plastic waste management 226 a perspective

PLASTIC WASTE MANAGEMENT – A PERSPECTIVE

Professor I. M. Mishra Department of Chemical Engineering

Indian Institute of Technology, Roorkee Roorkee – 247667, India

Email: [email protected] Plastics are polymers which solidify at normal temperature and pressure and are non-soluble in water. They are light weight plastics 1/6 of steel, 1 /2of Al. TYPES OF PLASTICS: (1) Thermoplastics Polyethylene, polystyrene, polyethylene tetrapthalate, plolypropylene, polyvinyl chloride (PVC), ABS, PPMA,(acrylonitrile-butadicane-styrene), asetas, acrylics, celluloses, fluropolymers, nylons, polycarbonates, thermoplastic polyester. May soften or even melt at < 93 °C. Polystyrene cup heated and reshaped into a new form asa dish > 80% of plastc production is thermoplasitcs. (2) Thermosets Products tolerate upto 260 °C phenolics, epoxy resins, thermosetting plastics, polyurethane, < 15% of plastics production. They set or harden, if the heating continuous. The molecules of the plastics link together between cross-linked chains and can not be resoftened through heating. Plastic behaviour of polymers influenced by morphology or rearrangement of molecule on a large scale. Most thermosets are amorphous, while thermoplastics are crystalline Plastics are so versatile in use that their impacts on the environment are extremely wide ranging. Careless disposal of plastic bags chokes drains, blocks the porosity of the soil and causes problems for groundwater recharge. Plastic disturbs the soil microbe activity, and once ingested, can kill animals. Plastic bags can also contaminate foodstuffs due to leaching of toxic dyes and transfer of pathogens. In fact, a major portion of the plastic bags i.e. approximately 60-80% of the plastic waste generated in India is collected and segregated to be recycled. The rest remains strewn on the ground, littered around in open drains, or in unmanaged garbage dumps. PET: IDEAL PHARMA PACKAGING MATERIAL: Researchers worldwide have given a new dimension to pharmaceutical packaging in the form of polyethylene terphthalate or PET, which was previously used for packaging of beverages and mineral water. According to World Health Organization (WHO), norms for pharma packaging of containers should protect the drug from water vapor, gases or light; any reaction between container and drug should remain below a level that adversely affect the safety, stability, or efficacy of drugs. PET appears a clear choice over glass due to its superior physical and chemical properties.

PLASTIC INDUSTRY PROFILE The Plastics Industry in India has made significant achievements ever since it made a modest but promising beginning by commencing production of Polystyrene in 1957. The chronology of manufacture of polymers in India can be summarized as under: -

• 1957-Polystyrene • 1959-LDPE • 1961-PVC • 1968- HDPE • 1978-Polypropylene

The Plastic Industry in India is growing at the rate of 17% way above the GDP of the country (Government of India [GOI] 1997). PLASTIC WASTE PROBLEMS SPECIFIC TO INDIA Child Labour Indian collection sector employ children below the age of 15 to collect them because of the low wages to be paid to the child and the ease of availability of child labour. Backyard Smelters Backyard smelters and plastic recycling units dot India's suburban/urban sites, taking lead battery scrap and plastic waste imported from developed countries such as Australia and the United States. Copying Western Practices Indians have adopted the consumption pattern of the west. But they have not adopted the disposal practices of the west. Import of Waste India is a good ground for recycling of plastic waste. Economically good as recycling is a lucrative business but India lacks the technology and effective monitoring system to have a controlled process-taking place. The current situation is that the recycling in the country

is creating more problems and with the influx of waste import it is aggravating the problem. If imported, India should also import technology along with the waste. HARMFUL SUBSTANCES RELATED TO THE PLASTIC CYCLE

Benzene - a colourless and highly flammable liquid used as a solvent in the production of PVC and LDPE and as a raw material for styrene. A recognised human carcinogen that causes leukaemia and, in case of direct exposure at the workplace, depresses the central nervous system, causing headaches and other irritations; Cadmium - used as pigments in PET, LDPE, HDPE, PP, PP and other plastics and is a suspected human carcinogen. In the past it was used as a stabiliser of PVC, but this function has been replaced by zinc; Dioxins - highly toxic by-product of the production and incineration of some plastics such as PVC, which may cause abnormalities in the male and female reproductive systems, learning disabilities, different cancerous growth, leukaemia and other diseases; Vinyl chloride - a colourless, odourless gas about twice as dense as air, used as monomer for PVC and is known as a human carcinogen. Mortality data of workers in VC and PVC plants indicate shorter life spans and increased liver and other diseases.

