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     e-Waste Technologies


    Electronic waste (e-waste) disposal, reuse and re-cycle technologies

    Prof. Dr. Muammer Kaya

    Osmangazi University, Technological Research Centre (TEKAM),

    26480, Eskişehir, Turkey_________________________________________________________


    The purpose of this study is to raise awareness of the large and growing scope of the e-waste prob-lem in the World. Specifically, this study attempts to inform the public, researchers and policy mak-ers regarding the volume and hazards pose by e-waste, the growing financial impact on local gov-ernments and taxpayers for its cleanup. Even though there are conventional disposal methods (such as landfill and incineration) for e-waste, these methods have both economic and environmental dis-advantages; recycling is a new waste management option which diverts end-of-life (EOL) electronics from landfill and incineration [1, 2]. Successful diversion strategy must be based on economic sustai-nability, technical feasibility and social support [3]. Recycling infrastructure, which is not yet estab-lished well in the World, includes transportation, collection, recovery and resale establishments. The first part of this paper describes the e-waste facts, how big is the e-waste problem and existing recycling programmes and collecting methods in the USA and Europe; second part, describes vari-ous methods available to recover valuable materials (glass, plastic and metals ( Cu, Al, Steel, Ni, Au, Pd, Cu etc)) in e-waste for a safe and environmental friendly disposal.

    1 What is e-Waste?

    Since the 1980s, with the development of consumer-oriented electrical and electronic technologies, countless units of electronic equipment have been sold to consumers. E-waste, is the inevitable prod-uct of a technological revolution. When electronic products become obsolete and are ready for dis-posal, they are known as e-waste. Whether generated at our home or at office, e-waste is most rapid-ly growing waste problem in the world. Information technology and electronic industry are the world’s largest and fastest growing manufacturing industries and as a consequences of this alarm-

    ing growth, combined with rapid product obsolescence, discarded electronics is now the fastest growing solid waste stream in the industrialized world. Most of the governments have been forced to respond/solve this serious problem. But to date, industry, government and consumers have only tak-Proceedings of EMC 2007 1


    en small steps to deal with this looming problem. Developed countries that use most of the world’s

    electronic products and generate most of the e-waste, tried to solve the problem by exporting ha-

    zardous e-waste to the developing poor countries of Asia and Africa. 2 Classification of e-Waste

    According to the Waste Electrical and Electronic Equipment (WEEE) directive, e-waste definition,

    classification, recovery, reuse and recycling ratio aims are given in Table 1: Table 1: E-Waste Classification and Recovery, Reuse and Recycling Ratio in WEEE Directives.

    WEEE Category Rate of Recovery Rate of Reuse

    & Recycling

    1. Large household appliances (ovens, refrigerators, 80% 75%

    driers, washing machines, air conditioners etc.)

    2. Small household appliances (toasters, vacuum 70% 50%

    cleaners, mixers, ovens etc.)

    3. IT& telecommunication appliances (PCs, desk 75% 65%

    tops, lap tops, printers, phones, scanners, mouses, fax-

    es, photocopy machines, computer peripherals, wireless

    devices etc.)

    4. Consumer equipments electronics (TVs, flat pa-75% 65%

    nels, plasmas, LCDs, HiFis, portable CD players,

    DVDs, VCDs, iPods, MP3s, PDAs etc.)

    5. Lighting equipments (mainly fluorescent tubes/ 70% 50%

    bulbs) (gas discharge lamp 80%)

    6. Electrical and electronic tools (E-tools) (drilling 70% 50%

    machines, electric lawnmowers etc.)

    7. Toys, leisure & sports equipments (electronic toys 70% 50%

    training machines etc.)

    8. Medical devices (X-Ray, MRI, EKG, SEM, Micro-To be established by end of 2008

    scopes etc)

    70% 50% 9. Monitoring and control instruments (Lasers,

    GPRS etc)

    80% 75% 10. Automatic dispensers (ticket issuing, vending

    machines automats etc.)

3 e-Waste Problem

    E-waste has become a serious problem not only of quantity but also a crisis born from toxic ingre-

    dients (such as Pb, Be, Hg, Cd, Cr and brominated flame retardants (BFRs) which create both occu-

    pational and environmental health threats and hazards. E-waste contains over 1000 different sub-

    2 Proceedings of EMC 2007

     e-Waste Technologies

    stances, many of which are toxic, and creates serious pollution problems upon land filling/burning. Due to the extreme rates of obsolescence, e-waste produces much higher volumes of waste in com-parison to other consumer goods. The life span of a computer has shrunk from five to two years due to rapidly evolving technology. Consumers nowadays rarely take broken equipment to repair shop because replacement is now easier and cheaper than repair. Cathode Ray Tubes (CRTs) in computer monitors, TV sets and video display devices contain significant concentrations of Pb and heavy metals. For these type of hazardous waste disposal to the municipal solid waste (MSW) land-fills is prohibited. Each computer or TV set display contains 2-4 kg of Pb. Monitor glass contains about 20 wt % Pb that protects consumers from X-ray radiation. Consumer electronics already constitute 40% of Pb and about 70% of the heavy metals (Hg and Cd) found in landfills. These heavy metals and other hazardous substances found in electronics can contaminate ground water and pose other environmental and public health risks. Historically, e-waste has been dumped in landfills or burned in incinerators, just like other MSW. It is better to get rid of old electronic devices as soon as it seems to be obsolete. Because stored old e-waste is more difficult to recycle and more toxic and generally does not contain any residual value.

