furnace reduction (substitute for coke) showed a high CO2 emissions reduction effect

at 3.2 kg-CO2, which is equal to that of coke-oven chemical material.

The reason for the large reduction effect lies in its use in the pig iron production process.

Substitution of coke conventionally used as reducing agent in this process results in removal

of the CO2 emissions component attributed to coke, which emits a high amount of CO2

compared to other fossil fuels.


Blast furnace reduction (substitute for pulverized coal) is a method for using plastic waste as

substitute for pulverized coal inputted into blast furnaces in the iron manufacturing process.

Although blast furnace reduction (substitute for pulverized coal) showed a somewhat lower

CO2 emissions reduction effect at 2.5 kg-CO2, this was still high compared to other

processing methods. Since pulverized coal has lower calorific value than coke and does not

generate by-products, the reduction effect was lower compared to substitution of coke.

Gasification

Gasification is a method for thermal decomposition of plastic waste in high temperature to

obtain gaseous products (hydrogen, carbon monoxide). Gas products are used either by

gasification for ammonia production or gasification for combustion.


The CO2 emissions reduction effect for gasification (ammonia production) was 2.1 kg-CO2,

which was intermediate compared to other methods. In this method, gas generated from

thermal decomposition of plastic waste is used instead of purified gas (from natural gas),

which is the raw material for ammonia production. The reduction effect is due to the

removal of the emissions component attributed to carbonic acid gas, which is a by-product

of ammonia production from purified gas (from natural gas).

One reason for the lower reduction effect compared to blast furnace reduction and

coke-oven reduction used as substitute for coal is that the method is used as a substitute for

purified gas produced from natural gas.


The CO2 emissions reduction effect for gasification (combustion) was 1.6 kg-CO2, which

was intermediate compared to other methods. As a substitute for heavy oil used as fuel, its

reduction effect is lower compared to when used as substitute for products such as ammonia,

which are produced through chemical processes.

Liquefaction

Liquefaction is a method for thermal decomposition of plastic waste in high temperature to

obtain oily products (light oil, medium gravity oil, and heavy oil). Unlike gasification,

where thermal decomposition is carried out at high temperatures above 1000ºC, liquefaction

142

is carried out at around 400 to 500ºC. Products of liquefaction, aside from being used as fuel,

have been investigated for use as chemical raw material substitute for naphtha. In this study,

liquefaction was evaluated in terms of its use as fuel.

The CO2 emissions reduction effect for liquefaction was 1.4 kg-CO2, which was

intermediate compared to other methods. Data used for evaluation, however, were from a

plant in Hokkaido, which is a cold weather region, giving rise to the possibility that the

effect was lower due to significant energy loss in the plant.

In summary, these results show that energy recovery having a certain level of efficiency is not inferior to

mechanical recycling and feedstock recycling in terms of environmental load reduction effect.

Further, environmental load reduction effects for energy resource consumption were generally similar to

those for CO2 emissions. However, when substituted products have high carbon content in relation to the

calorific value upon combustion, such as coal, petroleum, etc., the CO2 emissions reduction effect tends to

be larger compared to that for energy resource consumption. On the other hand, for those with low carbon

content in relation to the calorific value upon combustion, such as natural gas, the CO2 emissions reduction

effect tends to be smaller compared to that for energy resource consumption.

143

Future issues

・ As the recycling of plastic resources continues to progress, the environment load reduction effect of

individual methods for effectively using plastic waste should be compared and evaluated as needed

by Life Cycle Assessment (LCA) as a matter of policy.

・ Plastic-related inventory data must be continuously updated, and the accuracy of evaluations by LCA

should be improved.

・ The technical aspects of evaluations by LCA and the level of recycling plastic resources in Japan

should be improved by disseminating information overseas and exchanging opinions with overseas

counterparts.

evaluation of environmental load reduction effect of ... · selective collection) include glass...

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