DIOXINS AND FURANS : "Dioxins and Furans" refer to a group of chemical compounds that share certain similar chemical structures and biological characteristics. “Dioxins and Furans” are an unwanted byproduct of combustion, both from natural sources like forest fires and from man-made sources like power plants, backyard burn barrels and industrial processes. There are 210 different dioxins and furans. All dioxins have the same basic chemical "skeleton", and they all have chlorine atoms as part of their make-up. These substances vary widely in toxicity Chemical names and examples are;

• Polychlorinated dibenzo-p-dioxins (PCDDs, dioxins) 2,3,7,8- tetrachlorodibenzo-para-dioxin (TCDD).

• Polychlorinated dibenzofurans (PCDFs, furans).

SOURCES OF DIOXIN AND FURANS CONTAMINATION: Found in all media like air, soil, water, sediment, and food, especially dairy products, meat, fish and shellfish. The highest levels of these compounds are found in some soils, sediments and animals. Very low levels are found in water and air. Main sources of Dioxin and Furans production are by activities like the production of iron and steel, Backyard burning of household waste, especially plastics combustion of wastes (including medical and hazardous wastes), Fuel burning, including diesel fuel and fuel for agricultural purposes and home heating wood burning, especially if the wood has been

chemically treated , Electrical power generation , Exhaust emissions from vehicles, controlled burn-offs, uncontrolled and accidental fires (including landfill fires). Waste Plastics

• 50% from factories as specific plastics ,Polyolefins, PS, PET, PVC • Thermal Decomposition: Incineration, a useful method ,PVC

during incineration, fires or recycling procedures produces HCl, dioxins and chlorinated aliphatic and aromatic compounds at higher temperatures (Kaminsky, 1992),

Pyrolysis, an alternative to incineration (Kaminsky, 1992; Plassmann & Schock, 1996). Additive like carbon black (strength and to increase bulk of rubber) affects thermal decomposition, Butyl rubber ~95-98% isobutylene, and rest butadiene or isoprene. (Low permeability, so in tires , other rubber goods). Carbon black used in thermoplastic polymers in construction industry.It enhances UV stability, electrical conductivity or weather resistance of polymers/plastics, and modifies mechanical properties. PE pipelines, polypropylene geotextiles use carbon black. In PP Geotextiles to enhance soil reinforcement & filtration. Carbon black (CB) as an additive from partial combustion of liquid or gaseous HCs. Polyaromatic structure containing various oxygen-functional groups, so it has free radical scavenging capabilities. Pyrolysis for recycling of polymeric wastes producing chemical feedstocks and carboneous materials TG/DTG behaviour. UV stability related to the type and particle size of CB as well as to the concentration and dispersion in polymer matrix. Pyrolysis of PE, PP, PVC, PS: CB promotes decomposition of PP, but hinders that of PE, PP, PAN. Char yield of PAN is increased considerably. However, no impact on the amount of residue of non-char forming polymers.

Fig.: Thermogravimetric curves (TG and DTG and the evolution profiles of the main products of carbon black FW 200 ( Akab and Omastova, 2005)

Fig.: DTG curves fo PE and PE/30% carbon black SC-72 composite. The DTG curve of the composite is normalized for the mass of PE ( Akab and Omastova, 2005) CB influences through the chain cleavage and H-transfer reactions. Chain scission reactions indicated by lower decomposition temperature and increased formation of products from primary macroradicals. Participates in termination of chain reactions, so digomers yield reduced significantly for vinyl polymers. (Jakab & Blazso, ) J. Analyst & Appl. Pyrolysis.

Tertiary radicals formed during unzipping reaction monomers Primary radicals participate in H- transfer and β-scission reaction → various oligomeric products.

