AN INVESTIGATION INTO PET PLASTICS AND PET RECYCLING:

Name

Instructor’s name

Course

Date

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Table of Contents:

1.1 Abstract…………………………………………………. 4

2.1 Introduction…………………………………………….. 5

3.1 Literature review……………………………………….. 8

4.1 Background Information……………………………….16

4.1.1 Research questions and Hypotheses………………….18

4.2 Methodology…………………………………………...19

5.1 Results………………………………………………….20

6.1 Discussion………………………………………………30

7.1 Conclusion………………………………………………34

8.1 Recommendations……………………………………….36

9.1 References……………………………………………….40

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Commonly used terms and abbreviations:

PET - Polyethylene Terephthalate

HDPE- High-Density Polyethylene:

PVC- Polyvinyl chloride:

LDPE- Low-Density Polyethylene:

DMT- Di Methelene Terephthalate.

PP- Polypropylene.

PS- Polystyrene

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1.1Abstract:

The project is about the PET plastics and PET recycling. This is a process of recycling

plastics that are recyclable from the environment. PET is a thermoplastic polymer resin

belonging to the polyester family. It is basically used in the manufacture of synthetic

fibres, food and beverage liquid containers. Other uses include the thermoforming

applications and the engineering resins where it is often mixed with glass fibre.

On the methodology, research has shown that mixing starch with plastic will lower

degradation, but it still doesn't lead to complete breakdown of the plastic. Bacteria have

been genetically engineered to synthesize a completely biodegradable plastic, but this

material is expensive at present.

Recycling of plastics reduces the trash deposited in landfills, and offers the opportunity

for consumers to clean and reuse containers for everything from water spritzer bottles to

holding excess amounts of shampoos, cleaning fluids or lotions. Recycling all plastic

bottles that contain PET or HDPE labels somewhere on the bottle, most often found on

the neck of the bottle to make separation of recyclable and non-recyclable plastic easier

on consumers is a better remedy.

It is recommended that the current bottle bills should also be expanded even to other

countries. In 2005, 2 million tons of plastic bottles in the United States ended up in the

trash instead of in recycling bins. The State container deposit law which is known as

"bottle bills" are long overdue for an upgrade. They have proven to be the most effective

approach to collecting bottles and cans. Currently, only 11 states have bottle bills in

America.

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2.1 Introduction:

Plastics are indeed everywhere, from the grocery to the shopping mall. They are

important in the packaging industry, but a closer look at the plastics brings into focus the

price to be paid by using and dumping it the wrong way. This therefore calls for a lot of

care. Before you toss that plastic bag to the environment then be sure of the impact you

are creating. Plastics are very durable and this means that they will degrade very slowly

therefore takes long in the environment. Decomposition by burning also creates serious

toxic fumes in the atmosphere. The production as well takes significant amount of fossil

fuels which pollutes the environment (Tukker, 2002). Several plastic debris remains

floating on the sea surface and this creates danger to the marine life. Most sea animals

have died due to the ingestion of plastic materials. Solar radiation degrades plastics into

smaller particles which eventually becomes plastic dust and goes to pollute the

atmosphere.

The acronym PET stands for Polyethylene terephthalate. This is a thermoplastic polymer

resin belonging to the polyester family. It is basically used in the manufacture of

synthetic fibres, food and beverage liquid containers. Other uses include the

thermoforming applications and the engineering resins where it is often mixed with glass

fibre. The monomer can be processed in several ways and these include: The

esterification of terephthalic acid and ethylene glycol with water as the by product. It can

also be synthesized through transesterification of ethylene glycol and dimethyl

terephthalate with methanol as the by product. Finally it can be polymerized through

polycondensation of the monomers with water as the by product.PET is commonly

5

referred to as polyester and is the third most abundant plastic production behind

polyethylene and poly propylene (Tierney & John 2006). It is widely used in the

production of synthetic fibres.

Due to this damage to the environment, it is therefore imperative to develop ways of

recycling the plastics and this brings us to the actual project that is PET plastics and PET

recycling. The objective of the project is basically to reduce plastics in the environment

through recycling. It also aims at developing appropriate measures to deal with the plastic

menace. The project also focuses on achieving a clean environment which is safe to live

in. It also aims at fostering recycling of plastics as the best option to keep them off the

environment.

The recycling processes with polyester are as varied as the manufacturing processes

based on primary pellets. Polyester can be used today in most of the polyester

manufacturing processes as blend with virgin polymer or increasingly as 100% recycled

polymer. This will depend on the purity of the recycled materials. There are some

exceptions like BOPET-film of low thickness, special applications like optical film or

yarns through FDY-spinning at > 6000 m/min or microfilaments and micro-fibers that are

produced from virgin polyester only.

There exist a number of internal recycling processes where fibre is reused directly to

produce fibre and the same to both performs and films. In a nut shell the following

general simple procedure is used in the process. First is the bale opening then followed by

the sorting and selection for different colours, foreign polymers. Next is the pre-washing

without cutting before the cutting process. Stones are then removed and other debris like

6

glass and metal. Air sifting is done to remove film paper and labels. It is then ground and

low density polymers removed. Hot wash is done followed by caustic wash to maintain

intrinsic viscosity. After which the rinsing is done twice. It is then dried and followed by

air sifting flakes before sorting the flakes automatically. Water circuit and water

treatment technology is then employed to attain flake quality.

There exist some defects which are encountered during the process. They can be grouped

into several categories. The reactive polyester –OH or –COOH end groups could be

transformed into non reactive end groups like the formation of vinyl ester end group. The

end group could also shift towards the direction of the –COOH end groups. This would

be due to build up during thermal and oxidative degradation. The number of poly-

functional macromolecules could also increase. The number, variety and concentration of

non- polymer identical organic and inorganic compounds may increase.

They can be detected either chemically or physically through the following processes.

