CASE 5 [27]: Xerox Corporation Site recycling programs, including the conversion of solid waste to useable energy through incineration, saved Xerox over $12 million in 1995. Xerox implemented a plastic recycling program. High-grade plastic panels from returned Xerox products are collected, sorted, disassembled, and ground for reprocessing. The plastic is then used to manufacture Xerox products or is sold to other manufacturers who use plastic. The program has already diverted 250 tons of plastic from landfill in Monroe County and 1996 estimates project 500 tons diverted with $100,000 in savings to Xerox. It also provides a valuable service to users who do not know what else to do with spent toner cartridges. Recycling techniques are classified by the kind of material being recycled: food, fuel, or raw materials. Agro-industrial waste can be converted to food. Coconut presscake7, peanut presscake, and some soybean wastes are used to prepare nutritious food in Indonesia. In Taiwan, growing common mushrooms on composted rice straws has become a multimillion-dollar business. Mushrooms can also be grown on sawdust, cotton waste, bagasse, shredded paper, and banana leaves. Wastes can also be used for animal feed. Different kinds of algae, straws, or crop residues can be turned into feed with simple chemical treatments. CASE 6 [27]: The 3M Corporation In 1990, 3M began a major waste reduction effort. By 3M’s definition, waste is what remains after raw materials are converted to products and by-products. In 1993, resource recovery activities in the U.S. recovered and sold almost 199 million pounds of paper, plastics, solvents, metals, and other by-products. Since 1989, 3M realized more than $156 million by reclaiming and finding buyers for manufacturing waste. For example, employees at a 3M plant in Brazil developed a waste reduction program, sold $150,000 in waste materials, and reduced waste disposal costs by $90,000. Waste materials can be used as fuel in various ways depending on composition, density, heating value, and other properties of the waste. Fuel can be extracted in liquid, gaseous, and solid form. For example, a ton of wheat straw, heated to 500-600 C can yield about 300kg of char, 38 liters of tarry liquid and 280 m3 of gas (15, 000 kj/m3). Raw materials' recycling is widely pursued. Some examples are: • Old tires can be recycled into a useful component for road asphalt. • Aluminum waste from manufacturing processes can be recycled into beverage cans. Glass from bottles can be recycled into new containers and glass pellets to be embedded in other composite materials. Newspapers and magazines can be turned back into pulp to make new paper.
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