Kinetics of decomposition of polymers: Overall rate = n = apparent reaction order. Table: Rate coefficients apparent activation energies for the thermal decomposition of different plasitcs according to a rate expression (Bockhorn et al., 1999)

Fig. Calculated degree of conversion for batch wise decomposition of a mixture of PVC, PS and PE at various temperatures in stepwise low temperature pyrolysis (Bockhorn et al., 1999, Chem. Eng. Sci.)

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PET bottles: Waste: - PTA+EG → PET - Degraded by steam hydrolysis in the presence of FeOOH, Fe2O3, Ni (OH)2, NiO

as catalyst - giving pure perephthalic acid (PTA) & < 1% carbonaceous residue - PTA recycled for polymer resin synthesis - PTA – a sublimate material (sublimation point ~ 573 K) produced from PET

thermal decomposition. PTA precipitates as a hard solid body around values and pipelines where T < 573 K.

So degrade PET without production of PTA, and convert PTA into useful liquid HCs – acetophenon, benzene, phenol, CO2, other gases and liquids. No benzoic acid (which is sublimate): use FeOOH or Fe2O3. (Masuda et al., 61 (1998) 217, Polymer Degradation and stability). Under the Basel Convention Wastes are substances or objects which are disposed of or are intended to be disposed of or are required to be disposed of by the provisions of national law. ANNEX VIII wastes – hazardous A1180: " Waste electrical and electronic assemblies or scrap containing components such as accumulators and other batteries … mercury switches, glass from cathode ray tubes and other activated glass and PCB-capacitors, or contaminated with Annex I constituents (eg cadmium, mercury, lead, PCBs) " ANNEX IX wastes - covered by the Convention if they contain Annex I constituents and exhibit Annex III hazardous characteristics. B1110: "Electrical and electronic assemblies (including printed circuit boards, electronic components and wires) destined for reuse . E-wastes: the size of the challenge Wide range of products and equipment (suggesting the need to focus action), 1-3 percent of all municipal solid waste more than disposable diapers more than all beverage containers about the same as all plastic packaging increasing 3-5 percent per annum. 3x the increase in the general waste stream rapid obsolescence of many e-products.

• Technological innovation • Marketing of newer models • 50-80% e-waste collected in USA is exported, mainly to Asia (BAN)

E-WASTES: PHONES AND PCS Mobile Phones - 1.5 billion units worldwide - Increasing at 500 million p.a. - Average life span (1st life) - Worldwide 1.3 years - Developing world 2 years - Developed world 0.8 years

Computers

• 1.5 billion PCs worldwide • Global production 150 million p.a. • Average life span (1st life) • Developed world 1.9 years • 315 million ‘obsolete’ PCs in USA alone (US NSC) • Global market for used IT equipment US$9billion (2001) (Kuehr &

Williams) A computer as a waste

It uses 23% plastics of whole consumption of plastics worldwide. Lead – used in solder and for 32% ferrous metals radiation shielding 18% non-ferrous metals

Cadmium – used in batteries 12% electronic boards Antimony – used as a flame gold retardant, chip encapsulate and a palladium melting agent in CRT glass silver. Beryllium – used in connectors in platinum older PCs, Chromium – used in metal plating

Mercury – used in bulbs that illuminate flat screens

BRIDGING THE DIGITAL DIVIDE Exporting good used PCs to developing countries may bring social and economic development and opportunities to the developing world at a reduced cost. This may be a better use of the energy and materials if export is not a waste, if generator of waste can prove it is not hazardous. If importer can prove it can handle the import in an environmentally sound manner? This may be exporting an eventual waste liability to developing countries ‘Ban Amendment’ to the Basel Convention Mobile Phone Partnership Initiative (MPPI) Launched December 2002 Alcatel, LG , Matsushita/Panasonic, Mitsubishi , Motorola , NEC, Nokia, Philips, Samsung, Sharp, Siemens, Sony Ericsson, Vodafone

• Achieve better product stewardship • Influence consumer behaviour • Promote best refurbishing / recycling / disposal options • Mobilise political / insitutional support • Result in an initiative that can be replicated to build • new public/private partnerships

e2e: Global Partnership on Computing & the Environment Launched in October 2004 at 7th Conference of the Parties to the Basel Convention Preparatory meeting - New York 4 June 2004 Discussions with

� Dell, hewlett-packard,ibm, intel, � Microsoft, sony � Noranda, Umicore � Basel Action Network, International Business Leaders Forum Digital