Increase of –COOH end group, increase of color number B, increase of oligomer content,

reduction in filterability, increase of by products like acetaldehyde, increase of

extractable foreign contaminants, decrease in colour L, decrease ofl intrinsic viscosity,

decrease of crystallization temperature and increase in crystallization speed, decrease in

mechanical properties like tensile strength, broadening of molecular weight distribution.

The statement of the problem to the project states that although plastics are very

important to the users, proper disposal through recycling is required to avoid massive

environmental degradation.

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3.1 Literature Review:

Plastics have a major impact in the society due to poor disposal. Most marine lives,

human lives and even the terrestrial animals’ lives have been lost due to this menace of

plastics. This therefore calls for the appropriate measures to curtail the problem. The

most appropriate method is then use of then recycling technology to keep the plastic

materials out of the environment.

On the other hand there are scholars who claim the benefits of plastic materials outweigh

their negative impact to the environment (Thomas & Visakh 2011). Some of the benefits

floated include: In electronics, laptops could not function well in case they were made

from glass. Plastics are used in building and construction as a cheaper material as

compared to the others. They are indeed very useful in the packaging industry. Plastics

have slowly taken over the normal paper in the packaging industry. Plastics are very

durable and their manufacture is very cheap. It can as well be recycled rather

decomposing it. This can be achieved easily than producing a new one. Plastics can be

reused over and over again as opposed to the aluminum materials. They do not corrode as

does with the metals. They are not breakable as with the glass materials. Plastics are light

in weight and are usually odourless and thus can be used to carry most things.

PET is an acronym that stands for Polyethylene terephthalate. This is a thermoplastic

polymer resin belonging to the polyester family. It is basically used in the manufacture of

synthetic fibres, food and beverage liquid containers. Other uses include the

thermoforming applications and the engineering resins where it is often mixed with glass

8

fibre. The monomer can be processed in several ways and these include: The

esterification of terephthalic acid and ethylene glycol with water as the by product. It can

also be synthesized through transesterification of ethylene glycol and dimethyl

terephthalate with methanol as the by product. Finally it can be polymerized through

polycondensation of the monomers with water as the by product.PET is commonly

referred to as polyester and is the third most abundant plastic production behind

polyethylene and poly propylene. It is widely used in the production of synthetic fibres.

Due to the addition of polyvinyl alcohol, there is a reduction in oxygen permeability.

PET is considered an excellent barrier material as some health practitioners use gloves

made of this material. It is usually used in tape applications like in the carrier for

magnetic tape or the backing for pressure sensitive adhesive tapes due to its high

mechanical strength. Thermoformed PET can be used in the storage of frozen dinners.

This is because of their ability to withstand extreme temperatures. Nylon is a product of

PET. It is naturally strong with high strength and ability to form several products. PET

has a variable intrinsic viscosity range.

The process of manufacturing PET takes distinct stages. The initial stage is the Drying

stage. This is achieved since PET is hygroscopic. Drying is achieved by the use a

desiccant. This is basically achieved by the passage of a series of hot air through the

material. It can also be done by the use compressed air. The next stage is the modification

through copolymerization. An example is where the melting point can be lowered

through the addition of cyclohexane dimethanol. Copolymerization is very important in

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the thermoforming and in the crystallization process like the material used in the seat

belts. Crystallization of polymers occurs when a polymer chains fold to form some

repeating pattern.

PET is considered a semi-crystalline polymer since only 40% of the polymer is

amorphous. The solid state crystallization is a process in which PET is crystallized to

glass like substance through a very rapid cooling process. For the process to make

effectively, a catalyst must be employed in the form of Antimony trioxide (Sb2O3).

Exposing PET to boiling or microwave could increase levels of antimony. This could be

detrimental to the health status of individuals who consume products packaged with such

material. Environmental Health Perspectives in April 2010 claims that PET might yield

endocrine disruptions. Contrary to this Franz and Welle gave evidence based on

mathematical modeling claiming that PET is unlikely to yield endocrine disruptions when

consumed in mineral water.

The degradation process of PET takes different forms like the hydrolytic, thermal

oxidation and the thermal which is the most important. This degradation process leads to

discolouration, chain scissions due to reduced molecular weight and the formation of

other products like the acetaldehyde and crosslinks. This interferes with the optimal

requirements especially in the packaging industry. The best way to alleviate this menace

is through the use of copolymers. These will lower the melting point and reduce the

degree of its crystallinity. The use of stabilizers like phosphites which are mainly

10

antioxidants can also stabilize the polymer. Acetaldehyde can cause foul taste in bottled

water when formed onto the walls of the container.

There are two ways employed in the recycling of PET. They are the chemical and the

mechanical. The chemical process destroys all the structure thereby forming new

intermediates like cis-ß-hydroxyterephthalate. In mechanical recycling, the original

properties of the polymer are being maintained. Chemical recycling comes in handy

when large tones of the product are needed within a very short time. Mechanical

recycling is used in small and medium scale industries. Apart from the general

contaminants from the first stage of formation, mechanical impurities depreciate the

quality of the recycling process. This calls for efficient sorting, cleaning and separation

process in order to attain optimum results.

The industry consists of three major sections: The Waste Logistics section where

collection and separation of wastes is done (Porter, 2002). The Flake production section

where clean bottles are produced. The Flake Processing section where PET flakes are

converted to final products. There exist a number of internal recycling processes where

fibre is reused directly to produce fibre and the same to both performs and films. In a nut

shell the following general simple procedure is used in the process. First is the bale

opening then followed by the sorting and selection for different colours, foreign

polymers? Next is the pre-washing without cutting before the cutting process. Stones are

then removed and other debris like glass and metal. Air sifting is done to remove film

paper and labels. It is then ground and low density polymers removed. Hot wash is done

11

followed by caustic wash to maintain intrinsic viscosity. After which the rinsing is done

twice. It is then dried and followed by air sifting flakes before sorting the flakes

automatically. Water circuit and water treatment technology is then employed to attain

flake quality.

