Recycling Minerals
Everyone hears about the importance of recycling paper, glass, and plastic but one area not typically mentioned is the need
to recycle metals also. In fact, anything that has the ability to be recycled should be since most material objects are to
some degree made up of minerals.
Minerals are an unrenewable resource, and at the current rate, minerals are being consumed just as fast as
they are being processed. The increase in consumption began with the industrial revolution (Dasch, 1996).
If a global awareness is not reached about the importance of recycling minerals, then it is possible to deplete the Earth of
her resources and run out of that specific mineral. That would cause society to go back to the waste dump sites to look
for the mineral resources still in high demand at the time (Aber, 2005). Take for example the computer:
By the year 2004, the National Safety Council estimates that more than 315 million computers will become outdated and will be replaced (Environmental Protection Agency, 2002a). If all these computers were to be thrown away in the trash, it is estimated that they would account for 8.5 million tons of waste in the United States alone (Environmental Protection Agency, 2002a). This is of great concern since computer contain dangerous and toxic materials including lead, mercury, cadmium, and other bioaccumulative compounds (Environmental Protection Agency, 2002a).
The average lifespan for a computer in 1997 was 4 to 6 years, and 6 to7 years for the monitor (Environmental Protection Agency, 2002b). With the increase in production of computers, as well as the advancement in technology, these lifespans have decreased by 2 years (Environmental Protection Agency, 2002b). Now, for every one computer that is bought, another computer has just become obsolete (Environmental Protection Agency, 2002b).
In 1999, 24 million computers became outdated and only 14 percent of them were either recycled or donated (Environmental Protection Agency, 2002b). The other 20 million computers were dumped, incinerated, shipped as waste exports, or put into storage. By 1980, over 300 million computer monitors had been sold and by 1997 only 1.7 million had been recycled (Environmental Protection Agency, 2002b).
Obviously, computers are an important product to recycle for its numerous hazardous and useful mineral resources. Currently, households are not required to recycle their computers. The Resource Conservation and Recovery Act require that all business dispose of computers properly since they fall under the definition of hazardous waste (Environmental Protection Agency, 2002a). The Environmental Protection Agency gives a couple of examples of how to properly dispose of a computer:
- Donate it to an organization and use it as a tax-deductible contribution.
- Sell it to a company that buys old computers for recycling. Type “computer recycling” in a web search engine if needed.
- Use a local program that collects household hazardous waste. To find out if the program will take electronic equipment call the local waste hauler. There is information on the web about days when these types of collections are made.
Thus, this example of recycling computers was given to raise your awareness of the non-renewable mineral resources that go into appliances we rely on each day. More examples follow on the importance, practice, efficiency of recycling the native element, gold, and the element lead, which is acquired from the sulfide mineral galena.
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Gold Recycling
Picture taken from Focus on Gold,
www.thegoldpage.com/
golden_facts/focus_on_gold.htm. |
Humans pollute the air in many ways from smoking cigarette to driving a car, but the single most polluting activity done on Earth is mining for gold. According to the Environmental Protection Agency (EPA), mercury pollution from trash incineration, hazardous waste collection, and mercury mining combined still does not add up to half the total amount of mercury pollution made by gold mining (Ingenthron, 2004).
In 1998, an overall recycling rate of 29 percent was reached when consumed scrap was compared to domestic supply (Amey, 2005). Old scrap consists of jewelry, dental materials, plating solutions, electronic equipment etc. and new scrap are usually industrial and is nearly completely recycled or recirculated. The recycling rate for old scrap is at 96 percent which amounted to 175 metric tons (Amey, 2005).
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Not all gold can be recovered from recycled items, for example; it is becoming increasingly difficult to obtain the gold out of electronic products that are becoming more miniaturized. The high percentage of recycling is attributed to the high value placed on the mineral. An estimated 85 percent of all the gold ever mined can be accounted for (Amey, 2005). The missing 15 percent has either been lost or used in some kind of industrial process where it is cannot be readily retrieved (Amey, 2005).
After gold has been mined, approximately 63 percent is used in jewelry (which includes art), 21 percent as coins, 15 percent in some kind of industrial use including electronics, and the other 1 percent in dental (Amey, 2005). Since jewelry and coins are usually kept as collector pieces, family heirlooms, or personal wear, the highest percentage of gold that can be recycled by the average person is in their electronics.
The handling, accountability, and security in the generation, collection, and distribution part of the recycling industries is usually very extensive and elaborate. Many times all items that even come in contact with the gold is also processed to obtain as much of the gold as possible. This includes the gloves, aprons, and dust masks worn by the workers and the tools used to dust or sweep the shops. Even the floors are burned just to recover any gold that may be on them (Amey, 2005).
During the recycling process, any impurities including lead, copper, and silver that are found during the process are gathered into a “sludge” (Amey, 2005). This “sludge” contains all the platinum-group metals, which are recovered through various other methods (Amey, 2005).
The Vermont Recycler Registers have a patent for a method they use in making “100% recycled content” wedding rings from recycled computers. This idea was done to help provide an alternative to mining gold, and to help promote computer recycling (Ingenthron, 2004).