3.1 Some Facts about e-Waste in the World

    * According to the US Environmental Protection Agency (EPA), in 1997 more than 3.2 million tons of e-waste ended up in US landfills. Yearly electronic waste produced in the USA, is esti-mated 5 to 7 million tons. Only 10% of this e-waste is recycled. 30% or more stored typically for 3-5 years for future disposal and the rest is land filled [2]. Electronic waste already constitutes from 2% to 5% of the US MSW stream (more than beverage containers, disposable diapers and about the same level as plastic packaging) and is growing rapidly [4]. In Europe, the volume of e-waste is rising 3% to 5% per year- almost three times faster than the MWS.

    * Today’s computer industry innovates very rapidly, bringing new technologies and “upgrades” to market on average of every 18 months. Conventional TV sets will be replaced by high-definition TVs soon, which will put millions of kilos of Pb/CRT into the environment. According to Stan-ford Research Inc. (SRI) US sales of CRTs used for computer monitors, terminals and worksta-tions equaled 28.4 million units in 2000. Between 1980 and 2005, an estimated 410 to 460 million computer CRTs have been sold in the US. Each year, some 50 million computers and 20 million TVs become obsolete. Approximately 25 million TV sets are sold in the USA annually. Yearly sales have equaled or exceeded 20 million units for the last decade. The use of TVs in US may be double that of computer monitors. But the rate of sales growth (and obsolescence) is slower in TVs than in computers. Annually less than 20000 TV units are being recycled in the USA.

    * In the USA, Americans own about 2 billion electronic devices or 25 per household. Consumers have on average 2 to 3 obsolete computers in their garages, closets, basements, storerooms, attics or storage spaces for later disposal. Americans have buying more computers, than any other na-tions. Currently over 50% of US households own computers. Half of the turned-in computers are in good working conditions but they are replaced with the latest technology.

Proceedings of EMC 2007 3


    * The lifespan of PCs is getting shorter, in 2006 the lifespan of PCs will be 2 years [5]. In the USA, there are 315 to 680 million unused computers. SRI projects that total of nearly 500 million obso-lete computers between 1997 and 2007. Between 1997 and 1999, only 50 million US comput-ers dumped, burned, shipped abroad or stored for disposal. In 1999, NSC reported 11-15% dis-carded computer is recycled compared with 28% of overall MSW and 70% of the major appliances (like refrigerators, washing machines, dryers) recycling in the USA.

    * In EU, 6.5 million tones of e-waste are generated yearly [3]. In USA, between 50% and 80% of the collected e-waste for recycling are not recycled domestically at all, but very quickly placed on container ships bound for destinations like China, India, and Nigeria etc. [3]. India exports 4.5 million PC every year from developed countries.

    * In California alone, over $1.2 billion will be spent for e-waste disposal over the next 5 years. Recycling price of a computer is about $10 to $30 per unit. The cost of properly disposal of TVs or PCs could easily be $25 to $50. [3]. According to the International Association of Electronics Recyclers (IAER), 7000 employees were working and $ 700 million annual revenue were obtained from electronic recycling in the USA in 2003. One hundred thirty million cell phones are retired each year in the USA.

    * According to EPA, approximately 78 to 80 million automotive batteries are consumed and re-placed in the USA, not including those used for large tracks or nonautomotive uses, such as lawn and garden machinery and emergency power and the nationwide recycling rate is about 90%. 80% of the consumed Pb is manufactured by the recycling of old Pb-acid batteries in the secondary smelters. Average battery contains about 9 kilos of lead. Primary Pb industry is declining and na-tional demands are filled by secondary smelters using recycled materials [7].

    * Household battery industry in the USA is estimated to be a $ 2.5 billion industry with annual sales of nearly 3 billion batteries. These batteries are used in over 900 million battery operated devices [8] In 2000, over 75 million NiCd batteries, which are considered one of the most hazardous with respect to disposal, were sold. The battery consumption per person is about 10 in Europe [6]. In Europe 5 billion units of batteries were produced in year 2000 [8]. Zn-C cells represent 39%, alkaline cells 51% and rechargeable batteries represent 8% of European portable household bat-tery market. Among the rechargeable batteries NiCd represents 38%, NiMH 35% and Li-ion 18% of the European market [9]. E-waste market will be expected to generate $ 7.2 billion in 2007 and $11 billion in 2009.

4 Current e-Waste Disposal Methods

    The volume of obsolete electronics thrown out or temporarily stored for later disposal is already a serious problem. Land filling, exporting, re-using and recycling are the currently used processes. The overwhelming majority of the world’s hazardous waste is generated by industrialized market econo-

    mies. Exporting this waste to less developed countries has been one way in which the industrialized world has avoided having to deal with the problem of expensive disposal and close public scrutiny at home. Exporting of e-waste is profitable and cheaper because of labor costs and regulations offshore are lax compared to developed countries law. Shipping monitors (at a price of working $24 and non-4 Proceedings of EMC 2007

     e-Waste Technologies

    working $6 each) to poor countries for reclamation is 10 times cheaper than recycling the same units at home. Due to horrific working conditions and weak labor standards in many developing co