The defects encountered during the process can be grouped into several categories. The

reactive polyester –OH or –COOH end groups could be transformed into non reactive

end groups like the formation of vinyl ester end group. The end group could also shift

towards the direction of the –COOH end groups. This would be due to build up during

thermal and oxidative degradation. The number of poly-functional macromolecules could

also increase. The number, variety and concentration of non- polymer identical organic

and inorganic compounds may increase.

These can be detected chemically or physically through the following processes. Increase

of –COOH end group, increase of color number B, increase of oligomer content,

reduction in filterability, increase of by products like acetaldehyde, increase of

extractable foreign contaminants, decrease in color L, decrease of intrinsic viscosity,

decrease of crystallization temperature and increase in crystallization speed, decrease in

mechanical properties like tensile strength, broadening of molecular weight distribution.

There are several examples for processing polyester. The recycling processes with

polyester are as varied as the manufacturing processes based on primary pellets. Polyester

can be used today in most of the polyester manufacturing processes as blend with virgin

polymer or increasingly as 100% recycled polymer. This will depend on the purity of the

recycled materials. There are some exceptions like BOPET-film of low thickness, special

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applications like optical film or yarns -spinning at > 6000 m/min or microfilaments and

micro-fibers that are produced from virgin polyester only.

The processes include simple re-pelletizing of bottle waste into flakes. This involves

transforming bottle waste into flakes, by drying and crystallizing the flakes, by

plasticizing and filtering, as well as by pelletizing. The product is an amorphous re-

granulate of an intrinsic viscosity in the range of 0.55–0.7 dl/g, depending on how

complete pre-drying of PET flakes has been done. They have to be crystallized and dried

before further processing. Processing is done in order to obtain the following a PET film

for thermoforming, addition of PET virgin production, packaging film, PET bottle resin

by SSP, Carpet yearn, Engineering plastic, Filaments, Non woven materials, Packaging

stripes, Stable fibre. By selecting the re-pelletizing way means having an additional

conversion process which is at the one side energy intensive, causes thermal destruction

and cost consuming. On the contrary, pelletizing step is providing the following

advantages: intensive melt filtration, intermediate quality control, modification by

additives, product selection and separation by quality, increased processing flexibility,

and quality uniformity.

The other process is the manufacture of PET pellets or flakes for bottles. This is a bottle

to bottle process. It is similar to the one described above in principle; however, pellets are

directly crystallized and then subjected to a solid-state polycondensation (SSP) in a

tumbling drier or a vertical tube reactor (Piringer, 2000). The corresponding intrinsic

viscosity of 0.80 – 0.085 dl/g is re build again and, at the same time, the acetaldehyde

content is reduced to 1 ppm in this process. Besides its’ approval it is nevertheless

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important that any user of such processes has to constantly check the limits for the raw

materials manufactured by himself for the process.

There is also the direct conversion of bottle flakes. This is done to minimize costs.

Polyester intermediate producers like spinning mills, strapping mills or cast film mills are

working on the direct use of the PET-flakes, from the treatment of used bottles, with a

view to manufacturing an increasing number of polyester intermediates. It is possibly

necessary to reconstitute the viscosity through polycondensation in the melt phase or

solid-state polycondensation of the flakes in order to adjust the viscosity. The application

of twin screw extruders, multi-screw extruders or multi-rotation systems and coincidental

vacuum degassing to remove moisture and avoid flake pre-drying are indeed the current

PET flake conversion processes. They allow the conversion of non-dried PET flakes

without substantial viscosity decrease caused by hydrolysis. About 70% is of PET bottle

flakes are converted to fibers and filaments.

In direct secondary materials such as bottle flakes in spinning processes, there are a few

processing principles to obtain. The first being the high speed spinning process for the

manufacture of POY. This needs a viscosity of 0.62–0.64 dl/g. The viscosity can be set

via the degree of drying beginning from the bottle flakes. For full dull or semi dull yarn

the use of TiO2 must be added. An efficient filtration of the melt is necessary for the

protection of spinnerets. Staple fibres may also be spun in an intrinsic viscosity range

which lies lower and which should be between 0.58 to 0.62 dl/g. The viscosity can be

adjusted via drying or vacuum adjustment in case of vacuum extrusion. However, the

addition of chain length modifiers like ethylene glycol or diethylene glycol may be used.

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The basic spinning non-woven in the field for textile applications as well as heavy

spinning non-woven as basic materials, for example in roof covers or in road building

where it can be manufactured by spinning bottle flakes. The spinning viscosity is again

within a range of 0.58–0.65 dl/g. The manufacture of high tenacity packaging stripes and

monofilaments is another area of great interest. The initial raw material is a recycled

material of higher intrinsic viscosity. The monofilaments as well as the high tenacity

packaging stripes are then manufactured in the melt spinning process.

The recycling of PET back to the initial raw materials takes three major processes. The

first one being the glycolysis or partial glycolysis process. The polyester is transformed

into an oligomer by adding ethylene glycol or other glycols during thermal treatment. The

advantage of this process is the possibility of separating the mechanical deposits directly

and efficient through a progressive and stepwise filtration (Mantia, 2002). The decisive

effect on the quality of the end product depends on the filteration finess of the last step.

This demonstrates how bottle waste can successfully be recycled in a continuously

operating polyester line. The quality of the bottle pellets which are manufactured on the

line are maintained with 10-25% bottle flakes feeding into the processor.

Temperature is brought to the lowest possible limit. The possibility of a chemical

decomposition of the hydro peroxides is possible by adding a corresponding P-stabilizer

directly when plasticizing. Treatment by adding H3PO3 in the last step helps in the

destruction of hydro peroxide groups. The finely filtered recycled and partially

glycolyzed material is continuously fed to the esterification or prepolycondensation

reactor. Dosing quantities are adjusted accordingly. Japan has used the treatment of waste

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through total glycolysis to convert polyester to Cis-B hydroxyl-terephthalate in

experimental production.

The next process is through hydrolysis which operates under very high pressures and

supercritical conditions. PET-waste is directly hydrolyzed for example by applying

supercritical water steam. Re-crystallization in acetic acid will help in the purification of

crude terephthalic acid.

