Common Metals

Copper

Copper is a very popular metal used in electrical, automotive, household objects, and more recently as an effective antimicrobial surface. Copper makes a very good electrical conductor and is widely used for electrical wiring for homes and buildings as well as electronic equipment.

Almost all of the 700 billion pounds of copper that has been mined to date worldwide is still in circulation. Since 1864, about 66 per cent of all the newly-mined copper consumed in the United States has been returned and reused as scrap. More than three-quarters of the copper produced by copper and brass mills (except for wire production, which requires newly refined copper) comes from recycled scrap copper.


About half of all recycled scrap copper is post-consumer scrap, recovered from things like electric cable, automobile radiators, or air conditioners. The rest is new scrap copper, for example, turnings and chips from screw manufacturing. About 40 percent of all copper used is found in building construction, and about 440 pounds of copper is used in the average single-family house. It is used for building wire, plumbing tube, fillings, and valves, plumbers’ brass goods, built-in appliances, and builders hardware.

Recycled scrap copper provides more than two-thirds of the copper used to make plumbing tube and architectural sheet products. According to the Center for Resourceful Building Technology, located in Missoula, Montana, copper is also one of the most resource-efficient roofing materials available. Copper roofing contains a high percentage of recycled scrap. Copper roofs are also very durable, often lasting 100 years or longer. Historic Christ Church in Philadelphia has the oldest copper roof in the USA, dating back to 1727.

copper-church-roof

Copper used for pipes…

Copper tube is used in direct-exchange geothermal heating and cooling systems. This new energy-saving technology harvests the earth’s natural heat to heat and cool houses and small office buildings efficiently and without use of pollution-causing fossil fuel emissions. The tube is generally made from recycled scrap copper.

Copper kills bacteria!

Copper is also useful in a wide variety of situations where strong chemicals might otherwise be necessary. Zebra mussels are prevented from clogging water intakes in the Great Lakes by copper alloy screens that keep them from attaching to the surfaces, and copper hull sheathing or copper-containing paint on ships protects them from barnacles and other types of biofouling.

Copper is 30 times more effective than stainless steel in stopping bacteria growth. E. Coli and Listeria monocytogenes bacteria die after exposure to copper, as does methicillin-resistant Staphylococcus aureus, the dangerous antibiotic-resistant bacteria. Researchers at the University of Chile are examining copper’s effectiveness against Salmonella enterica and Campylobacter jejuni. It may also kill some viruses, especially those associated with Influenza.

Copper-containing solutions applied to fruits and vegetables can prevent bacterial and fungal infections. Bacteria, such as Salmonellae and Cronobacter sakazakii, often found in food contamination, are rapidly killed on contact with copper alloys. The use of copper will continue to expand and may lead to an increase in mining and production.