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Disseminated Document

A Study on Energy Efficiency Index in

Petrochemical Industry

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A St d E Effi i I d i

Disseminated Document

A Study on Energy Efficiency Index in


Department of Alternative Energy Development and Efficiency (DEDE)

A Study on Energy Efficiency Index in Petrochemical Industry

Petrochemical Industry is one of the most important primary industries to

Thailand’s economic development. It is the foundation of wide variety of industrial production

processes such as plastic and container industry, textile industry, rubber industry, agricultural

and fertilizer industry. These industries help create tremendous value added to Thailand

exporting sector. In 2006, the exporting values of upstream, intermediate and downstream

petrochemical products are 27,694, 41,729 and 15,1468 million Baht, respectively. In addition,

the country also saves millions of bath per year on importing goods. The utilization of natural

gas in the process is also a right direction on increase the value of locally available raw material

which, in turn, benefit to Thai’s economy and society as a whole. Continued expansion of this

industrial sector is foreseeable in the future.

Production process of petrochemical industry is considered one of the most energy

intensive operations. Due to increase energy consumption trend of this industry and to correctly

accommodate the future economic expansion, it is important to facilitate this industry to

efficient energy management initiatives in order to optimize the whole process while maximize

the benefit. In addition to the gain from energy conservation and higher energy efficiency, this

will enhance the capability of the industry to compete on the global scale. From these reasons,

the Department of Alternative Energy Development and Efficiency (DEDE), a responsible governmental body who oversee the industrial energy management, considers this important

strategy and duty to promote the increase in energy efficiency of petrochemical industry. The

activities will be carried out under the Energy Conservation and Promotion Acts of 1992.

One strategy which the Department of Alternative Energy Development and Efficiency has been executed to urge the industry about the energy efficiency is the analysis of energy

usage per production unit (Energy Index, EI). Hence it is DEDE’s initiative to develop Energy

Consumption of Petrochemical Industry in Thailand project to use the energy consumption

data of this industry as a step to develop energy benchmarking standard. Moreover, the

acquired information may be evaluated for preparation of energy efficiency index and energy

conservation of each manufacturer. Finally, the outcome of this project may lead to the right

direction on defining the appropriate future plan for energy conservation plan of petrochemical

industry.

This report is to distribute the result of this project which includes the analysis of energy consumption index of petrochemical industry, approach on promotional plan for energy

conservation, and techniques for efficient energy usages. Authors hope that this report will

further be more or less useful to stake holders and any involved parties.

PREFACE



CONTENT

PREFACE

CHAPTER 1 : OVERVIEW OF THAILAND PETROCHEMICAL INDUSTRY 1

1.1 The Petrochemical Industry Structure 1

1.2 Types of Petrochemical Industry 4

1.3 Petrochemical Feedstock 6

1.4 How Petrochemical Industry Affects Economic System 7

1.5 Energy Consumption of Petrochemical Industry in Thailand 12

CHAPTER 2 : ENERGY CLASSIFICATION OF PETROCHEMICAL INDUSTRY 14

2.1 Classification of Petrochemical Industry 14

2.2 Production Processes 15

CHAPTER 3 : ENERGY CONSUMPTION IN PETROCHEMICAL INDUSTRY 22

3.1 Energy Consumption Index 22

3.2 Specific Energy Consumption (SEC) 23

3.3 Evaluation of Energy Intensity (EI) 29

CHAPTER 4 : THE PROMOTION OF ENERGY CONSERVATION 31

4.1 Problems in Petrochemical Industry 31

4.2 SWOT Analysis 32

4.3 Promotional Plan for Energy Conservation In The Petrochemical 33

CHAPTER5 : TECHNOLOGY AND MEASURES FOR ENERGY CONSERVATION IN PETROCHEMICAL INDUSTRY

36

5.1 Development and Improvement of Production Technology 36

5.2 Energy Efficiency Improvement for Processes and Equipments 40

SUMMARY 48

REFERENCES 50

LIST OF ABBREVIATION 52

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1



2

In general, the petrochemical industry uses raw materials from the petroleum industry

to manufacture products such as plastic resins, synthetic fibers, synthetic rubbers, surface

coating materials and various types of adhesives. These products are considered primary raw

materials for human beings’ basic consumption items, occupational tools and equipment, and

various amenities for mankind. Figure 2 shows the links between the petroleum industry and

petrochemical industry; Figure 3 shows the structure of Thailand’s petrochemical industry.

Figure 2 Thailand petroleum and petrochemical network

Soource: PTIT, 20

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4

1.2 Types of Petrochemical Industry

The petrochemical industry is classified into 3 main groups, on the basis of their

products (as shown in Figure 4).

Upstream Petrochemical Industry

Intermediate Petrochemical Industry

Downstream Petrochemical Industry

Figure 4 Overview of Thailand petrochemical industry

1.2.1 Upstream Petrochemical Industry

Upstream petrochemical industry is the production of petrochemical products which are

feedstock for further production of other petrochemical products (intermediate and

downstream). It consists of 7 kinds of products, or “the Seven Sisters”, which are divided into

the following 3 groups on the basis of their molecular structure:

Alkane group, which is methane‐based

Olefin group, which is ethylene‐based, propylene‐based and Mixed C4‐based

Aromatic group, which is benzene‐based, toluene‐based and xylene‐based

Supporting: Infrastructure, Logistic, HR, Finance, Rules& Regulations

Value chain component

Key activities • E&P

• Oil Refinery

• Gas separation

• Olefins

- Ethylene - Propylene

• Aromatics

- Benzene

- Para-Xylene

• Plastic Resins Commodity (PE, PP, PVC, PS, EPS,

PET) Engineering (PC, POM, PBT*, Nylon

6,6*, PMMA) Synthetic Fibre - Polyester - Nylon 6 - Polypropylene - Acrylic Syn. Rubber/ Elastomers

- BR, SBR, EPDM* Syn. Coating/ Adhesives - PVA*, Silicone

• Compounding

• Olefins - EDC/VCM - EO**/EG** - Oxo Alcohol* - Acrylonitrile* • Aromatics - Ethylbenzene** - Styrene - Cyclohexane** - Caprolactam - Cumene/Phenol** - PTA -PA

Conversion Industries

Downstream

Intermediate

Upstream

Oil & Gas

Note: * No local production, ** Investment in progress



5

1.2.2 Intermediate Petrochemical Industry

Intermediate petrochemical industry uses upstream petrochemical products as feedstock

and supplies to downstream petrochemical industry. Its products are grouped on the basis of

their upstream petrochemicals, as follows:

Alkane Intermediates, namely, products from upstream methane, such as methanol or methyl alcohol, formaldehyde, ammonia, phosgene, etc.

Olefin Intermediates, namely, ethylene products such as ethylene dichloride, (EDC), vinyl chloride monomer (VCM), ethylene oxide (EO), and ethylene glycol (EG), propylene products such as oxo alcohol and acrylonitrile

Aromatic Intermediates, namely, benzene products such as ethyl benzene (EB), styrene monomer(SM), cyclohexane, carprolactam, and paraxylene products, etc.

1.2.3 Downstream Petrochemical Industry

Downstream petrochemical Industry uses upstream or intermediate petrochemical

products as feedstock to manufacture downstream products or end products prior to conversion

in other industries. They are categorized by end product, as follows:

Plastic resins Synthetic Fibers Synthetic rubbers Synthetic coating and Adhesive materials

ดิบสําหรับการผลิตอุตสาหกรรมปโตรเคมี



6

1.3 Petrochemical Feedstock

There are 2 types of feedstock for the petrochemical industry: natural gas and naphtha.

The selection of feedstock varies on the advantages and disadvantages in the access to the

feedstock, and therefore varies from one country to another. For instance, in countries like the

USA, Canada, and the Middle East, production of petrochemicals is from natural gas, whereas in

Japan, Korea, Singapore, and Europe, which do not have natural gas, naphtha is used instead,

since it is sold in the world market and is easy to transport. In the case of Thailand, both are

used. The type of feedstock also determines the manufacturing process used by manufacturing

plants. Figure 5 shows feedstock sources for the industry.

Figure 5 Petrochemical feedstock

Gas separation Wet gas

Refinery

Crude oil

Condensate Splitter

Condensate

Petrochemical Feedstock

Refined products



• Methane • Ethane • Propane‐Butane (LPG) • NGL

• LPG • Naphtha‐Gasoline • Gas Oil – Kerosene,

Jet, Diesel • Fuel Oil • Bitumen • Etc.

• LPG• Naphtha • Gas Oil

• LPG• Naphtha

Dry gas

Residue



7

1.4 How Petrochemical Industry Affects Economic System

1.4.1 The Role of Petrochemical Industry in Thailand

The petrochemical industry brings in tremendous, uninterrupted revenue to the country

as show in Table 1. In year 2006, total revenue from petrochemical industry exceed 447.760

million Baht which is equivalent to 6‐percent of gross domestic product (GDP). Moreover, the

industry also generates important raw materials for several downstream industries such as

automachine, electrical and electronics, cosmetics, agricultural, packaging and textile industries.