The final process is the methanolysis which is basically for the large scale production.

Polyester waste is transformed with methanol into DMT, under pressure and in presence

of catalysts. Filtration of the methanolysis product is then applied. Crude DMT is finally

purified by vacuum distillation. Methanolysis is only rarely carried out in industry today

since polyester production based on DMT shrunk tremendously and with this DMT

producers disappeared step by step during the last decade.

4.1 Background Information:

Plastics have had an impact on our culture. However, it has become obvious that there is

a price to be paid for their use. A controversy arose in the late 1950s and early 1960s

where there were a number of incidents where small children crawled into plastic bags

used by launderers to cover clothing, and suffocated to death.  Plastics industry fended

off the trouble by launching a massive public-education campaign. Most local authorities

now offer collection facilities for plastic bottles either from your kerbside collection

scheme or at recycling centres. By late 1960s plastics were seen as the symbol for

backwardness. However, this was just a fashion statement, since plastics remained in

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widespread use anyway, and in many cases were much more effective and

environmentally benign than alternative materials. It also came with problems of litter

and waste disposal. The invention is however credited to Nathaniel Wyeth of Du Pont

according to the American Patent No. 3733309 of 1973.

Plastic was generally good, as it was durable and degraded very slowly.  Burning of the

plastic material could release toxic fumes. The manufacture of plastics has generally

managed to create massive quantities of nasty chemical pollutants, and depleted the

Earth's bounded supply of fossil fuels. By the 1990s, Plastic recycling programs became

common in the 1990s (Lundquist, 2000). Thermoset plastics can be ground and used as

filler, thermoplastics can be re-melted and reused, though the purity of the material tends

to degrade with each reuse cycle.  Automobile machines are now being redesigned to

make recycling of their large plastic parts much easier and cheaper. The Plastic Bottle

Institute of the Society of the Plastics Industry devised the now-familiar scheme to mark

plastic bottles by plastic type in order to assist in the recycling of plastic disposable

items.  A container using this scheme is marked with a triangle with three "chasing

arrows" inside of it, which enclose a number giving the plastic type: PET, HDPE, PVC,

LDPE, PP, PS, and OTHER as shown in the table below.

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Plastic container code system:

MATERIAL PERCENT OF TOTAL

Polyethylene Terephthalate (PET) 20-30 percent

High Density Polyethylene 50-60 percent

Vinyl/Polyvinyl Chloride (PVC) 5-10 percent

Low Density Polyethylene 5-10 percent

Polypropylene 5-10 percent

Polystyrene 5-10 percent

All other resins 5-10 percent

4.1.2 Research questions and Hypotheses:

The assumptions of the study and the research questions are as follows:

i. Are plastics generally a menace to the environment and society at large?

ii. Can plastics be eradicated completely from our environment?

iii. What are the major cost benefit analyses of the plastic materials?

iv. What are the benefits of using PET plastics?

v. Are there other materials that can replace in the PET plastics in the common

market?

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vi. Recycling of PET is much better than producing new plastics.

vii. Recycling of PET reduces environmental pollution.

viii. Recycled PET is the material of choice to be used.

ix. Recycling PET comes with its’ demerits.

x. Recycling of PET reduces costs and is much cheaper than the virgin type.

4.2 Methodology:

Recycling plastics has proved to be very difficult. It is difficult to Automating the sorting

of plastic waste is very difficult, and so it is labor-intensive (Harper, 2000). Consumer

toy like a cellular phone may be made of many small parts consisting of over a dozen

different types and colors of plastics yet containers are usually made from a single type

and color of plastic, making them relatively easy to sort out. As the value of the material

is low, Recycling plastics is unprofitable and for this reason, the percentage of plastics

recycled is very small, that is around 5%.

Research is being conducted on "biodegradable" plastics that break down with exposure

to sunlight. By mixing starch with plastic degradation will be lowered, but it still doesn't

lead to complete breakdown of the plastic. Bacteria have been genetically engineered that

synthesize a completely biodegradable plastic, but this material is expensive at present.

Critics claim that their only real problem to be addressed is roadside litter, which is

regarded as a secondary issue.  When plastics are dumped into landfills, they can become

"mummified" and persist for decades even if they are supposed to be biodegradable.

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The Courtald, the original producer of rayon, came up with a revised process for the

material in the mid-1980s to produce tencel which has superior properties to rayon, but is

still produced from "biomass" feedstock, and its manufacture is extraordinarily clean by

the standards of plastic production. I believe that effective and consistent education

encourages consumers to recycle. When both adults and children understand how

recycled containers are re-processed and re-manufactured into new items, it helps them

understand and take ownership of the process.

For a successful recycling operation to be achieved, the following requirements must be

put into place. First of all acquire a very steady source of very high grade and competitive

materials. After which, establish a cost effective transportation and collection medium.

Create a recycling processing technology and indeed equipment that can handle the

material efficiently and economically. Ensure you develop the ability to market both

continuous and quality in the quantity of materials. Finally develop proper markets for

end products.

5.1 Results:

Not all plastics that go into the curbside recycling bin get recycled. Collecting plastics

brings the belief that, like aluminum and glass, the recovered material is converted into

new containers. None of the recovered plastic containers from Berkeley are being made

into containers again, but into new secondary products such as textiles, parking lot

bumpers, or plastic lumber which are all non recyclable products. "Recycled" just means

"collected," not reprocessed or converted into useful products.

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Curbside collection does not reduce the amount of plastic landfilled. This is because

people feel comfortable buying more when collection seems to be environmental

friendly. The programs might backfire if total use rises faster than collection The curbside

program only captures certain types of plastics thus most will end up in the landfills and

therefore the net impact of initiating curbside collection could be an increase in the

amount of plastic landfilled. According to Berkeley, no reduction of plastic being sent to

the landfill in the areas where the curbside collection was in operation was recorded.

