Electronic waste, e-waste, e-scrap, or Waste Electrical and Electronic Equipment (WEEE) describes discarded, obsolete, broken, electrical or electronic devices. Electronic equipments usually contain some very serious contaminants like lead, cadmium, beryllium, and brominated flame retardants. Even in developed countries recycling and disposal of e-waste involves significant risk to workers and communities and great care is needed to avoid unsafe exposure in recycling operations and leaching of material such as heavy metals from landfills and incinerator ashes. It is found that in United States, an estimated 70% of heavy metals in landfills comes from discarded electronics although electronic waste represents only 2% of America's trash in landfills. Trade in electronic waste is controlled by the Basel Convention.. Toxic substances in electronic waste include lead, mercury and cadmium. Carcinogenic substances in electronic waste include polychlorinated biphenyls (PCBs). Extreme cases are also reported where brokers and others calling themselves recyclers export unscreened electronic waste to developing countries, avoiding the expense of processing bad cathode ray tubes which is expensive and difficult. Burning these items in an open fire, releases carcinogens and neurotoxins into the air contributing to an acrid, lingering smog. These noxious fumes are reported to contain dioxins and furans also.
Processing techniques: In developed countries, electronic waste processing first involves dismantling the equipment into various parts (metal frames, power supplies, circuit boards, plastics), often by hand. The advantages of this process are the human's ability to recognize and save working and repairable parts, including chips, transistors, RAM, etc. In an alternative bulk system, a hopper conveys material for shredding into a sophisticated mechanical separator, with screening and granulating machines to separate constituent metal and plastic fractions, which are then sold to smelters or plastics recyclers. The recycling machinery used must be an enclosed one with proper dust collection system. Most of the emissions must be caught using scrubbers and screens. Magnets, eddy currents, and trommel screens are employed to separate glass, plastic, and ferrous and nonferrous metals, which are then further separated in a smelter. Leaded glass from CRTs can be reused in car batteries, ammunition, and lead wheel weights or can be sold to foundries as a fluxing agent in processing raw lead ore. Copper, gold, palladium, silver, and tin are other valuable metals that can be recovered and sold to smelters for recycling. Hazardous smoke and gases evolved during processing needs to be captured, contained, and treated to mitigate environmental threat. These methods if properly followed can ensure proper disposal and safe reclamation of all valuable e-waste.
As per Pollution Control Board notification rule 5 (Prevention & Control of Pollution) and its subsequent amendments with latest amendment on 24th September 2008, by Ministry of Environment and Forests-New Delhi, on "Handling & Disposal of hazardous e-Waste", it is mandatory to dispose-off such lie-Waste" through authorized Pollution Control Board operators, having facilities to handle, collect, store & dispose-off hazardous e-Waste in an environment-friendly manner and as per guidelines issued by the Central Pollution Control Board from time to time.
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