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Lead Recycling
Rough specimen of the lead
mineral. Picture taken from webmineral.com/data/
Lead.shtml, The Mineralogy Database |
Lead is a mineral that has been in use for at least 5,000 years. And the total lead consumption in the United States is 29 percent of the total worlds. In 1998, the lead recycled as a percentage of apparent lead supply was estimated at 63 percent, and recycling efficiency at 95 percent (Smith, 2005).
Domestic demand for refined lead is in for batteries, fuel tanks, seals, solders and wheel weights and in the communication, construction, electrical, and electronic industries in such products as batteries, cable covering, extruded shapes, pipes, and radiation shielding (Smith, 2005). Ceramic, crystal glass, and specialized chemicals also make up a small amount of lead consumption (Smith, 2005). In 1999, North America consumed over 1,000,000 tons of lead just for battery usage (Nova Pb, 2000).
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The leading lead product recycled is lead-acid batteries. In 1998, approximately 88 percent of those batteries were SLI automotive with a lifespan of about 4 years, 8 percent were a motive power type, lifespan of 6 years, and 4 percent were a stationary type, lifespan of 10 years (Smith, 2005). Estimations show that 97 percent of the lead recycled was from lead-acid batteries. The rest was from other metal sources including castings, sheet, solders, and miscellaneous fabrications (Smith, 2005).
Lead is such an important mineral and is so hazardous that roughly 77 percent of refined lead production is from recycled lead (Smith, 2005). This is important to be able to meet the demand of refined lead in the United States (Smith, 2005).
The high recycling rate of the lead-acid batteries is attributed to sales agreements through retailers and battery manufacturers (Smith, 2005). When a person goes in to get a new car battery, the retailer usually keeps the old one and returns it to the original company to be recycled. The loss of lead is very small in the recycling process of the batteries. The EPA regulates the process of recycling lead and any secondary lead smelters are required to significantly restrict the loss of any lead (Smith, 2005).
Computer monitors contain around 4-8 pounds of lead that is encased in glass (Prior, 2005). This lead is there to protect you, but it makes it important for a person to recycle their old monitors. Also, cathode ray tubes (CRTs) are very high in lead content; anything containing a CRT should be recycled such as an old television set (Prior, 2005).
The EPA is now playing a major role in the education and protection of the public in regards to lead. In 1978, 3 to 4 million children had elevated lead blood levels in the United States (Environmental Protection Agency, 2005). By 2002, that number dropped dramatically to only 310,000 children and is continuing to decline (Environmental Protection Agency, 2005). The EPA has already worked to get rid of lead gasoline, lead paint, reduced lead in water and air pollution, and banned or limited lead use in consumer products (Environmental Protection Agency, 2005).
The National Information Center (NLIC) is a program that provides the general public and professionals with information about the prevention and possible hazards caused by lead. For any information, or request materials you can call 1-800-424-LEAD (5323) Monday through Friday, 8:00 am to 6:00 pm eastern time (except Federal holidays) (Environmental Protection Agency, 2005).
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References
- Aber, Susan Ward, 2005. Personal Communication.
- Amey, Earle B., 2005. "Gold Recycling in the United States in 1998": Flow Studies
for Recycling Metal Commoodities in the United States , Scott F. Sibley (ed.), p. 5-15. http://pubs.usgs.gov/circ/2004/1196am/c1196a-m.pdf.
- Dasch, E. Julius, Editor in Chief, 1996. MacMillan Encyclopedia of Earth Sciences. Volume 2.
Simon and Schuster MacMillan, New York, p. 914-915.
- Environmental Protection Agency, 2002a. "Recycling Old Computers". Accessed November, 2005. http://www.epa.gov/region02/r3/compute.htm.
- Environmental Protection Agency, 2002b. "Life Cycle of Old Computers". Accessed November, 2005. http://www.epa.gov/region02/r3/problem.htm.
- Environmental Protection Agency, 2005. "Lead in Paint, Dust, and Soil". Accessed November, 2005. http://www.epa.gov/lead.
- Ingenthron, Robin, 2004. "Gold without Gold Mining? Electronics Recycling Breaks New Ground". PRWeb Press Release.
Accessed November, 2005. p. 1-2. http://pdfserver.emediawire.com/pdfdownload/142436/pr.pdf, pdf File.
- Nova Pb, 2000. "Lead Recycling: Canada's Largest Integrated Lead Recycling Facility". Accessed November 2005.
http://novapb.com/lead_recycling.htm.
- Prior, Carol, 2005. "Recycling Computers". Accessed November, 2005. http://www.mtholyoke.edu/offices/srm/env/recycle/computer.shtml.
- Smith, Gerald R., 2005. "Lead Recycling in the United States in 1998": Flow Studies
for Recycling Metal Commoodities in the United States , Edited by Scott F. Sibley, p. 74-84. http://pubs.usgs.gov/circ/2004/1196am/c1196a-m.pdf, pdf File.
Return to www.emporia.edu/earthsci/amber/go336/webpages.htm, GO 336 Mineralogy student webpages.
© Notice: This Webpage project was created for a
Mineralogy Course in November 2005 at Emporia State University. The assignment
was to learn Webpage creation, as well as present a summary of our knowledge regarding the importance of recycling minerals.
Any other use of text, imagery or curriculum materials is prohibited without permission of the course webmaster,
Susan Ward Aber (2005).
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