The petrochemical industry has a significant effect on the development of the country

directly and indirectly. Not only does it add value to oil and natural gas, but it is also related to

numerous other industries as shown in Figure 6, for example, packaging, spare parts, electronic

parts, textile, construction, etc

Table 1 Values of Thailand’s petrochemical production

Source : PTIT Focus, 2005

.

6.0%6.1%5.9%4.9%4.4%Compare to GDP

2.2%2.2%2.6%2.6%2.8%2.8%2.4%2.4%2.3%2.3%Compare to GDPCompare to GDP

160,257181,427182,829143,812128,458•Value Added of Petrochem. Ind.: Exclude Import and Feedstocks

(MM Baht)

3.5%3.7%3.8%3.2%2.8%Compare to GDP

260,714264,231244,486188,578153,202•Net Revenue: Exclude Import Portion (MM Baht)

447,760432,645382,500290,150239,060• Total Revenue (MM Baht)

Petrochemical Status

7,423,918 7,104,2286,503,4885,928,9755,450,643GDP: Current Price (MM Baht)

25492548254725462545

6.0%6.1%5.9%4.9%4.4%Compare to GDP

2.2%2.2%2.6%2.6%2.8%2.8%2.4%2.4%2.3%2.3%Compare to GDPCompare to GDP

160,257181,427182,829143,812128,458•Value Added of Petrochem. Ind.: Exclude Import and Feedstocks

(MM Baht)

3.5%3.7%3.8%3.2%2.8%Compare to GDP

260,714264,231244,486188,578153,202•Net Revenue: Exclude Import Portion (MM Baht)

447,760432,645382,500290,150239,060• Total Revenue (MM Baht)

Petrochemical Status

7,423,918 7,104,2286,503,4885,928,9755,450,643GDP: Current Price (MM Baht)

25492548254725462545

Note: B.E. 2549 estimate GDP growth 4.5%, FX = 38 Bath/$

2002 2003 2004 2005 2006

2006



8


Figure 6 Downstream petrochemical production values

In addition to producing ample supplies for domestic demand, in 2005 the

petrochemical industry had more than 200,000 million Baht worth of surplus output for export,

or 4.85 percent of the country’s export value.



9


Figure 7 values generated by natural gas year 2005

Figure 7 shows that the petrochemical industry, which uses only 11.3 percent of natural

gas, generates as much revenue as 158,277 million Baht., whereas electricity industry, which

uses 79.6 percent of natural gas, generates 197,899 million Baht. In other words, revenue from

petrochemical industry is approximately 80 percent that of electricity generation, but

petrochemical industry uses only 14 percent of the volume of natural gas used in generating

electricity. This is the reason why Thailand must conduct a serious study and continue to

develop petrochemical products.

Values Generated by Natural Gas – B.E. 2548

Incremental values forgone if indigenous gas not used,and import fuel instead

Incremental values forgone if indigenous gas not used,and import fuel instead

414,

828

66,4

0018

3 ,6 7

6

Value lostif import fuels

(194,899 - 183,676 = 11,223electricity - imported fuel = value added)

Value lostif import fuels

(194,899 - 183,676 = 11,223electricity - imported fuel = value added)

Gas Used

790,080

MMSCF

(excl. LPG for feedstock)

Unit: Million Baht

• Industry Value– Electricity– E&P– Petrochemical

–LPG

Gas Prod.

835,743

MMSCF

79.6%100.0%

11.3%

9.1%

Direct

Financial

Benefit

Economic

Multiplier

194,899230,749

- 100,576(NG)

- 57,701 (Condensate)

25,802

• Government Take– Income Tax - E&P 36,957– Royalty - E&P 29,443

*

158,277

Values Generated by Natural Gas Year 2005



10

1.4.2 Petrochemical Production

1) Production

• Production Capacity

In 2006 production capacity of Thailand’s petrochemical industry was

19,000,000 tons, comprising 6.5 million tons upstream products, 4.5 million tons of intermediate

products, and 8.0 million tons of downstream products, as shown in Figure 8. It can be seen that

the industry has continuously expanded from year 2002 onward, with a total of 4.0 million tons

growth between years 2002 and 2006.

Figure 8 Thailand petrochemical production capacity

• Production and Production Rate

Thailand produced nearly 16,000,000 tons of petrochemical products in 2005

and was then expecting more than 16,000,000 tons for 2006 (Figure 9). In downstream

industries, the production increased highest from years 2005 due to the new downstream plants

have been started to produce in various petrochemical substance for example cyclohexane and

PTA. The Intermediate products also illustrated an increase, while upstream products decreased

due to halt in operation for the purpose of maintenance and repair.

B.E.2549 is est imation data

2545 2546 2547 2548 25492002 2003 2004 2005 2006



11

N.B. Years 2006 approximated values.

Figure 9 Production volume of petrochemical products from years 2002 to 2006 (PTIT)

Table 2 Average operation capacity of Thailand‘s petrochemical industry from years 2003‐2006

Petrochemical

Industry

Capacity Average (%)

2002 2003 2004 2005 2006

Upstream 89 99 98 94 90

Intermediate 85 98 100 90 81

Downstream 86 87 88 86 85

Source: PTIT, 2006

Upstream and intermediate petrochemical production had an average of 90‐95 percent,

while downstream production had 85 percent of production capacity. In 2006 downstream

production slightly decrease as newly set‐up facilities were not operating in full yet.

Analyses of recent periods have found that production and marketing have been

growing satisfactorily, and will continue to rise. The liberalization of petrochemical trade during

the past decade plus the country’s managing to sail through the 1997 economic crisis have

helped strengthened the Thai entrepreneurs, who saw the need to unite to increase their

business potential. Markets have expanded noticeably, both domestically and abroad.

Thailand Petrochemical Production

02,0004,0006,0008,000

10,00012,00014,00016,00018,000

2545 2546 2547 2548 2549

KTA

Upstream Intermediate Downstream

2002 2003 2004 2005 2006



12

1.5 Energy Consumption of Petrochemical Industry in Thailand

The petrochemical industry relies heavily on energy. With its present growth rate, and

as companies are also constantly trying to expand their production, consumption of electricity,

gas and fuels will increase unavoidably, no matter how much emphasis is given to energy

conservation.

1.5.1 Energy consumption

From the data compiled from 30 plants producing upstream, intermediate and

downstream petrochemicals, the study has found that consumption of energy is highest in the

upstream industry, (data from all the plants in Thailand) as shown in Table 3

Table 3 Energy consumption in Thailand’s petrochemical industry


Audited Plants (%)

Energy Use (Ktoe)

Year 2005 (%) Year 2006 (%)

Upstream 100 2,172 68.91 2,186 64.48

Intermediate 43 213 6.76 475 14.01

Downstream 32 768 24.33 729 21.50

Total 3,152 100.00 3,390 100.00

However, energy consumption of the country’s entire industrial sector, including food,

drinks, textiles, wood, chemicals, paper, ceramic, cement and metal (referred from energy

consumption data from DEDE’s energy consumption annual report), was selected to compare

the energy used in the petrochemical industry. It was found that the petrochemical sector

consumes 15 to 17 percent of the total industrial sector’s consumption.



13

Electricity6%

Steam38%

Natural Gas42%

LPG 0.6%

Diesel0.6%

Fuel Oil1.7% Others

11.1%

1.5.2 Proportion of Energy Consumption in Petrochemical Industry

Consumption data compiled from selected manufacturing plants in 2006 shows the main

energies used in the manufacturing process of products consists of electricity, steam, natural gas

(NG), liquid petroleum gas (LPG), diesel oil, fuel oil, and others (process off‐gas, fuel gas, etc.) as

shown in Table 4 and illustrated in Figure 10

Table 4 Proportion of Energy Consumption (%)

Energy Type Ratio (%)**

Natural Gas 42.0

Steam 38.0

Electricity 6.0

Fuel oil 1.7

Diesel oil 0.6

LPG 0.6

Others (Process off‐gas, Fuel gas, etc.) 11.1

Total 100

**estimation value from participating petrochemical plant

Figure 10 Proportion of energy consumption in years 2006

As shown above, natural gas is the topmost energy being used in petrochemical

production (mostly as direct fuel for the oven, or direct heat), while stream is second in quantity.

Other types of energy, also estimated from consumption in the production process, are used at

smaller quantities.



14

2.1 Classification of Petrochemical Industry

The petrochemical industry covers a vast array of products, and the manufacturing

processes vary from one product to another. Sometimes the same products use different in raw

materials, technological processes, and even different equipment. For this reason, energy is

used in varying amounts.

However, from this study, in which consumption of energy is compared using

international basis, the industry is classified on the basis of production process, with the aim to

present an analysis of indices of energy consumption which are correct, suitable and beneficial

but without harming the existing plants from where data were given. The study result will reveal

overall facts and figures of each group as a whole, and not of individual products. This is

because there are not too many petrochemical plants in Thailand, and presenting too detailed

data may be revealing confidential information of the businesses.

Therefore, petrochemical industry were divided into 3 groups as follows:

Upstream Petrochemical Industry)

- Olefins Group

- Aromatics Group

Intermediate Petrochemical Industry

Downstream Petrochemical Industry

- HDPE

- PS, PP, EPS

- Emulsion PVC, ABS, SAN, PC

2.CLASSIFICATION OF PETROCHEMICAL INDUSTRY



15

1) Cracking Process Cracking is a process in which molecules of raw material are dissociated into smaller

ones. There are two types of cracking process, thermal steam cracking and catalytic cracking.

