E Waste Case Study

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- The first method, Market Supply Method A, (MA) assumes that the average life time of an electronic product is approximately 5 years and after that these are discarded and come to the waste stream.

- The second method, Market Supply method B, (MB) assumes that all the products are not disposed at the same time, rather they are disposed in varying quantities over successive years. Here weighted average method is used to show the product disposal trend.

For PCs the growth rate is considered to be 11.4% and for cell phones a 1005 growth rate is considered annually.

Year

Personal computers

Weight (in tons)

Method A

Method B

Average

2010

16,701

13,945

15,323

2011

18,251

16,701

17,476

2012

19,802

16,116

17,959

The quantity of e-waste to be generated from these 2 types of electronic products is shown below

Year

Cell phones

Weight (in tons)

Method A

Method B

Average

2010

2,567

2,824

2,696

2011

5,135

5,135

5,135

2012

7,702

7,702

7,702

Table: Estimation of PC and cell phone waste in Dhaka

Note: 1 Weight of PCs is derived 27.2 kg/PC (Sinha et al.2007).

Note: 2 Weight of cell phones is derived 0.079 kg/cell phone (Pervez et al.2007).

3. The Environmental Impact of electronic waste (e-waste)

From outdated television sets and computers to old cellular phones, VCRs and stereo systems, electronic waste abounds in the industrial world. By some estimates, there are more than 300 million computers that are either obsolete or largely unused in America. Add to that the massive act of television sets made into food waste by the coming of digital TVs and the ever-growing amount of junked phones, MP3 players and numerous other electronic gadgets and the potential for waste is tremendous. Greenpeace has calculated that just one fourth of the total electronic waste is reused or properly processed before getting into a landfill. Rather clearly, electronic waste is non-biodegradable. What is not so well known are the chemicals used in the production of most of this wasteland, when it ends up in landfills or incinerators, the negative environmental impact is severe.

3.1. Chemicals in Electronics and Potential environmental problems related to e-waste

The outside of the most electronics is built of a combination of plastic, glass and sometimes metal. These materials alone should not simply stop up in a landfill. Internally, though, the makeup of electronics consists of numerous chemicals, many of which are carcinogenic. Monitors from computers and television sets as well as the circuit boards contain lead. New flat-panel monitors also contain mercury. Cadmium, a carcinogen, is found in certain batteries. Other hazardous chemicals found in some electronics include zinc, chromium, selenium, arsenic and PCBs or polychlorinated biphenyls. Polyvinyl chloride or PVC as it is commonly known is a product with infinite applications. One of these is insulation of lines and wires used in electronics. The discharge of chlorinated dioxins is a guarantee when these waste products are burned.

The different substances-elements-pollutants related to e-waste are presented in Table 1. Some of them, such as heavy metals, are used in the production of electronic items, while others, such as Polycyclic Aromatic Hydrocarbons (PAHs) are produced by e-waste burning at low temperature. Burning the isolating plastic cover of cables in open barrels produces 100 times more dioxins than domestic waste burning. Considering that the annual e-waste production approximates 20Mt, the total quantities of the several pollutants contained in the e-waste flow result, to a great extent, in landfills or recycling centres affecting the environment and/or public health. Therefore, despite significant recycling, e-waste is liable for 5000 t Cu annually released to the environment. PBDEs (Polybrominated diphenyl ethers) are combustion retardants that finally result in the environment and, given that they are lipophilic compounds, are bio accumulated in living organisms, while the refrigerators and air-conditioners discarded contain CFCs (Chlorofluorocarbons) that will eventually destroy the ozone layer when, in the future, CFCs escape from the e-waste dumping site.

The aforementioned problems grow bigger considering the fact that the majority of e-waste are not recycled, because several electronic and electrical items are discarded along with household waste and are subject to no further treatment. Approximately 80% of the quantity collected for recycling is exported to countries such as China, India, Pakistan, Vietnam, Philippines, Malaysia, Nigeria, Ghana etc. This results in their treatment in very loose environmental frameworks having increased impact on the environment and the employees in the specific operations. Nongovernmental organizations, such as Greenpeace, report this «secret flow».

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Table 1: Potential environmental pollutants produced from e-waste management procedures.

3.2.