Most plastic reprocessing leads to secondary products that are not themselves recycled

and thus temporarily diverted from landfills.

The chasing arrows symbols are misleading and are now considered meaningless. All are

marked with the chasing arrows symbol.Information in the symbol gives the general class

of resin used to make the container. Eleven attorneys general from different states

objected to false and misleading claims about plastic recyclability. The settlement that

they reached paves the way for a first-ever definition of what claims can or cannot be

made about plastic recycling and recyclability (Harper, 2000).

Plastic resins are not made from petroleum refineries’ waste, but from non-renewable

natural resources that could be used for a variety of other applications or conserved. It

could sound absurd, but plastics are made from the same natural gas used in homes to

heat water and cook. Plastic recyclers do not pay for the service. The advertisements are

paid for by the virgin resin producers. Their goal is to promote plastic sales. Their major

aim is to remove or otherwise diminish the greatest challenge to the market expansion

brought about by the virgin plastics. They also aim at elleviating the negative public

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conception of plastic as unrecyclable, environmentally harmful, and a major component

of wastes that must be landfilled or burned.

Using plastics will not conserve energy. Manufacture of new plastic uses as much energy

as making glass containers from virgin materials. It also uses more energy than in the one

used in making glass containers from recycled materials. Refillables are the most energy

conservatives.

There are other choices to be adopted which include using refillable containers, buying in

bulk, buying things that don’t need much packaging, and buying things in recyclable and

recycled packages.

There are economic, health, and environmental costs and benefits of plastics. It is flexible

and light weight, but on the other hand creates problems including: consumption of fossil

resources; pollution; high energy use in manufacturing; accumulation of wasted plastic in

the environment; and migration of polymers and additives into foods (Eiri, 2007). The

producers do not use any recycled plastic in their packaging. Enactment of laws could

reduce the use of virgin resin for packaging. The virgin & endash plastics industry has

resisted such cooperation by strongly opposing recycled content legislation. It has instead

defeated or weakened consumer efforts to institute stronger laws. Plastic producers

decided that they will not add post consumer materials to their resins.

Establishing plastics collection might increase consumption by making plastic appear

more ecologically friendly both to consumers and retailers. Curbside collection could

legitimize the production and marketing of packaging made from virgin plastic. showed

No reduction of "recyclable" plastic containers being thrown away according to studies of

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garbage truck loads during the recent plastic pick-up pilot program (Harper, 2002).

Indeed there was a slight increase. Due in part to increased plastic use, Glass container

plants have been closing, including Anchor Glass Container Corporation in Antioch,

putting 300 people out of work.

Plastic recycling is costly and does little to achieve recycling goals. The cost benefit

analysis for implementing curbside plastics collection in Berkeley shows that curbside

collection of discarded plastics has several pitfalls. It involves expensive processing; has

limited benefits in reducing environmental impacts; and has limited benefits in diverting

resources from waste. Processing plastics costs more than virgin plastic. As they increase

production and reduce prices on virgin plastics, the markets for used plastic are

diminishing. Competition is too high for the PET recyclers. The capture of glass, paper or

yard debris in Berkeley could divert more resources from landfills than collecting plastics

at curbside.

However, there are some benefits associated with the recycling of plastics. It reduces the

trash deposited in landfills, and offers the opportunity for consumers to clean and reuse

containers for everything from water spritzer bottles to holding excess amounts of

shampoos, cleaning fluids or lotions. Recycling all plastic bottles that contain PET or

HDPE labels somewhere on the bottle, most often found on the neck of the bottle to make

separation of recyclable and non-recyclable plastic easier on consumers is a better

remedy.

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The PET bottle or jar that you place in a recycling bin today can be collected and

recycled into a wealth of products for tomorrow. PET can be recycled into new PET

containers, carpet, clothing, protective packaging, industrial strapping, automotive parts,

construction materials, even the felt for tennis balls, and tennis ball canisters (Gehrke,

2010). Because of PET's full recyclability and wide variety of uses, the market for

recycled PET is limited only by the amount of material that is collected from consumers

and recycling facilities. The development of new facilities that can recycle used PET

bottles into new food-grade PET bottles and containers (closed-loop recycling) is

expanding the resource efficiencies and sustainability of PET even further.

Cost Benefit Analysis of the Different plastics:

Net benefits ($/tonne) of recycling PET:

.

Text description of figure

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Dotted line = no externalities included; solid lines: high and low benefit estimates.

There are indeed encouraging and appealing net benefits for recycling PET for all

quantities that are recoverable. It further shows that the net benefit curves are generally

flat. They are decreasing relatively with increased quantities

Net benefits ($/tonne) of recycling HDPE:

Text description of figure:

This line graph shows the net benefits ($/tonne) of recycling HDPE. There are positive

net benefits for recycling HDPE for all quantities that are recoverable. It shows that the

net benefit curves are generally flat and thus is decreasing relatively with increased

quantities.

25

Net benefits ($/tonne) of recycling PVC:

Text description of figure:

This line graph shows the net benefits ($/tonne) of recycling PVC. Only the curve

representing the high benefit estimate shows positive net benefits. Both the curves

representing low benefit estimates and that with no externalities included show negative

net benefits. All curves are fairly flat, the net benefit decreasing (or negative net benefit

increasing) slightly with increased quantities.

26

Net benefits ($/tonne) of recycling LDPE:

Text description of figure:

This line graph shows the net benefits ($/tonne) of recycling LDPE. As with Figure 15,

only the curve representing the high benefit estimate shows positive net benefits. Both the

curves representing low benefit estimates and those with no externalities included show

negative net benefits. All curves are fairly flat, the net benefit decreasing (or negative net

benefit increasing) slightly with increased quantities.

From the four figures above we can deduce that there are positive net benefits for

recycling PET and HDPE for all quantities that are recoverable. On the other hand for

PVC and LDPE, the value of recycling depends crucially on the estimates made of the

value of external benefits and particularly the direct consumer benefits. It gives the total

quantity produced. This is through the use of current technologies. It further gives the

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quantities that could be recycled for each material with positive net benefits under high

and low benefit assumptions.