2.2 Production Processes

2.2.1 Upstream Petrochemical Production

Upstream petrochemical industrial process aims at producing primary feedstock for the

next group of products. Its production process is shown in Figure 11‐13 (source: PTIT 2006), with

7 major products, namely, methane, ethylene, propylene, Mix C4 benzene, toluene and xylene as

the basic chemicals for further petrochemical development. There are 2 major processes, as

follows:

Thermal Steam Cracking

Steam cracking is the dissociation of raw material such as ethane and propane yielding important petrochemical products, ethylene and propylene, mixed C4, pyrolysis gasoline. Methane and hydrogen are also some of major by‐products.

Catalytic Cracking

Dissociation of larger, stable molecules requires catalysis. Refinery products such as gasoil and fuel oil may be passed through catalytic cracker to obtain gasoline and diesel as major products and by‐product, propylene, which is primary petrochemical product.

2) Reforming Process

Reforming of hydrocarbon structure may be accomplished by the use of heat,

pressure and/or catalyst in order to obtain desired products. This process converts heavy

naphtha to aromatics such as benzene, toluene and xylene as well as hydrogen as by‐product.

Reforming may be carried out by several following methods.

Dehydrogenation is a process in which hydrogen atoms are being taken away from saturated hydrocarbons structure leaving product of unsaturated hydrocarbons such as the dehydrogenation of cyclohexane to aromatics.

Dehydrocyclization is a process in which hydrogen atoms are being taken away from aliphatic hydrocarbons yielding aromatics such as dehydrocyclization of paraffin.

Dealkylation is the extraction of alkyl group from toluene and xylene yielding benzene.

Transalkylation or Disproportionation is the combination process of two molecules resulting in two new molecules which are bigger and smaller than precursor ones i.e., catalytic transalkylation of toluene to benzene and xylene.

Isomerization involves the molecular restructuring of material while retaining the same number of atoms i.e., isomerization of o‐xylene and m‐xylene to p‐xylene.



16

Figure 11 Production processes of methane, ethylene, propylene and mixed‐C4 from NG or propane

Figure 12 Production processes of methane, ethylene propylene and mixed‐C4 from naphtha or gas oil

Figure 13 Production processes of benzene, toluene and xylene



17

2.2.2 Intermediate petrochemical Process

Intermediate petrochemical industrial process uses upstream products as feedstock for

downstream production industry. Intermediate products can be divided into the following

classes:

Olefin Intermediates

Aromatic Intermediates

Alkane Intermediates

The production process of Intermediate petrochemical is complex and differs from one

product to another. It is also related directly to downstream process. See Figure 14‐16

Figure 14 Production process of Vinyl Chloride Monomer (VCM)

Figure 15 Production process of Styrene Monomer (SM)



18

Figure 16 Production process of Pure Terephthalic Acid (PTA)

2.2.3 Downstream Production

Downstream petrochemical industrial process relies on upstream and intermediate

production process in producing what is to be converted to final products. Downstream

products can be grouped as follows:

Plastic Resins, compose of

• Commodity Plastics

• Engineering Plastics

• High Performance Plastics

Synthetic Fibers

Synthetic Rubbers, Elastomers

Synthetic Coating and Adhesive Materials

Polymerization is a major process for production of downstream petrochemicals. This

process involves the combination of monomers into long chain polymer. Typically,

polymerization process requires the use of catalysts, heat and pressure in order to achieve

complete reactions. Polymerization may be performed by several methods such as:

Gas phase polymerization under high pressure and temperature

Solution phase polymerization under high pressure and temperature

Bulk or batch polymerization under moderate pressure and temperature

Suspension polymerization under moderate pressure and temperature

Emulsion polymerization under moderate pressure and temperature



19

Figure 17 Production process of LDPE

Figure 18 Production process of LLDPE by solution phase polymerization

Figure 19 Production process of LLDPE by solution phase polymerization



20

Figure 20 Production process of PVC by suspension polymerization

VCM

Raw Material

Polymerization ReactorSlurry Stripper

Latex Storage and Seiving

Dryer Classifier

Storage

Packing

PVC Resin

Raw Material Storage and Preparation

VCM Recovery

Grinding

Figure 21 Production process of PVC by emulsion polymerization

Figure 22 Production process of PP



21

Figure 23 Production process of PVC Resin

Figure 24 Production process of PP by gas phase polymerization

Figure 25 Production process of ABS



22

3.1 Energy Consumption Index

Appropriate calculation of indices of energy consumption in the petrochemical industry

used in Thailand and worldwide are: Specific Energy Consumption (SEC) and Energy Intensity

(EI). Assessment is necessary in order to lead to development of plant efficiency. SEC is

calculated from the energy that a plant consumes during a cycle of operation, for example, one‐

month, per product of that same period. EI is defined as the proportion between the energy

consumed in the production process the country’s gross domestic product (GDP) or other unit

such as ton of product, production value, transport value, etc. The energy consumed being

analyzed differently depending on its source, for example, heat, electricity energy, or total

energy. The calculation method is as follows:

( )(Ton) ProductsPrimary

(MJ) nConsumptioEnergySECnConsumptioEnergySpecific =

Energy Consumption = Purchased Fuel + Plant Fuel – Export Utilities

Primary Products = Main Product (Ton)

( ) ⎟⎠⎞

⎜⎝⎛=MMBahtTOE

ProductsPrimaryof Value

nConsumptioEnergyEIIntensity Energy

Energy Consumption = in unit ton of oil equivalent (TOE) Value of primary product = value of primary products in million baht per ton

The indices will be tremendously helpful in monitoring and controlling energy

consumption. Therefore, plants should monitor them recorded monthly. The collecting data

can reflex whether consumption is increasing or decreasing, and be used for energy

benchmarking as a useful tool for evaluating the efficiency of the plant.

3. ENERGY CONSUMPTION IN PETROCHEMICAL INDUSTRY



23

The scope of this study focuses only petrochemical plants; it does not include gas

separation plants and oil refineries. It assesses plants according to their products, from

upstream products ‐‐ olefins plants and aromatic plants ‐‐ to downstream, stopping at plastic

resin plants, and excluding plastic compounding and other industries.

The energy consumption figures used are drawn from the main production process; it

does not cover utilities, transportation, and offices units. The analysis takes into account all

factors that affect operation efficiency. For example, in the case of olefins plants, where other

products are manufactured in addition to the main products, only the olefins being ethylene and

propylene will be considered, not mixed C4 or other olefins, which are in much smaller

quantities, of unstable prices, and not the main target products of the plants.

3.2 Specific Energy Consumption (SEC)

Analysis results of the assessment of the 30 plants joining the study project are

presented in term of overall average, maximum and minimum values of the years 2003‐2006, as

shown in Table 5 and in sections 3.2.1 to 3.2.3.

Table 5 Range of specific energy consumption (SEC) in MJ/Ton of upstream intermediate and downstream petrochemical industry in year 2004‐2006

Petrochemicals Products SEC

(MJ/Ton)

Upstream

– Olefins Olefins (Ethylene, Propylene) 16,900 ‐ 24,900

– Aromatics Aromatics (B, T, X) 3,200 ‐ 17,100

Intermediate PTA, EB, SM, PA, EG, Polyol 1,900 ‐ 27,000

Downstream HDPE 2,700 – 3,600 PS, PP, EPS 1,000 – 2,000 Emulsion PVC, ABS, SAN, PC 2,700 – 12,500

The SEC value from the 30 participating plants reveals a rather wide range which can be

explained by the limited number of the plants existing in the country. The plants produce

different products, and even similar products are manufactured with different technologies and

processes. Nevertheless, compared to the USA (see Table 10), SEC value of petrochemical

industries in Thailand fall in almost the same bracket.

24

De

A Study o

kind of p

product

3.2.1

F

Ol

Table 6

2

16,00

av19

Tabl

because

5

10

15

20

25

Specific En

ergy Con

sumption (M

J/To

n)

epartment of

on Energy Effic

Also, consum

product, the

ion capacity,

Energy C

Figure 26 Sp

efins

Specific ene2003 – 2006

2003

0‐24,500

erage 9,892

le 6 shows t

e olefins prod

0

5,000

0,000

5,000

0,000

5,000

Ole

Alternative En

ciency Index in

mption of en

e raw materia

, etc.

onsumpti

pecific energ

rgy consump6

U

2004

17,000‐24,

average20,419

that SEC of o

duction requ

280,045

721,300

2003

efins A

nergy Develop

Petrochemica

nergy for dif

al used, tech

ion in Ups

gy consumpt

ption (SEC) o

Upstream PeSE

800 17,0

e a

olefin group

uires a more

2

727,164

2004

romatic

pment and Eff

al Industry

fferent prod

hnology, pro

stream Ind

tion (SEC) of

of upstream p

etrochemicaC (MJ/Ton)

2005

000‐25,100

average 21,092

of products

complicated

294,979

4

20Year

Production A

ficiency (DEDE

ducts vary in

duction proc

dustry

upstream pe

petrochemic

al‐Olefins

2006

16,500‐24

averag21,16

s is higher th

d process, mo

510,502

771,888

005

Aromatic

E)

quantity, d

cess, size of

etrochemica

cal industry –

6

4,900

ge 8

han the othe

ostly therma

505,354

839,46

2006

Production

epending on

the plant an

l industry

–olefins in ye

Average

21,227

er groups. Th

al cracking, w

4

66

0

100,000

200,000

300,000

400,000

500,000

600,000

700,000

800,000

900,000

Olefin

n the

nd its

ear

his is

which

Productivity (Ton)



25

consumes a lot more energy than intermediate and upstream industries. However, most of

these olefins producing plants use steam produced during the production process itself. They

even have surplus steam to sell to nearby plants. But in the data cited here, the sold amount is

excluded, and only energy consumed in the manufacturing of the products is taken into account.