Partnership, International Precious Metals Institute, Electronic Industries Alliance

� UN Global Compact, UNU, UNEP DTIE, UNCTAD � China, EC, France, Japan, Mexico, Netherlands, Switzerland, USA

Next steps

� Draft declaration, work plan, budget � Need for more Asian companies and leadership from Asian

countries

PARTNERSHIP PROJECT GROUPS (MOBILE PHONES) Reuse of used mobile phones Project 1.1 Development of guidelines for refurbishment and for refurbished mobile phones to re-enter the market Collection & transboundary movement Project 2.1 Best practice guidelines for collection schemes and transboundary movement of used phones Project 2.2 Trial of Implementation of collection and treatment Scheme Recovery & recycling Project 3.1 Identification of existing best environmentally sound practices for recovery and recycling of mobile phones Awareness raising & training Project 4.1 Awareness raising and training E-WASTES: SITUATION IN INDIA:

� Imports regularly coming to the recycling markets. � Domestic e-waste, growing exponentially in volumes. � Increases in demand for PCs with penetration density in India � 2 million PCs 486 or below (obsolete) � Inhuman working conditions for recycling.

HW (MH) Rules, 1989 • Sl. No. 31 of Schedule 1 of the rules deals with the residues and wastes generated

from the operation in electronic industry. • Categories A-1180; B-1110 in Schedule 3 C over the import & export of

hazardous wastes- cover electrical and electronic assemblies. • Import of wastes only for direct reuse and not for recycling or final disposal • CPCB preparing ‘Guidelines for Environmentally Sound Recycling of E-waste” • CPCB permitted two e-waste recyclers in the country • Bangalore based E-Parisaars (~ 600 tpy) & Chennai based Trishiraya (~ 350 tpy). • Informal recyclers: Burn PCBs; acid treat PVC wires and break open the cabinet

and ePVs. • To extract gold, silver, platinum, copper etc. • Ash Recyclers (of Syed Hussain) authorized by KSPCB.

E-WASTE GENERATED IN INDIA

1. Mumbai ~ 12500 tonnes/Y 2. Delhi ~ 10500 3. Bangalore ~ 6000

4. Chennai ~ 5200 5. Kolkata ~ 4600 6. Ahmadabad ~ 3700 7. Hyderabad ~ 3500 8. Pune ~ 3000 9. Surat ~ 2200

WIPRO’S PLANS: Aim: Compliance with European Restriction of Hazardous Wubstances (RoHS) due to reach ~ 2,50,000 units PCs by 2007-08, 1,70,000 units in 2006-07 and to phase out the uses of brominated flame retardants (BFR) & PVC. WEEE Plastics recovery & recycling is problematic: Dismantling of cathode ray tube (CRT) glass recovery; & bulk plastics. WEEE contains >10 different polymer types, hazardous organic & inorganic compounds, brominated flame retardants including polybrominated diphenyl ethers (PBDE) and polybrominated biphenyls (PBB): These are restucted & regulated compounds. Some BFRs from highly toxic brominated dioxins and furans (PBDD/F) under thermal stress. Now BFRs with minimized PBDD/F building potential, e.g. TBBPA, oligomeric BFR and improved Deca BDE. so WEEE polymer composition is changing. • Housing materials have polymer blends containing polymers with inherent-

inflammability as poly phenylene oxide or polycarbonate. (Schlammer et al., Chemosphere, 67 (2007), 1866-1876).

UN-Led Alliance of Private & Public Agencies Launched in March 2007: StEP (Solving the E-waste Problem) - Loop hole in Basal Convention: to allow export of hazardous waste to developing

countries if it is to be recycled. - This exploits the cheap labour of developing world to manage the world’s

hazardous waste. Prime Objectives: Optimizing the life cycle of electric and electronic equipment by improving supply chains closing material loops reducing contamination increasing utilization of resources and reuse of equipment exercising concern about disparities such as the digital divide between the industrializing and industrialized countries increasing public, scientific and business knowledge analysis of national legislation and the international framework for controlling, enforcement of trade and enhancing recycling of e-waste and used electronic products evaluation of present approaches of industrializing regions such as Africa, Eastern Europe, Latin America and South-East Asia (including China and India) setting up dialogues with key players in the field of e-waste pointing out existing business models and developing new ones to support the sustainable use of information and communication technologies examining alternatives to existing practice that are more suitable to the situation in the industrializing world recommendation of new types of policy measures.