There are a number of strategies that can be used to curb the problems or menace above.

First is the reduction in the usage. Retailers and consumers can select products that use

little or no packaging. Choose packaging materials that are recycled into new packaging

such as glass and paper (Carl, 2005). Should individuals refuse plastic as a packaging

material, the industry will decrease production for that purpose, and the associated

problems such as energy use, pollution, and adverse health effects will diminish.

The other strategy is to foster and encourage the culture of re-using containers.

Containers can be reused about 25 times, container reuse can lead to a substantial

reduction in the demand for disposable plastic, and reduced use of materials and energy,

with the consequent reduced environmental impacts. Container designers will have to

consider the difference in the following policies "Design for service” and "design for

disposal". This will enable them to take into account the fate of the container beyond the

point of sale and consider the service the container provides.

The producers also need to take back resins as a major requirement. If manufacturers

directly involved with plastic disposal and closing the material loop, then this would

stimulate them to consider the product’s life cycle from cradle to grave. Reprocessing

should be made easier by limiting the number of container types and shapes, using only

one type of resin in each container, making collapsible containers, eliminating pigments,

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using water-dispersible adhesives for labels, and phasing out associated metals such as

aluminum seals. They can help develop the reprocessing infrastructure by taking back

plastic from consumers.

A legislature requiring that all containers be composed of a specific percentage of post-

consumer material will reduce the amount of virgin material consumed. There should be

a standardized form of labeling (Gleick, 2010). The chasing arrows should not mislead

the consumers unnecessarily. Different standardized labels for recycled, recyclable and

plastic type X should be developed. On the contrary, recycling saves money in disposal

costs, extends disposal capacity, conserves natural resources, creates jobs, and provides a

reliable, cost-effective feed stock to industry.

Plastic is one of humanity's greatest sins against the environment, a wrong for which only

recycling can salvage. Recycling of plastics comes with its’ negative impacts too. It

cannot be read as with simplicity, but elements like to save the planet, reducing

greenhouse gases and saving marine life must be given priority. The change brought

about in the environment by recycling plastics depends on what type of plastic is

collected, destination and the final product. Recycling helps reduce the amount of trash

going into landfills across the country and offers the opportunity to reprocess and re-use

items to create objects, fabrics and items that we never would have imagined.

Recycled plastics are used to create carpet fibers, clothing and dishes, among others.

When plastics are recycled or burned, they release toxic waste or fumes from chemicals

inside the plastic out into the environment. This is aggravated by the fact that some

recycling facilities don't take green plastic bottles, such as those used to create soft drinks

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like Mountain Dew or 7-Up. Recycling takes much time. Sorting and separation of daily

household or office trash takes time to separate papers from magazines, and clear plastic

from colored plastics. The numerous and variable usage of the plastic bottles brings a lot

of confusion. They hold everything from soda to ketchup and peanut butter or shampoos,

each which may require different handling or sorting instructions.

6.1 Discussion:

Consumers and businesses must participate actively in the recycling process in order to

gain most of the PET’s environmental sustainability and benefits. Though PET is the

most recycled plastic in the world at a rate of approximately 28%, there is still need to

improve in this sector accordingly to meet the demands of the people. It is however very

unfortunate that some individuals still carelessly toss their used bottles right into the trash

bin rather than putting them into the recycle bin (Board, 2007). These therefore end up in

landfills instead of being recycled for new uses. Due to its’ being inert and resistant to

micro-organisms, PET materials that go into the landfills will pose no risk of leaching or

contamination of groundwater. They at the same time take very little space since they are

easy to crush. About 1% of municipal solid waste is attributed to the PET.

PET containers can be collected or in other words recovered and re-used over again and

again. Reduction of waste, re-use of materials and recycling are the best processes so far

that can save the environment and the society at large. In order to attain a much more

sustainable future, it is indeed necessary to recycle PET bottles and containers. This is

because the process is simple and environment friendly. The production of new plastic

materials from already recycled materials indeed uses about 67% less energy than in the

30

manufacture of the products from virgin materials. This therefore implies that recycling

of plastics frees the energy that could be utilized somewhere else. For example in the year

2008 UK recycled over 5 billion pounds of plastic and this amazingly saved the energy

that could be used to heat over 2.5 million homes.

Greenhouse gas emissions arising from the extraction, pre processing and production are

significantly reduced with the substitution of recycled materials with the virgin materials.

Generally the recycled materials give an environmentally friendly source of producing

new products and substitutes for new plastics. The recycled materials make thousands of

everyday products. These include: fleece jackets, carpeting and lumber for outdoor

decking. The more plastics are recycled, the more of recycled plastics available.

Furthermore, the more plastics are bought then the more the industry shall create. Given

the current green trends, the demand for plastics may grow very exponentially. This is

given by the fact that the demand for plastic materials exceeds the industry’s supply. This

therefore calls for an elaborate recycling process to help meet the demands of the people.

Due to these factors the number of plastics recycling plants has tripled in the recent years.

Just imagine that the recycling of one tone of plastic saves about 7.4 cubic yards of

landfill space. Reduction is therefore an important achievement in the recycling industry.

New developments are also being carried out to ensure quality plastics are produced. For

example some bottled water producers are trying to reduce plastic in their production

which is otherwise known as light weighting in order to create an impact. The recycling

industry in response to this managed to reduce the weight of PET plastic water bottles by

nearly 33% between the year 2000 and 2008. Currently the average weight of 2 litre

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bottle of soda is about 19 grams lighter than it was in 1977. An approximate of 5.6 billion

bottles are sold every year therefore the simple source reduction has managed to

eliminate about 200 million pounds of plastic every year.