This study finds that the SEC value from all olefins plants in Thailand does not differ

much from that of the same industry in other countries (as shown in Table 10). But the wide can

be explained by the fact that there are only 4 olefins plants in all of Thailand, each with a

markedly different production technology. In addition, only 2 main types of feedstock are used,

that is, ethane and naphtha. In producing olefins (ethylene and propylene) alone, the plants

using ethane as feedstock naturally consume less energy than those using naphtha, because

ethane is of smaller molecules, which can be cracked easily. But this does not mean that plants

using naphtha are of a disadvantage. In fact they do have valuable by‐products which they can

sell to compensate for the cost of energy.

Aromatics

Table 7 Specific energy consumption (SEC) of upstream petrochemical‐aromatics in year 2003‐2006

Upstream Petrochemical ‐ Aromatics SEC (MJ/Ton)

2003 2004 2005 2006 Average

3,000 ‐ 8,700 2,800 ‐ 8,500 3,300 ‐ 17,000 3,100 ‐ 17,000

6,987 average 5,708

average 5,425

average 8,146

average 7,960

Remarks: The values of SEC in 2003 and 2004 are lower than those of 2005 and 2006 because some of the participated plants did not collected data during those years. Thus SEC values for 2005 and 2006 are more realistic..

The upstream, aromatic production industry in Thailand consists of 4 plants, almost all of

which give importance to manufacturing 3 high value products – benzene, toluene and xylenes.

From studying the SEC value of this group of products, it is found that energy consumption also

has a wide range, again because aromatic plants in this country use different raw materials,

technologies and processes. In plants which use condensates as raw materials, the production

26

De

A Study o

process

xylene, a

product

3.2

Fig

Table 8

2

2,100

ave4,

Remarks

5

10

15

20

25

Specific En

ergy Con

sumption (M

J/To

n)

epartment of

on Energy Effic

is more com

and therefor

s and at larg

.2 Energy

gure 27 Spe

Specific ene2006

2003

‐ 10,300

erage ,533

*SEC for 20energy co

**Calculated consumpt

1

0

5,000

0,000

5,000

0,000

5,000

Alternative En

ciency Index in

mplicated th

re consume m

ger amounts.

y Consump

ecific energy

rgy consump

Int

2004

1,900 ‐ 10,5

average 4,659

006 is higher nsumption w

from all SEC vtion that start

135,454

ป 25462003

nergy Develop

Petrochemica

an the ones

much more e

ption in In

consumptio

ption (SEC) o

termediate PSECav

500 1,900

av4

than those oas starting up

values from 2 operating in

146,287

ป 2547

Intermediate

2004

pment and Eff

al Industry

s that use by

energy. How

ntermedia

n (SEC) of int

of intermedia

Petrochemic

verage (MJ/Ton

2005

0 ‐ 10,500

verage 4,659

of other yearsp that year.

003‐2006 exc2006

139,

ป 25 20

ficiency (DEDE

y‐products su

wever, they c

ate indust

termediate p

ate petroche

cal Industry n)

2006*

1,900 ‐ 28,

average4,841

s because one

ept one partic

,368

548

Producti

005

E)

uch as raffin

an produce

try

petrochemic

mical indust

,000

e

e participated

cipated plant

174,277

ป 2549

ion

2006

nates and m

more varieti

cal industry

try in year 20

Average

4,685**

d plant which

which high en

-

50,000

100,000

150,000

200,000

250,000

ixed‐

es of

003‐

high

nergy

Productivity (Ton)

PA,

stag

adju

the

raw

norm

Tabl

9

SpecificEn

ergy

Consum

ption(M

J/To

n)

The SEC

EG and Poly

ge of opera

ustments we

products are

materials m

mally more e

3.2.3 Ene

Figure 28

le 9 Specific

2003

900‐12,000

average 3,993

0

5,000

10,000

15,000

20,000

25,000

Specific En

ergy Con

sumption (M

J/To

n)

De

C value of pl

yol) has a rat

ation and t

re not yet in

e numerous

markedly va

energy is nee

ergy Consu

Specific ene

c energy cons

20

900‐1

aver3,6

121,623

ป 25462003

partment of A

ants produc

ther high (Ta

their energy

n place, maki

(PTA, EB, SM

aried. How

eded, and th

umption in

ergy consum

sumption (SE

Downstrea

006

11,900

rage 652

124,

ป 25

SEC Downstre

2004

Alternative En

A Study

cing interme

able 8) espe

y conservat

ing the amou

M, PA, EG a

wever, to pr

e by‐product

n Downst

mption (SEC) o

EC) for Down

am Petroche

SEC (MJ/T

2005

900‐15,00

average3,610

,225

547

eam

4

nergy Develop

on Energy Effi

diate petroc

cially in 200

ion measur

unt of energ

nd Polyol), a

roduce high

ts are usually

ream Pet

of downstrea

nstream Petr

emical Indus

on)

2

0 1,800

av3

139,739

ป 2548

Downstream

2005

pment and Effi

iciency Index in

chemical pro

6 when plan

res and/or

gy quite high

and producti

value petr

y high in valu

rochemica

am petroche

rochemical y

stry

2006

0‐11,000

verage 3,601

147,069

ป 2549

Production

2006

iciency (DEDE

n Petrochemica

oducts (PTA,

nts were in t

production

. In addition

ion technolo

ochemical p

ue as well.

al

emical indust

year 2003‐20

Averag

3,712

9

-

50,00

100,0

150,0

200,0

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al Industry

EB, SM,

their first

process

n to that,

ogies and

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try

006

ge

2

0

00

00

00

00

Productivity (Ton)

27



28

The SEC value of plants producing downstream products (HDPF, PS, PP, EPS, PVC, ABS, SAN and

PC) averaged out during 2003 and 2006 also has a rather high discrepancy (Table 9). This is

because most of the industry (the participating plants in this study project) produces mainly

plastic resins ‐‐commodity plastics and specialty plastics. Usually specialty plastics such as

thermosetting plastics consume more energy, because the process is more complicated. Even

among commodity plastic production plants, the amount of energy consumed varies. Special

grade plastics such as the medical‐grade consume higher energy than lower‐grade plastics.

3.2.4 Energy Consumption in Other Countries

Table 10 summarizes the energy consumption of petrochemical products in other

countries. The data shows the difference in SEC from product to product. The energy

consumption depends mainly on products. The difference in technologies, processes, and raw

materials contribute to the difference in SEC.

Table 10 Specific energy consumption (SEC) of petrochemical products in other countries

Product SEC (MJ/Ton)

SEC average (MJ/Ton)

Olefins 12,561 ‐ 25,120 18,841

Aromatics (BTX) 2,310 ‐ 3,521 2,917

Ethylene Glycol (EG) 3,488 ‐ 6,017 4,753

Ethylbenzene 3,028 ‐ 3,498 3,263

Styrene monomer (SM) 33,396 ‐ 45,113 39,255

Terephthalic acid (PTA) 3,121 ‐ 5,145 4,134

Polyethylene (PE) 1,483 ‐ 3,993 2,738

Polypropylene (PP) 1,129 ‐ 1,260 1,195

Polyvinyl chloride(PVC) ‐ 2,896

Source: Energetics Incorporated, 2000



29

Table 11 Specific energy consumption (SEC) of petrochemical products in Thailand and other countries

Products USA Thailand

SEC (MJ/Ton) SEC (MJ/Ton)

Olefins 12,561 ‐ 25,120 16,900 – 24,900

Aromatics (BTX) 2,310 ‐ 3,521 3,200 – 17,000

Ethylene Glycol (EG) 3,488 ‐ 6,017

1,900 – 10,500 Ethylbenzene 3,028 ‐ 3,498

Styrene monomer (SM) 33,396 ‐ 45,113

Terephthalic acid (PTA) 3,121 ‐ 5,145

Polyethylene (PE) 1,483 ‐ 3,993 2,700 – 3,600

Polypropylene (PP) 1,129 ‐ 1,260 1,000 – 2,000

Polyvinyl chloride(PVC) ‐

3.3 Evaluation of Energy Intensity (EI)

Energy Intensity (EI) was evaluated as energy in term of Ton of Oil Equivalent (TOE) per

value of one ton of product (million baht). The data from energy auditing of participated plants

and the value of petrochemical products in 2006 from Petroleum Institute of Thailand was used

in the calculation.

