| abstract | - The most common metals to consider when discussing recycling are aluminum and steel. Some other metals–like gold, silver, brass, and copper–are so valuable that they are rarely thrown away. They do not create a waste disposal problem. Aluminum and steel do. Americans use 100 million steel cans and 200 million aluminum beverage cans every day. What should we do with this metal waste? Should we burn it in waste-to-energy plant? Should we landfill it? Or should we recycle it? After source reduction (using less aluminum to make a can, for example), recycling is the most efficient way to reduce aluminum and steel waste. Unlike paper and plastics,burning metal trash in waste-to-energy plants creates no energy. Instead, aluminum melts and steel just gets very hot. Magnets can be used to collect steel scrap at waste-to-energy plants, though, and then the scrap can be shipped to steel plants for recycling. Landfilling is usually not a good alternative either. Aluminum, in particular, is so valuable as a scrap material that it simply does not make sense to bury it.
- Some other metals, such as Al , Au , Ag , brass, and CUM, are so valuable that they are rarely thrown away. They do not create a waste disposal problem. Aluminum and steel do. Americans use 100 million steel cans and 200 million aluminum beverage cans every day (a total of 300,000,000 metal cans). What should we do with this metal waste? Should we burn it in waste-to-energy plant? Should we landfill it? Or should we recycle it? After source reduction (using less aluminum to make a can, for example), recycling is the most efficient way to reduce aluminum and steel waste. Unlike paper and plastics, burning metal trash in waste-to-energy plants creates no energy. Instead, aluminum melts and steel just gets very hot. Magnets can be used to collect steel scrap at waste-to-energy plants, though, and then the scrap can be shipped to steel plants for recycling. Landfilling is usually not a good alternative either. Aluminum, in particular, is so valuable as a scrap material that it simply does not make sense to bury it. this saves 155% of energy and 95% of air pollution Scrap metal includes ferrous metals (Fe and steel) and nonferrous materials (Al , Cu , Sn , brass). Many of our home appliances are made of metals. This includes our washers & dryers, refrigerators, ovens & stoves and water heaters. Waste from unwanted appliances can be categorized in two main types: refrigerants (Freon) and non-refrigerants. The recycling process for metal is similar to those of other materials. It is best described in four stages: 1.
* Collection 2.
* Processing 3.
* Shredding 4.
* Selling After collection and proper sorting, the scrap is compacted. It is then sold to minimills, which process them to steel. According to RecycleMetal.org, “processing scrap metal to steel instead of virgin ore require about 74 percent less energy.” 1.
* Cans are first divided from municipal waste, usually through an eddy current separator, and cut into little, equal pieces to lessen the volume and make it easier for the machines that separate them. 2.
* Pieces are cleaned chemically/mechanically, and blocked to minimise oxidation losses when melted. (The surface of metal readily oxidizes back into metal oxide when exposed to O .). 1.
* Blocks are loaded into the furnace and heated to 2800 °F to produce molten metal. 2.
* Dross is removed and the dissolved H is degassed. (Molten metal readily disassociates hydrogen from water vapor and hydrocarbon contaminants.) This is typically done with Cl and nitrogen gas. Hexachloroethane tablets are normally used as the source for Cl . Ammonium perchlorate can also be used, as it decomposes mainly into Cl , N , and O when heated. 1.
* Samples are taken for spectroscopic analysis. Depending on the final product desired, high purity metal, Cu , Zn , , Si , and/or is added to alter the molten composition to the proper alloy specification. The top 5 metal alloys produced are apparently 6061, 7075, 1100, 6063, and 2024. 1.
* The furnace is tapped, the molten metal poured out, and the process is repeated again for the next batch. Depending on the end product it may be cast into ingots, billets, or rods, formed into large slabs for rolling, atomized into powder, sent to an extruder, or transported in its molten state to manufacturing facilities for further processing.
* Have the delivery company for your new appliance, take the old with them. These companies can either recycle the unit or properly dispose of it
* Have a professional disassemble your appliance and take the appropriate materials to recyclers in your area
* If the appliance is still working, sell it on online, donate it to ta charity or give it to a friend recycling one ton of metal could save 5/4 tons of iron ore, 1,000 pounds of coal, 278 pounds of limestone, a 465/2 cubic meter lake (2/5 of H2O ), enough energy to light a 60 watt light bulb for 1,300/219 years, a CFL for 49,826,951/292,000 years, power over 493/2,000 cars for a year, 3,214,642 KWh of energy (37/50 of energy), a 489/80 cubic meter container of oil, 248,500,000 Btu's of energy (37/50 of energy), 14 cubic yards of landfill space, the equivalent of a 999/160 cubic meter tank of gasoline, 329/200 tons of red mud, 4,383/1,000 tons of bauxite, 1,020 pounds of petroleum coke, 966 pounds of soda ash, 327 Pounds of pitch, 29/20 tons of CO2 , 81 pounds of air pollution (reduced by 43/50), 789 pounds of solid waste, Reduce water pollution by 19/25, enough oil to run the average car for 24,450 miles or circle the globe almost 1,825,600 times, a 48,900,000 cubic meter lake from being polluted, and keep 800 pounds of airborne Hg , 3,600,000 tons of cyanide out of landfills, 806/73 metric tons of coal, 35,464/1,095 metric tons of CO2 , 6,520 acres of soil from being polluted, 80 pounds of fly ash, 403,000/5,037 tons of steam, 9,949,407/9,232 tons of biomass, 100 pounds of SO2 , 750 pounds of coke, 20,375/13 metric tons of global warming, 50 pounds of S , 6,595,153/2,159 tons of acid rain, 333/2 kilograms of benzene, 12,425/969 tons of NH3 , 497/38 tons of methanol, 333/20 tons of climate change, almost 4,401/280 tons of hydrocarbons, a 7,455/1,072 cubic meter container of kerosene, and enough energy to power a 100-watt light bulb for 2,480/73 years, a TV for 300/73 years or a computer for 650/219 years, $396,548.04, gain 6,993/400 tons of O recycling one metric ton of metal could save up to 8 metric tons of bauxite, over 777 pounds of CO2 a year, 400 metric tons of Pb , 4 metric tons of chemical products, 14,000 kwh of energy, over 11 metric tons of greenhouse gases, 12,950/229 gallons of oil, enough energy to power a 21/2 bedroom house for an entire year, and over 13,209/200,000 cars for a year, a CFL for 39,613/3,796 Years, one car to travel 194,250/229 miles, 777/2 power strips, save 11/10 metric tons of iron ore, 630 kilograms of coal, 55 kilograms of limestone, keep 4,599/201,500 tons of Hg out of landfills a year, 7,392/5 square meters of natural habitat potential, 105/23 tons of steam, 51,800/229 acres of soil from being polluted, enough energy to power a 100-watt light bulb for 126/65 years, a tv for 21/130 years, 6,201/61,180,745 metric tons of fossil fuels, 14/39 metric tons of H , 1,043/400 tons of C , 2,772/625 metric tons of life, 1,309/25,000 metric tons of solid particles
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