On the other perspective, recycling of plastics could help in eliminating the negative

impacts associated with plastics. Studies have suggested that most of the world’s fossil

fuels are used in producing new plastics. This accounts for millions of tons of fuels per

year in the environment. Therefore, recycling helps in the preservation of these fuels. It

goes ahead to encourage their use in other markets. Since all plastics recyclable, it should

be recycled as much as possible. This is on the contrary not being done so and thus leads

to massive accumulation of plastics in the landfills. It therefore clearly points out that

without proper recycling then the marine life is in complete danger.

The landfills are closing at an alarming. Two are being closed daily. This space crisis is

especially problematic in cities, where inner-city trash dumps are often filled to capacity,

and surrounding communities are unwilling to allow new landfills to come to their

neighbourhoods. Cities along the coast line use the ocean as a dumping ground, resulting

in depleted fish stock, polluted beaches, and other health issues for the inhabitants. Plastic

materials make up about 11% of the contents of landfills. So without this recycling

project then there is will no land in future for other developments. In order to save space

at landfills, plastics are often burned using incinerators. By doing this, chemicals,

petroleum, and fossil fuels used in the manufacturing process are released into the

atmosphere, adding to greenhouse gas emissions. Recycling would eliminate this by a

great margin.

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Most plastic containers float on the surface of the oceans. These at times can look like

food to larger sea animal, but it comes with fatal consequences. Sea birds, fish and other

ocean creatures often get caught in plastic rings that strangle them or constrict their

throats so that they cannot swallow. Imagine how recycling could save much life not only

to humans, but to animals also. Research is not quite clear on how long it takes for plastic

to biodegrade. Though it has not been round long enough, but amazingly the first plastics

made are still around today. However, plastics will take hundreds of years to degrade

fully or even much longer. Plastics have only been around for a hundred years, yet they

are already a problem. What amount of plastics will be in our landfills in about five

hundred years to come.

Plastics generally contain harmful chemicals which include, but not limited to the

following: cadmium, lead, PVC, and other pollutants in the form of artificial coloring,

plasticizers, and stabilizers (Bary, 2003). Some have been found to be harmful and are

not in currently manufactured plastics, but the older, more toxic plastics are still filling up

our landfills and floating around in our oceans, releasing pollutants into the environment.

They may find their way into groundwater from landfill runoff and cause health risks for

both wildlife and humans. Energy saved by recycling a single plastic bottle as compared

to producing a new one from scratch is enough to power a single 60-watt bulb for six

hours. This would power our homes on the energy savings we would gain by recycling

every one of those plastic bottles. It is a general fact that recycled plastic materials are

found in many unexpected places. These may include: carpeting, the fuzz on tennis balls,

scouring pads, paintbrushes, clothes, industrial strapping, shower stalls, drainpipes,

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flowerpots, and lumber. Plastics may also contain oils that could be recycled and reused

as fossil fuels.

The recycling process also came up with its hindrances or difficulties. The first problem

is the issue of contamination. According to nature of impurities, basic washing can solve

this menace. There is also insufficient supply of the plastics for recycling. Some plastics

are also too thin to recycle. Plastics have different molecular construction, practical

recycling will depend majorly on the ability to separate them from each other. This

therefore calls for recycling with proper sorting and packaging. Some consumers view

plastics as low quality associated with the low class individuals.

Some legislations also prevent the use of plastics. This is detrimental to the market

potential of the plastic products. Polymer prices are also very volatile due to the

inequality in capacity demand, stock building during the low price situations. The price

of virgin plastic is also linked to the oil price. The high collection costs hinder the general

process of recycling. Proper development of sorting machines will reduce collecting and

sorting costs and at the same time increasing the plastic streams quality.

7.1 Conclusion:

To crown up issues concerning PET Plastics and PET recycling, it is of importance to

note that this project is of indeed good value. PET containers can be collected or in other

words recovered and re-used over again and again. Reduction of waste, re-use of

materials and recycling are the best processes so far that can save the environment and

the society at large. In order to attain a much more sustainable future, it is indeed

34

necessary to recycle PET bottles and containers. This is because the process is simple and

environment friendly.

Research is not quite clear on how long it takes for plastic to biodegrade. Though it has

not been round long enough, but amazingly the first plastics made are still around today.

However, plastics will take hundreds of years to degrade fully or even much longer.

Plastics have only been around for a hundred years, yet they are already a problem. What

amount of plastics will be in our landfills in about five hundred years to come.

The production of new plastic materials from already recycled materials indeed uses

about 67% less energy than in the manufacture of the products from virgin materials.

This therefore implies that recycling of plastics frees the energy that could be utilized

somewhere else. For example in the year 2008 UK recycled over 5 billion pounds of

plastic and this amazingly saved the energy that could be used to heat over 2.5 million

homes.

Recycling of plastics could help in eliminating the negative impacts associated with

plastics. Studies have suggested that most of the world’s fossil fuels are used in

producing new plastics (Baird, 2004). This accounts for millions of tons of fuels per year

in the environment. Therefore, recycling helps in the preservation of these fuels. It goes

ahead to encourage their use in other markets. Since all plastics recyclable, it should be

recycled as much as possible. This is on the contrary not being done so and thus leads to

massive accumulation of plastics in the landfills. It therefore clearly points out that

without proper recycling then the marine life is in complete danger.

35

According to nature of impurities, basic washing can solve this menace. There is also

insufficient supply of the plastics for recycling. Some plastics are also too thin to recycle.

Plastics have different molecular construction, practical recycling will depend majorly on

the ability to separate them from each other. This therefore calls for recycling with proper

sorting and packaging. Some consumers view plastics as low quality associated with the

low class individuals.

8.1 Recommendations:

In the early 70’s not even a single curbside was found in any of the countries. Currently

they have grown to unimaginable numbers. Most countries manage to recycle third their

municipal waste. The rate of dumping still exceeds that of recycling. Increasing our

recycling rates will help pull us out of the garbage heap and reduce global warming

emissions. This brings us down to the realization that it is necessary to cut down on the

waste we produce in the first place. Recycling is one of the steps in a full loop of

practices that, together, will reduce the amount of waste going to landfills and cut back

on greenhouse gas emissions. It goes beyond bundling up newspapers and collecting

bottles. Manufacturers should use recycled materials to make their products, and

consumers should buy goods made from post-consumer recycled content in order to close

the loop created. Demand for products made with recycled materials should be increased

at the expense of virgin materials. This will eventually ensure a much more successful

recycling, divert waste from landfills, save natural resources and curb global warming.