Table 8 Energy Intensity, EI (TOE/million baht) for petrochemical industry between 2003‐2006

Petrochemicals Products EI

(TOE/mil Baht) EI

(MJ/1,000 Baht)

Upstream

Olefins Olefins (Ethylene, Propylene) 0.98 ‐ 1.5 410 – 630

Aromatics Aromatics (B, T, X) 20.4 ‐ 10.5 100 – 440

Intermediate PTA, EB, SM, PA, EG, Polyol 0.79 – 5.0 30 – 210

Downstream HDPE, PS, PP, EPS, PVC, ABS, SAN, PC 0.26 – 3.3 10 ‐ 140

30

De

A Study o

Figur

aromati

petroche

product

product

intensity

product

the ener

epartment of

on Energy Effic

re 29 Energy

Energy inten

c upstream,

emical is co

is normall

s with down

y (EI) of petr

as indicated

However, on

rgy consume

1

1

Upstream: Ol

Upstream: Ar

Intermediate

Downstream

Spec

ific

Ener

gy C

onsu

mpt

ion

(TOE

/Mil B

aht)

Alternative En

ciency Index in

y Intensity, E

nsity, in the

, intermedia

omplicated a

y cheaper t

nstream prod

ochemical p

d in Figure29

nly a small r

ed, does less

0.00

5.00

10.00

15.00

efins

romatic

11.7

nergy Develop

Petrochemica

I (TOE/millio2

petrochemic

ate and dow

and consum

than produ

duct s which

roducts tend

eduction of

en the total

2003

11.73

3.51

2.57

1.35

3

3.51

2.57

1.35

pment and Eff

al Industry

on baht) for P2003‐2006

cal industry d

wnstream pr

ed more en

cts from ot

h consume le

d to decrease

energy cons

energy cons

2004

12.04

3.30

2.56

1.22

12.04

3.30 2.5

ficiency (DEDE

Petrochemic

decreases in

oducts. As

nergy than o

ther catego

ess energy a

e from upstr

sumption, fo

umption in t

20

12

4

2

1

12.44

4

56

1.22

E)

al Industry b

order from

indicated e

other proce

ries. Comp

and sell at h

ream produc

or example, 2

the industria

005

2.44

.96

.57

.18

1

.96

2.57

1.18

between yea

olefin upstre

earlier, upstr

sses. Upstr

paring upstr

igh price, en

ct to downstr

2‐5 percent o

al sector.

2006

12.49

5.01

2.55

1.23

2.49

5.01

2.55

1.2

rs

eam,

ream

ream

ream

nergy

ream

of all

23



31

The petrochemical industry requires high energy consumption. Therefore energy is a

vital factor in the business competition, because it has a direct effect on the production cost.

And for this reason, the state sector and the private businesses involved are turning their

attention to the conservation of energy, from organizing activities in the organization,

advertising and promoting awareness, to setting measures to conserve energy in both the

production sector and the service sector. But since the petrochemical industry depends greatly

on technology and highly specific expertise, very much unlike most other industries, it is

therefore capital intensive. This study project which compiles all related information, facts and

figures, analyzes the strength, weaknesses, opportunities and threats (SWOT), assesses and

recommends directions for the promotion of energy conservation, which can lead to adoption of

plans for effective conservation of energy.

4.1 Problems in Petrochemical Industry

Problems in the conservation of energy in the petrochemical industry can be divided into the following 4 respects:

1) Energy management

Lack of a unified source of information on the industry, either on the production process or energy use

Lack of central coordination, information compilation, advice and counseling needed for good management and efficiency

Lack of support in research and education to develop production technology and manage the industry in a complete cycle

2) Technology

Dependence on machinery and advanced technology from abroad

3) Economy

High cost of machines and technology as well as maintenance, as a capital intensive industry

Expensive raw materials such as natural gas, crude oil, and machinery parts imported from abroad

4) Human Resource

Need for advice and technology transfer from foreign experts

Lack of local expertise

4. THE PROMOTION OF ENERGY CONSERVATION

32

De

A Study o

4.2 SW

SStren

Nth

Mcl

Than

Th

OOppo

Th

Thov

Be(C

En

Thereof th

Short-T

Medium

Long-T

epartment of

on Energy Effic

WOT Ana

ngths

atural resouhe country

Most of the puster

he plants andnd in new co

he local mar

ortunities

he domestic

here is roomverseas

enefits from CMD)

nergy price is

R

e should be e industry, a

Entrepreneupolicies can

Plans shouldproduce furt

F

Term Plan

m-Term Plan

Term Plan

Alternative En

ciency Index in

lysis

rces can be f

lants are loc

d machineryondition

ket is consid

market is ex

m for market

carbon emis

s high

Recommend

a petrochemaiming at sus

urs should shbe centralize

d be mappedther energy f

Figure 30 En

•

nergy Develop

Petrochemica

found within

ated in a

y are up‐to‐d

erably large

xpandable

growth

ssion trading

dations For

mical managstainable co

hare utilitiesed, and dem

d out to add vfrom by‐prod

nergy manage

• 0-3 ye

• 3-5 ye

Up to 5 ye

pment and Eff

al Industry

WWeak

n

ate

Loen

Tefo

Pe

TThrea

g

Co

Th

Tr

r Energy Con

gement plan nservation o

, so that eneand‐supply r

value to by‐pducts.

ement plan in

ears

ears

ears

ficiency (DEDE

knesses

ogistic managnough

echnological reign counte

ersonnel in th

ats

ompetitors a

here is oversu

ade barrier m

nservation

which integof energy

ergy loss canrisks can be

products in a

petrochemica

1) EnergyManageme

3) Economic

E)

gement is no

developmenerparts

he field are n

re of an adva

upply at pres

measures are

Planning

grates the di

n be minimizminimized a

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y ent

2)Techno

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ot efficient

nt still relies

not enough

antage

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e enforced

ifferent aspe

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cycle, or even

) ology

Human source

on

ects

use

n to



33

4.3 Promotional Plan For Energy Conservation In The Petrochemical

From the study of problems found in the petrochemical industry, the SWOT analysis, and

the above recommendations by project advisors, the following plan is roughly drafted for the

different aspects and in different stages:

Energy conservation plan

Short‐term (0‐3 yrs) Mid‐term (3‐5 yrs) Long‐term (up to 5 yrs) Targets

1. Energy Management 1. Create awareness

in energy conservation.

1. Create creativity in energy conservation.

1. Create an energy saving culture.

Energy saving culture is created

Energy consumption is reduced in the long run.

2. Encourage large‐scale entrepreneurs to develop their own energy management to increase energy use efficiency.

2. Encourage small‐scale entrepreneurs in the converter industry to use energy efficiently.

2. Encourage all petrochemical entrepreneurs to continually manage energy wisely

Energy is used efficiently

Production efficiency is accelerated and below‐standard products are weeded out.

Energy cost is reduced

3. Plan for a central utility system to be shared in the industrial sector.

3. Manage central utility systems for ample sharing, e.g. wastewater treatment, different types of electricity plants for use in the industry

3.Promote the system of integrated complex management of shared utilities such as energy recover, and management of by‐products.

Energy loss is minimized, or energy is recovered

Production in the industry is a complete cycle and of highest efficiency

4. Set up a central body to compile databases for the industry.

4.The central body must have good knowledge management, be able to disseminate up‐to‐date information and give advice and suggestions to entrepreneurs

4. The central body must be able to use information and knowledge in benchmarking, and assist entrepreneurs.

There is a good system of knowledge management, with the use of databases which are constantly updated

Knowledge is shared on a constant basis.

The whole industry is developed in the same direction



34


Short‐term (0‐3 yrs) Mid‐term (3‐5 yrs) Long‐term (upto 5 yrs) Targets

2. Technology Management

1. Encourage learning of know‐how from abroad and research in production technologies that improve efficient use of energy.

1. Promote research and development in production technology and the application of research by entrepreneurs who have potential

Furnace upgrade /replacement

Repair Leaks and Improve fractionation efficiency

Develop catalysts

Reactor design/ Improve fractionators efficiencies

Recover heat from flue gas and recover steam from blow‐down

Develop energy management software

2. Deliver research study to pilot entrepreneurs subject

Deliver research study to amendment production process of pilot factory in order to select best practice factory of Petrochemical Industry

1. Carry out research and development on a regular basis

Disseminate the know‐how of Best Practice

Encourage entrepreneurs to apply research results in improvement of energy use in their industry

Knowledge and Best Practice of the industry are used as guidelines

The whole system of petrochemical production is improved, including emission reduction, energy efficiency, and value adding.



35


Short‐term (0‐3 yrs) Mid‐term (3‐5 yrs) Long‐term (upto 5 yrs) Targets

3. Economics Dimension

1. Use economic and financial tools as incentives for entrepreneurs to save energy

Reduce tax on import of machines and equipment that help increase energy efficiency.

1. Use economic and financial tools to help entrepreneurs to develop production technology that help increase energy efficiency

Give special preferences to entrepreneurs who are able to save energy.