E-WASTE RECYCLING AREAS IN DELHI WITH SPECIFIC FUNC TIONS

OUTRIGHT IDEAS TO MANAGE THE PLASTIC WASTE

• Ban plastics outright. • Bury them in landfills. • Burn them in municipal incinerators. • Pyrolyze them to industrial chemicals. • Recycle them to useful products.

OPTIONS TO REDUCE THE IMPACTS OF POST-CONSUMER PLASTICS WASTES

1. Source Reduction 2. Recycling 3. Degradable Plastics 4. Additional Efforts to Mitigate Impacts of Plastic Waste

RECYCLING OF WASTE PLASTICS

1. Recycling as blast furnace feed material (chemical recycling) 2. Blast furnace feeding of PVC by removing chlorine 3. Recycling of waste PET bottles 4. Recycling of used electrical appliances

LOCATION

COMPONENT RECYCLED

Turkman gate

Disassembly of Computer, CRT Breaking

Mayapuri

Disassembly of every kind of electrical goods, open and drum wire burning

Old Seelampur

Market of every kind of electrical scrap

Shastri park

Computer Dismanting, recharging of CRTs

Lajpat Nagar

Disassembly of computer

Kirti Nagar

Mainframe Computer disassembling

Mustafabad

Lead recovery

Meerut (near Delhi)

Gold recovery

Ferozabad (near Delhi)

Glass recovery

RECYCLING OF WASTE PET BOTTLES INTO PET RESIN FLAKE S

• Waste PET bottles collected by municipalities contain colored bottles, caps, and labels. The most important issue in this operation is how to remove these foreign objects efficiently and accurately.

• Recycled PET flakes were mainly used for producing fibers for cushion materials and heat-insulating materials, and plastic sheets.

RECYCLING OF USED ELECTRICAL APPLIANCES

• Refrigerant fluorocarbon is recovered from refrigerators and air conditioners using the fluorocarbon recovery device.

• The mechanical crushing & sorting process is composed of the conventional crusher used for processing large wastes, wind sorting machine, magnetic sorting machine, nonferrous metal sorting machine, urethane compressing machine, and heat-insulating fluorocarbon recovery device.

• In the used television processing yard, circuit boards and cables are recovered, and TV tubes are separated from housings.

• Housings made of plastics are utilized as blast furnace feed material. • TV tubes are transported to a company which specializes in processing them

into cullet, which is recycled into new TV tubes by TV tube makers DEGRADABLE PLASTICS Areas of concern regarding degradable plastics

• Is the polymer itself more toxic than degraded product • Are the byproducts of the toxic due to its enhanced degradability? • Does the degradation process increase the leachability of additives from the

polymers? • Do the physical byproducts (i.e., the small pieces of undegraded plastic) pose

a threat to wildlife? BIODEGRADABLE PLASTICS

• Another biodegradable plastic product is a plant pot produced by injection moulding. Gardeners and farmers can place potted plants directly into the ground, and forget them. The pots will break down to carbon dioxide and water, eliminating double handling and recycling of conventional plastic containers.

• Depending on the application, scientists can alter polymer mixes to enhance the

properties of the final product. For example, an almost pure starch product will dissolve upon contact with water and then biodegrade rapidly. By blending quantities of other biodegradable plastics into the starch, scientists can make a

waterproof product that degrades within 4 weeks after it has been buried in the soil or composted.

BIODEGRADABLE PLASTICS

• One of the big impediments to composting our organic waste is that it is so mixed up with non-degradable plastic packaging that it is uneconomic to separate them. Consequently, the entire mixed waste-stream ends up in landfill.

• By ensuring that biodegradable plastics are used to package all our organic

produce, it may well be possible in the near future to set up large-scale composting lines in which packaging and the material it contains can be composted as one. The resulting compost could be channeled into plant production, which in turn might be redirected into growing the starch to produce more biodegradable plastics.