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Other avenues to work towards a zero waste in the future are as follows: Organics and

recyclables should be kept out of landfills and incinerators. Approximately 60 percent of

household waste is recyclable or compostable, but only 8% are being composted.

Composting helps in preparing organic waste like leftover food and lawn trimmings for

reuse as fertilizer instead of leaving it to decompose in landfills or to combust in

incinerators, which emit greenhouse gases and other air pollutants. Creating More

municipal composting programs should be created to boost composting rates. The

programs exist in only a few cities, and they're outnumbered more than 2 to 1 by curbside

recycling programs.

We should also consider putting trash cans in our regular diets. What we dump in our

trash cans doesn't need to be there in whole. By adopting mechanisms of cutting back on

product packaging, promoting reusable bags over paper and plastic, using sponges

instead of paper towels, and favoring mugs or glasses over disposable containers, we are

indeed just reducing the waste.

There are also ways to boost the rates of recycling and also to curb the menace of global

warming. Throwing away our waste creates greenhouse gas emissions just exactly like

from driving our cars and heating our homes. Depositing garbage in landfills releases one

fourth of all methane gas emissions (Andrady, 2003). Contrary to most opinions, methane

gas is a global warming pollutant which is 22 times more potent than carbon dioxide.

Trash incinerators emit greenhouse gases. Therefore throwing away products rather than

reusing or recycling them often means burning more fossil fuels to strip virgin timber and

other raw materials from the earth. If we increase our recycling rate from the current 32.5

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percent to 35 percent, the effect on greenhouse gas emissions would be comparable to

removing a million passenger cars from our roads.

Managing the electronic waste is a major concern in the future. Used and dumped

electronics like old computers, broken cell phones, obsolete television sets will form the

fastest growing element of our waste stream. Laws are in place for nine states that require

the recycling of electronics, and several other states are working on new e-waste laws in

America. Most countries support legislations that put the responsibility on manufacturers

to recycle their used products, and for designing less toxic, more recyclable gadgets in the

first place.

The current bottle bills should also be expanded even to other countries. In 2005, 2

million tons of plastic bottles in the United States ended up in the trash instead of in

recycling bins. The State container deposit law which is known as "bottle bills" are long

overdue for an upgrade. They have proven to be the most effective approach to collecting

bottles and cans. Currently, only 11 states have bottle bills in America, and most of them

include only beer and soda bottles but not water bottles, which accounted for 14 percent

of bottled beverages in 2005. Such bill with a higher deposit would give a huge boost to

our bottle recycling rates.

Plastic bags should also be ditched and left completely. EPA has recorded that the United

States consumes about 380 billion plastic bags a year and recycles less than 5 percent of

them. Reusing shopping bags just as is common in some other countries could reduce that

number significantly and prevent billions of plastic bags from ending up in landfills

(Auckman, 2007). It could also prevent them from getting into the ocean, on trees and

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floating by your window. It is necessary to address the plastic problem. San Francisco

banned the use and distribution of plastic bags by grocery stores in 2007. Other stores

around the country are creating incentives for shoppers to reduce plastic bag use, such as

offering cash back for reused bags, selling branded reusable bags and installing in-store

bag drop-off stations to encourage reuse. This is a good strategy for future advancement

in this sector.

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9.1 References:

Ackerman, Frank. (2007). Why Do We Recycle? Markets, Values, and Public Policy.

Iland Press.

Andrady A. L. (2003). Plastics and Environment. New York: Wiley-IEEE.

Baird, Colin (2004) Environmental Chemistry (3rd ed.). New York, W. H. Freeman.

Bary E. A. (2003). Handbook of Plastic Films. London: iSmithers rapra Publishing.

Board E. E. (2007). Plastic Compounding, Masterbatches, PET and Other Plastic

Processing Industries. New Delhi: Engineers India Research In.

Carl A. Zimring (2005). Cash for Your Trash: Scrap Recycling in America. New Jersey:

Rutgers University Press.

Eiri (2007). Handbook of Polymer & Plastic Technology. New Delhi: Engineers India

Research In.

Gehrke R. (2010). Recycling Projects for the Evil Genius. New York: McGraw-Hill

Professional.

Gleick P. H. (2010). Bottled and Sold: The Story Behind our Obsession with Bottled

Water. London: Island Press.

Harper C. A. (2006). Handbook of Plastics Technologies: The Complete Guide to

Properties and Performance. New York: McGraw-Hill Professional.

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Harper C. A. (2002). Handbook of Plastics, Elastomers and Composites. New York:

McGraw-Hill Professional.

Harper C. A. (2000). Modern Plastics Handbook. New York: McGraw-Hill Professional.

Hulse S. (2000). Plastics Product Recycling: A Rapra Industry Analysis Report. London:

iSmithers Rapra Publishing.

Lundquist L. (2000). Life Cycle Engineering of Plastics: Technology, Economy, and the

Environment. New Jersey: Elsevier.

Mantia F. L. (2002). Handbook of Plastics Recycling. London: iSmithers Rapra

Publishing.

Piringer O. G. (2000). Plastic Packaging Materials for Food: Barrier Function, Mass

Transport. Quality Assurance and Legislation. New York: John Wiley and Sons

Porter, Richard. (2002). The economics of waste. Resources for the Future.

Thomas S. & Visakh P. M. (2011). Handbook of Engineering and Speciality

Thermoplastics. New York: John Wiley and Sons.

Tierney, John. (2006). Recycling Is Garbage. The New York Times.

Tukker A. (2002). Plastics Waste: Feedstock Recycling, Chemical Recycling and

incineration. London: Smithers Rapra Publishing.

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