1. Use economic and financial tools to encourage entrepreneurs to increase sustainable energy efficiency

Give special preferences/ waive taxes for entrepreneurs who have joined in sustainably reducing energy consumption

The industry develops efficiency in energy use in the long run

Entrepreneurs are interested in participating in the project

4. Human Resource Development Dimension

1. Develop human resource in the petrochemical industry.

Conduct training programs to create understanding and increase efficiency in energy conservation, such as seminars to exchange views on Best Practice

Conduct short training courses for upstream, intermediate and downstream industry entrepreneurs as well as converter industry entrepreneurs

1. Develop human resource in the petrochemical industry

Send personnel (in the state and private sectors) to take courses/study trips in petrochemical production abroad, so that they will come back to train others in turn

1. Develop human resource at all levels of education in the petrochemical industry

Offer programs in energy, such as energy conservation, energy management, etc.

The number of petrochemical experts is increased

Dependence on foreign experts is reduced



36

Energy conservation measures in the petrochemical industry can be divided into two levels:

1) Development and improvement of production technology

2) Energy efficiency improvement for processes and equipments

5.1 Development and Improvement of Production Technology

There are 2 major types of energy that have been used in the production processes of

petrochemical industries; thermal and mechanical energies. Mechanical energy is used to

control the working conditions of the equipments, i.e. control the system pressure, mixing the

chemicals. Mechanical energy mostly generated from electrical energy. Thermal energy is used

in many activities, such as preheat raw materials before entering reactors, heat for chemical

reactions, and energy for chemicals separation.

Energy conservation is achieved by changing and improving production process

technologies to facilitate less energy consumption, i.e. reduce the production temperature

and/or reduce the production pressure. The following section provides few developed

technologies that have been applied to petrochemical industries.

Some Technologies Developed for the Petroleum and Petrochemical Industry

Technology Sample

1) Process Control Natural networks, Knowledge based system

2) Process Optimization and Integration Analytical tools, Site integration, Advance process control

3) Catalytic (Catalyst and Reactor) Catalysts with Higher selectivity, Increase life time

4) Reactor Design, Advance distillation column

Process intensification, Reactive distillation, Dividing‐wall column

5) Bio‐technology for treatment facilities Bio‐feedstock, Bio‐Treatment

6) Combustion technology Low NOx burner, High efficientcy burner

7) Utilities Reverse osmosis (RO), Low maintenance pump

8) Power Generation Co‐generation, Gasification, Power recovery

9) Others Dehydrogenation, Hydro‐pyrolysis (non‐catalytic), Byproduct upgrading technologies, Using heavy feedstock

5. TECHNOLOGIES AND MEASURES FOR ENERGY CONSERVATION IN THE PETROCHEMICAL INDUSTRY



37

5.1.1 Catalysts

For all petrochemical production processes, catalysts are vital basis for chemical reaction

and process efficiency in the refinery. Catalysts are used in the main refining processes such as

hydroheating, reforming, hydrocracking, alkylation, and isomerization. Catalysts can improve

the production efficiency and reduce the energy consumption by increasing the conversion rate

of chemical reactions, increasing the selectivity of chemical reactions, reducing the rate of side‐

reactions, and/or improving the reaction condition by reducing the process pressure and/or

temperature.

The main directions for research and development of catalyst is on improving the

production process efficiency by higher activity, longer life, lower cost catalysts that can

optimized process conditions. In general, each catalyst is specific to each production process,

i.e. it cannot be applied to all production plants with similar products but different production

processes. The selection of appropriate catalyst for each specific process requires proper study

and research.

Source http://hisina.en.alibaba.com

Source: http://amtintl.com/reactorinternals.htm

Catalyst

Benefits of catalyst to energy saving

First, catalysts reduce the activation energy of chemical reactions and allow the reaction to be carried out at lower temperature and pressure. For example, catalyst reduces the activation energy for C‐C bonds rupture and cracking can be done at moderate temperature and pressure in comparison to steam cracking.

Second, catalysts increase the selectivity of chemical reactions; reduce the rate of side reactions

Third, catalysts remove coke which is formed

during the cracking process. Coke, de‐coked during catalyst regeneration, reduced energy efficiency of the process by hindering heat transfer is constantly removed by catalyst that are in turn‐decoke through catalyst‐regeneration (or catalyst‐decoking)



38

5.1.2 Distillation and Separation

The example of technologies for separation processes improvement are Vacuum Swing

Adsorption Process (VSA), Mechanical Vapor Recompression (MVR), advanced distillation

columns, membrane and combined refrigeration systems. In VSA process, solid sorbents with

high selectivity for light olefin, such as ethylene and propylene, over paraffin (such as ethane and

propane) is used to improve energy efficiency. MVR can be used in conventional

propane/propylene splitter. These techniques can reduce energy consumption by 5 percent in

comparison to steam cracking.

5.1.3 Membrane Technology

Membrane is one of the well established technologies for many production processes.

However, its application in steam cracking is quite limited. Membranes are usually made from

polymer such as polypropylene or inorganic materials. Membrane technologies can be applied

in the separation processes of olefin and paraffin, gasses in hydrogen recovery unit, and coke

and water in water purification process. In general, the application of membrane technologies

in petrochemical industries is still in the developing stage. The major drawbacks of the

technology are the inability of membrane to withstand severe operating conditions. It also

requires regular replacement and maintenance.

Advanced Distillation Column

Advanced distillation column technology has been developed since 1930s. One type of such column is divided‐wall distillation. Divided‐wall column integrates two conventional distillation columns into one column in order to increase heat transfer efficiency. Divided‐wall columns for butadiene extraction can save 15 percent of specific energy consumption in comparison to conventional butadiene distillation. Other advanced distillation column

technologies are Extractive distillation, Reactive distillation, and Azeotropic distillation.



39

source U.S. Department Of Energy, 2002

Figure31 Current and proposed hybrid technology for the separation of isoprene from a

C5 mixture

5.1.4 Power Generation

Petrochemical industries, especially the upstream plants, consume a lot of energy.

Many of these plants have their own electrical and energy production units. These units are vital

for plants energy saving. The industry is identified as one of the industries with highest potential

for application of co‐generation or Combined Heat and Power production. Petrochemical

processes use energy in the form of heat, steam, cooling, and electricity extensively. Co‐

generation power plants utilize waste heat, which considered loses in standard plants. In

addition, transportation losses are minimized when power generation units are located in the

plant vicinities.

In applying the energy conservation technologies to the petrochemical industries,

studies on the advantages and disadvantages, and their effects are necessary. Most of the

petrochemical process technologies are imported and process modification requires

permission from the producer, or licensor. Although adaptation of the technology for a

specific process may reduce energy consumption, the technology cost may exceed that of the

reduced amount of energy. So it may not be wise to do so. A case in point is the substitute of

a new catalyst which can work at lower temperatures. The licensor has to give permission to

make sure that it will work, since the change could affect other equipment previously

designed for a certain catalyst. Also, the new catalyst used usually costs more. Hence

cost/benefit assessment should always be carried out before any modification.



40

5.2 Energy Efficiency Improvement for Processes and Equipments และปรับปรุงที่ใชในกระบวนการผลิต

5.2.1 Energy Management

A systematical management is another important approach for efficient use of energy.

An organization‐wide energy management program creates a foundation and provides guidance

for energy management throughout the organization. Most petrochemical plants have a

responsible unit for energy management. Smaller plants may not have this designated unit and

opportunities for improvement may not be promoted due to some limitations such as the lack of

coordination between internal units, misunderstood support given to efficient energy use

projects, financial limitations, or lack of good financial management, etc.

.

[Energy Management System, EMS]

An EMS should start with a commitment within the organization to seriously develop and improve energy usage on a continual basis. Top administrators of the plant must be sincerely willing to engage in it. A policy must be established for the use and conservation of energy, and a team set up to oversee the policy implemented. An action plan must be mapped out in stages, with regular assessment of the performance, using figures collected at intervals, technical assessment and benchmarking. By doing so, administration can improve the baseline and set goals for future developments..

Energy Management System



41

5.2.2 Steam generation

Steam generation is an important unit in the refinery (Figure 32). Steam is used

throughout the petrochemical production process. In the U.S.A, it is estimated that 30 percent

of energy used in the refinery is in the form of steam. Steam can be generated by process waste

heat recovery, cogeneration and boilers. Steam is expensive to produce and supply and is non‐

storable. Therefore, the used of steam should be carefully considered and assessed since the

efficiency improvement in steam generation and distribution are possible.

Source: Worrell and Galitsky, 2005

Figure 32 Steam generation process

Steam is used in many of the petrochemical production processes, i.e. process heating,

drying or concentrating, steam cracking, and distillation. Figure 33 shows how steam is loss from

the system during the production processes (U.S.Department of Energy, 2005).

Guide to saving energy for steam generation system

• Boiler Feed Water Preparation

• Improved Process Control

• Reduce Flue Gas Quantities

• Reduce Excess Air

• Improve Insulation

• Maintenance

• Recover Heat from Flue Gas

• Recover Steam from Blow down

• Reduce Standby Loss



42

5.2.3 Steam Distribution System

Velocity and pressure drop are the key parameters in the designing of steam distribution

system. The cost and energy loss are higher for oversize steam pipe while a too small pipe may

lead to erosion and higher pressure drop. Steam demands can change over time, and

occasionally steam may be underutilized. It may be too costly to adjust the system for changed

steam demand. However, checking and shutting off the excess distribution lines can effectively

reduce steam losses. Other energy saving measures in the steam distribution system is

summarized as follow:

Figure 33 Steam losses in steam distribution system

Guide to saving energy in the steam distribution system

• Improve Insulation

• Maintain Insulation

• Improve Steam Trap

• Maintenance Steam Trap

• Automatically monitoring of steam trap

• Repair Leaks

• Recover Flash Steam

• Return Condensate



43

5.2.4 Heat exchangers

Heat exchangers are common operations in refinery process. Steam is heated and

cooled many times during the process. The optimum design and control of the equipment can

significantly affect energy consumption efficiency.