INDIAN REGULATIONS:

• HP Non–Biodegradable Garbage Control Act in 1995. • The Plastic Waste Management Task Force was formed in 1996.

o Formulate a strategy and prepare an action programme for managing plastic waste.

o Propose incentives and penalties to check the growth of plastic packaging waste.

o Prepare guidelines for the use of plastic packaging in the country. (GOI, 1997)

o The Task Force came up with a 14-point action programme. Although all of these 14-point recommendations are yet to be implemented, the Guidelines on Plastic Packaging and Guidelines for Recycling of Plastics were formulated by the Ministry of Environment and Forest and the Bureau of Indian Standards.

o Recycled Plastic Manufacture and Usage Rule (1999) RECYCLED PLASTIC MANUFACTURE AND USAGE RULE (1999) This rule addresses the issue of plastic bag.

• The Rule prohibits the usage of carry bags and containers made of recycled plastic bags for storing, carrying and dispensing or packaging of foodstuffs.

• Mandates the use of only virgin bags of 20 microns of natural colour without any dyes and pigments for packaging foodstuffs.

• The Rule specifies minimum thickness of the carry bags for virgin to be 20 microns and recycled to 25 microns and calls for the producer of the plastic product to mark the product as stated in the Guidelines for Recycling of plastics. It also allows the use of recycled poly bags of a minimum thickness

of 25 microns for non-food applications provided the dyes and pigments used conform to the specification in the Food Adulteration Act.

• The Rule calls for recycling of plastics to be carried out according to the Guidelines for Recycling of Plastics

RECYCLED PLASTICS USAGE RULES, 1998

In exercise of the powers conferred by clause (viii) of sub-section (2) of section 3 read with section 25 of the Environment (Protection) Act, 1986 (29 of 1986), the following draft rules are hereby published for the information of all persons likely to be affected: 1. Short Title. - These rules may be called Re-cycled Plastics Usage Rules, 1998. 2. Prohibition of usage of carry bags made of re-cycled plastics. - No person shall use, carry bags or containers made of re-cycled plastics for storing, carrying and packing the food stuffs. 3. Condition of usage of carry bags etc. - Subject to the provisions of rule 2, any person may use carry bags or containers made of re-cycled plastics if the following conditions are satisfied, namely : - (a) carry bags and containers made of recycled plastics conform to the specifications mentioned in the Prevention of Food and Adulteration Act, 1954 and the rules made there under; (b) Such carry bags and containers are not pigmented : (c) The minimum thickness of carry bags made of recycled plastics shall not be less than 25 microns; and (d) reprocessing or recycling of plastics is undertaken strictly in accordance with the Indian Standards, IS 14534 :1998 entitled " Guidelines for Recycling of Plastics" published by the Bureau of Indian Standards and the end product made out of recycled plastics is marked as "recycled" along-with the indication of the percentage of use of recycled material. 4. The minimum thickness of carry bags made of virgin plastic shall not be less than 20 microns. 5. Prescribed authority: The Government of every State and Union Territory shall notify a prescribed authority with such members as may be specified within one month from the date of coming into force of the final rule, for implementing these rules

PLASTIC WASTE RECOVERY AND RECYCLING- AGENTS INVOLV ED: Formal (municipal) sector The municipality derives its funds for waste management either through funds designated by the Central Government and funds derived from property taxes. Informal sector

• Wastepickers • Kabariwala/Raddiwala • Scrap Dealers • Bulk Buyers

REGULATION AND LEGISLATION: PRESENT STATUS

• The Prevention of Food Adulteration Department of the Government of India has issued directives of various catering establishments to use only food-grade plastics, while selling or serving food items. Rules have specified use of 'food-grade' plastics, which meet certain essential requirements and are considered safe, when in contact with food. The intention is to preventing possible contamination, and to avert the danger from use of recycled plastics.

• The scheme announced in February, 1995, is being implemented in cooperation with the Bureau of Indian Standards (BIS) which has formulated a series of standards on this subject. The Bureau of Indian Standards Sub-Committee PCD 12:1& is charged with formulating guidelines, codes and specifications for recycling of plastics. Two documents viz. 'Guidelines for Recycling of Plastics', and 'Recycled Plastics for manufacturing of products - Designation' have been finalized by BIS. These two documents, together with the 'Guideline on Plastics Packaging and Packaging Waste' are to be implemented by the industry