Most processes in a complex refinery occur under high temperature and pressure,

therefore managing and optimizing heat transfer among processes is very important to energy

saving. A deposit in heat exchanger units and piping, fouling, hinders heat transfer and increases

energy consumption

5.2.5 Process heater

The furnaces and boilers in a petrochemical plant consume over 60 percent of the total

fuel. The efficiency of heater can be improved by improving heat transfer characteristics and

flame luminosity, installing of recuperators or air‐preheaters, and improving the control system.

New burners have been designed to improve air and fuel mixing and to be more efficient heat

transfer. Other burners such as lean‐premix burners, swirl burners, pulsating burners and rotary

burners are also improved. Safety and environmental issues, such as reduction of NOx, has to be

addressed in selecting these new burners.

Guide to energy saving in heat transfer system

• Maintenance : Regular maintenance of burners, draft control and heat exchangers is essential to maintain safe and energy efficient operation of a process heater

• Air‐preheating:

• New Burner: New burner technology reduces cost for operation and emissions treatment

Fouling in Heat exchangers

Operation and design can be the causes of fouling. There are several methods that attempt to reduce fouling including using sensors for early warning, physical and chemical methods to create high temperature coatings, using ultrasound, as well as improving the design and operation of facilities. Current researches are focusing on principle of fouling and redesign of heat exchangers and reactors. Methods for fouling reduction are focusing on process and temperature control, regular maintenance and cleaning of heat exchanger and, retrofit of reactor tubes



44

5.2.6 Distillation

Distillation is a process which uses energy to separate products on the basis of boiling

points. Heat comes from process heaters and/or steam. Energy saving in this process can be

achieved by optimizing distillation column.

Energy saving opportunity in distillation column

• Operation Procedure: The optimization of the reflux ratio of the distillation column can make significant energy savings.

• Check Product Purity: The reflux rate should be decreased in small increments until the desired purity is obtained.

• Reducing Re‐boiler Duty

• Upgrade Column Internals: New tray designs can result in enhanced separation efficiency and decrease pressure drop

• Stripper Optimization: Optimization of these parameters can reduce energy use considerably

5.2.7 Motors

Petrochemical facilities use electric motors in many stages of production, consuming

over 80percent of total electricity. Equipments with electric motors include pumps (60% of all

motor use), compressors (15%), fans (9%), and other equipments (16%). Systematic approach

for optimizing the demand and supply of motor system instead of focusing on individual

components often provides the most energy savings.

Guide to energy saving in motor system (Motor optimization)

• Sizing of Motors: Motors and pumps that are sized inappropriately result in unnecessary energy losses

• High Efficiency Motors: High efficiency motors reduce energy losses through improved design, better materials, tighter tolerances, and improved manufacturing techniques

• Power Factor: The power factor can be corrected by minimizing idling of electric motors

• Voltage Unbalance

• Adjustable Speed Drive (ASDs) Variable Speed Drives (VSDs) : ASDs better match speed to load requirements for motor operations



45

5.2.8 Pumps

Pumps use 60 percent of electricity use for motors which is approximately 50 percent of

the total electrical energy in refineries. It is estimated that over 20 percent of energy use for

pumps can be saved by optimizing equipment and/or control system. In fact, priority should be

given to cost in this investment, since the lifetime of pumps can be up to 20 years.

Pumping systems include a pump, a driver, pipe, control systems such as adjustable

speed drives, and a part of the overall motor system. Systematic approach for optimizing the

motor system also includes pumping system. The main approaches for optimizing the pumps

operation are reducing friction, or adjusting the system to the best efficiency point (BEP)

indicated in the pump curve. Friction can be reduced by correcting the pipe size, using surface

coating and polishing, and adjusting the pump speed drives.

Guide to energy saving in pumping system (Pumps)

1) Operation and Maintenance: Better maintenance will reduce these problems and save energy

• Replacement of worn impellers, especially in caustic or semi‐solid applications.

• Bearing inspection and repair.

• Bearing lubrication replacement, once annually or semiannually.

• Inspection and replacement of packing seals. Allowable leakage from packing seals is usually between two and sixty drops per minute.

• Inspection and replacement of mechanical seals. Allowable leakage is typically one to four drops per minute.

• Wear ring and impeller replacement. Pump efficiency degrades from 1 to 6 points for impellers less than the maximum diameter and with increased wear ring clearances

• Pump/motor alignment check.

2) Monitoring

• Wear monitoring

• Vibration analyses

• Pressure and flow monitoring

• Current or power monitoring

• Differential head and temperature rise across the pump (also known as thermodynamic monitoring)

• Distribution system inspection for scaling or contaminant build‐up

3) Reduce need

4) More Efficient Pumps

5) Correct Sizing of Pump and Matching Pump to Intended Duty

6) Use Multiple Pump: using multiple pumps is the most cost‐effective and most energy efficient solution for varying loads



46

Guide to energy saving in pumping system (Pumps) cont’d

7) Trimming Impeller or Shaving Shaves

8) Controls: shut off unneeded pumps or reduce the load of individual pumps until needed.

9) Adjustable Speed Drive (ASDs) or Variable Speed Drives (VSDs)

10) Avoid Throttling Valve : Extensive use of throttling valves or bypass loops may be an indication of an oversized pump

11) Correct Size of Pipes : Correct sizing of pipes should be done at the design or system retrofit stages where costs may not be restrictive

12) Replace Belt Drives

13) Precision Castings, Surface Coatings and Polishing: The use of castings, coatings, or polishing reduces surface roughness that in turn, increases energy efficiency.

14) Sealing

5.2.9 Air Compressors

Air compressor is equipment that consumes a lot of energy in the burner. Large‐sized air

compressors may use electric motors, steam turbines or gas turbines

Guide to energy saving in compressor

1) Compress air maintenance

• Blocked pipeline filters increase pressure drop. Keep the compressor and intercooling surfaces clean and foul‐free by inspecting and periodically cleaning filters. Keep motors and compressors properly lubricated and cleaned.

• Inspect fans and water pumps for peak performance.

• Inspect drain traps periodically to ensure they are not stuck in either the open or

• closed position and are clean

2) Proper monitoring and maintenance

3) Reduce leaks in pipes and equipment

4) Reducing the Inlet Air Temperature.

5) Maximize Allowable Pressure Dew Point at Air Intake.

6) Properly Sized Regulators.

7) Sizing Pipe Diameter Correctly.

8) Adjustable Speed Drives (ASDs).

9) High Efficient Motors



47

5.2.10 Fans

In the petrochemical facilities, fans are used at boilers, burners and cooling towers. Their efficiency varies according to the fan types (Figure 34).

Energy saving opportunity in fans

• Fan oversizing: However, it may often be more cost‐effective to control the speed than to replace the fan system.

• Adjustable Speed Drives, ASDs: Significant energy savings can be achieved by installing adjustable speed drives on fans

• High efficiency belts (Cog Belts).

Figure 34 Typical belts use in motor system



48

This study classify the petrochemical industries and assesses the energy consumption

index of each group, for the purpose of assessing the potential and basedline of energy

conservation and giving recommendations for systematical and efficient energy conservation in

upstream, intermediate and downstream industries. Data concerning the technologies and

energy conservation measures used by plants are compiled and evaluated for the benefit of the

overall industry.

Petrochemical plants are grouped on the basis of the product, into upstream,

intermediate and downstream plants, and information is collected of the years 2003‐2006, from

30 sample plants participating in the project. The indices used for the study are Specific Energy

Consumption (SEC) and Energy Intensity (EI). It is found that in general the plants have good

monitoring of their production, with the exception of some producing under capacity or

temporary shutdown for repair. Comparison of energy use at the plants finds that energy

consumption indices have a wide range, even between plants producing the same products. This

can be explained by the use of different raw materials and/or production technologies, as well as

the small number of entrepreneurs there are. However, analysis results reveal data not much

different from other countries, and that Thailand’s petrochemical industry is consuming less

energy.

There are 2 levels of energy conservation: in the development and improvement of the

production technology, and in management and improvement of the efficiency of equipment in

energy consumption. Catalyst technology has a very significant role in the manufacturing of

products due to reduce operating condition i.e., pressure and temperature, particularly catalysts

in the reforming, hydrocracking, alkylation and isomorization processes. Also effective in the

production system are reactor design and advanced distillation and separation process. For

example, membrane technology can increase equipment efficiency markedly. So does

improvement of power generation by combine heat and steam or co‐generation. Development

of the system must go hand in hand with management and improvement for efficient use of

existing equipment. In addition to this, there should be a monitoring and quality control system

in place.

Unlike other industries, the petrochemical industry requires advanced and specific

technology and expertise. This study finds that the main problems and obstacles in energy

conservation lie in the lack of a centralized/coordinated database needed for good and efficient

SUMMARY



49

management, support of research and development in the production technologies, complete

cycle of management of the industry, as well as expert consultants. Added to this, this is an

industry which relies heavily on advanced technological machinery entirely from abroad, making

the cost very high and dependent on the global market and the fluctuation of the Baht currency.

Therefore, in promoting energy conservation, the problems should be solved in short, medium

and long terms, respectively, using a concrete success energy index.

In addition to recommendations given here, training programs are designed to support

further conservation of energy by giving basic knowledge concerning conservation of energy and

acceleration in efficiency of its use, enhancing the potential of participants as experts in the

field, particularly in petrochemical management standards, testing and analysis of energy

consumption, and energy saving projects. A website is also designed, with the purpose of being a

channel for coordination and follow‐up of trainees and organizations concerned. Also being

developed are database software for the recording and processing of related data such as

energy consumption data, production data, energy use indices, technologies/standards of

energy saving, etc. which can link up with the Department of Alternative Energy Development

and Efficiency.

Fruitfully, this study project is carried out with the objective of presenting feasible ways

to promote efficient energy conservation, in both production technology and energy

management. It includes in‐depth measures for efficient energy conservation and sustainable

human resource development. The ultimate goal is for the petrochemical industry to make the

most of the energy used, thus increasing Thailand’s competitive edge and its ability to tackle the

present and future global energy crisis.

****************************



50

1. Boon‐Long. S., PTIT Focus Special Annual Issue 2005, Rungsiri Publishing: Bangkok, 2005.

2. California Energy Commission. (2004), Energy Efficiency Roadmap for Petroleum Refineries in California (DRAFT Final Report)

3. Gielen, D. J., Vos, D. And Drill, Van A.W.N. The Petrochemical Industry and Its Energy Use: Prospects for the Dutch Energy Intensive Industry (1996). (ECN‐C‐96‐029). The Energy research Centre of the Netherlands (ECN). Retrieved from http://www.ecn.nl/publications/default.aspx?nr=ECN‐C‐‐96‐029 on September, 2006.

4. Guidelines for Energy Management Overview. Retrieved from http://www.energystar.gov on September, 2006.

5. Kruesarn, R. and Rachabungsa, K. Who’s Who in the Petroleum and Petrochemical Industries of Thailand, 5th Ed; The Petroleum Institute of Thailand (PTIT), 2005.

6. Margaret, W. G. Handbook of Petrochemicals and Process, Brookfield, VT: Gower, 1991.

7. Phylipsen, D., Blok, K., Worrell, E., and Beer, J. D. Benchmarking the energy efficiency of Dutch industry: an assessment of the expected effect on energy consumption and CO2 emissions, Energy Policy, 30, 663‐679. 2002.

8. Phylipsen, D., Worrell, E. and Blok, K. (1995). Parameters Affecting Energy Consumption in the Petrochemical Industry, Proceedings ECEEE 1995 Summer Study, June 2‐6,1995, Manlieu, France

9. Ren, T., Patel. M. and Blok, K. (2004), Energy Efficiency And Innovative Emerging Technologies For Olefin Production, Parallel Session Innovative Energy Efficiency Examples Of Different Industrial Sectors ‐Energy Efficiency In The Cement, Metal And Petrochemical Industry.

10. Robert , A. M., Handbook of Petrochemicals Production Processes, McGraw‐Hill, USA., 2005.

11. The Office of Energy Efficiency and Renewable Energy (2004), Separation Of Olefin/Paraffin Mixtures With Carrier‐Facilitated Transport Membranes Use of Membranes Could Significantly Reduce Energy Costs, Industrial Technologies Program, The U.S. Department Of Energy.

12. U.S. Department of Energy (2002), Novel Modified Zeolites for Energy‐Efficient Hydrocarbon Separations, Industrial Materials for the Future. Office of Industrial Technologies Energy Efficiency and Renewable Energy — U.S. Department Of Energy Project Fact Sheet.

13. U.S. Department of Energy (2002), Olefin Recovery From Chemical Industry, Waste Steams Membrane Separation Recovers Olefins From Gaseous Waste Steams For Use As Chemical Feedstocks. Office of Industrial Technologies Energy Efficiency and Renewable Energy — U.S. Department Of Energy Project Fact Sheet.

14. U.S. Department of Energy Office of Industrial Technologies (2000). Energy and Environmental Profile of the U.S. Chemical Industry, prepared by Energentic Incorporated, Columbia, Maryland.

15. Worrell, E. and Galitsky, C. (2004). Profile of the Petroleum Refining Industry in California, California Industries of the Future Program, Ernest Orlando Lawrence Berkeley National Laboratory.

16. Worrell, E. and Galitsky, C. (2005). Energy Efficiency Improvement and Cost Saving Opportunities for Petroleum Refineries. An ENERGY STAR® Guide for Energy and Plant Managers.

17. Worrell, E., De Beer, J. G., Faaij, A. P. C. and Blok, K. (1994). Potential Energy Savings in the Production Route for Plastics, Energy Convers. Mgmt 35, p 1073‐1085.

18. Worrell, E., Phylipsen, D., Einstein, D. and Martin, N. (2002). Energy Use and Energy Intensity of the U.S. Chemical Industry (LBNL‐44314), Lawrence Berkeley National Laboratory, Berkeley, CA.

19. ความรูเบื้องตนปโตรเคมี. จุลสาร บริษัทอุตสาหกรรมปโตรเคมีกัลไทย จํากัด. 2536.

REFERENCES



51

20. โครงการฐานขอมูลดานการผลิต และการซ้ือขายผลิตภัณฑปโตรเคมี. เอกสารการวิจัย วิทยาลัยปโตรเลียมและปโตรเคมี. จุฬาลงกรณมหาวิทยาลัย. 2531.

21. ภาวะอุตสาหกรรมปโตรเคมี. สํานักงานเศรษฐกิจและอุตสาหกรรม. จาก

http://www.oie.go.th/industrystatus2_th.asp. ตุลาคม 2549.

22. วีรพจน ลือประสิทธิ์สกุล. ความรูเกี่ยวกับอุตสาหกรรมปโตรเคมีและการพัฒนาอุตสาหกรรมปโตรเคมีในประเทศไทย.

บริษัท เดียรบุค จํากัด: กรุงเทพ ฯ. 2535.

23. วีรพล จีรประดิษฐกุล. สถานการณและนโยบายพลังงานไทย. เอกสารสรุปผลการประชุมกลุมยอยทางวิชาการครั้งที่ 2. สํานักงานนโยบายและแผนพลังงาน. 2548.

24. อํานาจ สิทธัตตระกูล. อุตสาหกรรมปโตรเคมี. ภาควิชาวิทยาการและวิศวกรรมวัสดุ คณะวิศวกรรมศาสตรและเทคโนโลยีอุตสาหกรรม มหาวิทยาลัยศิลปากร. 2533.

REFERENCES (CONT’D)



52

LIST OF ABBREVIATION

ABS Acrylonitrile Butadiene Styrene

MUSD Million United State Dollar

ACN Acrylonitrile MX Mixed Xylene

BMA Butyl methacrylate NG Natural Gas

BR Butadiene Rubber NGV Natural Gas for Vehicles

CFR Cost and Freight OX or O‐Xylene

Ortho‐Xylene

DDI Domestic Direct Investment PA Phthalic Anhydride

E&P Exploration and Production PBT Polybutyl Terapthalate

EDC Ethylene Dichloride PDH Propane Dehydrogenation

EG Ethylene Glycol PE Polyethylene

EO Ethylene Oxide PET Polyethylene Terephthalate

EPDM Ethylene Propylene (Diene) Monomer

PMMA Polymethyl Methacrylate

EPS Expandable Polystyrene POM Polyoxymethylene

EVA Ethylene Vinyl Acetate PP Polypropylene

FDI Foreign Direct Investment PS Polystyrene

GDP Gross Domestic Product PTA Pure Terephthalic Acid

HDPE High Density Polyethylene PVA Polyvinyl alcohol

HR Human Resource PVC Polyvinyl Chloride

IMP.R/M Imported Raw Material PX or P‐Xylene

Para‐Xylene

KTA Kilo Ton Per Annual SAN Styrene Acrylonitrile

LDPE Low Density Polyethylene SBL Styrene Butadiene Latex

LLDPE Linear Low Density Polyethylene

SBR Styrene Butadiene Rubber

LPG Liquefied Natural Gas SEA South East Asia

MEG Monoethylene Glycol SM Styrene Monomer

MMA Methyl Metacrylate UPR Unsaturated Polyester Resin

MMSCF Million Standard Cubic Feet VCM Vinyl Chloride Monomer

MTBE Methyl Tertiary‐Butyl Ether

The Department of Alternative Energy Development and Efficiency (DEDE)

LOGOwww.themegallery.com

The Department of Alternative Energy Development and Efficiency (DEDE)

Ministry of Energy

17 Rama I rd.Pathumwan BKK. 10330Tel 0-2223-2311 Fax 0-2226-3943

petrochemical industry - dedee-lib.dede.go.th/mm-data/bib11162.pdf1.2 types of petrochemical...

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