I’m starting to work on several projects involving the demolition of industrial buildings in city neighborhoods to make way for residential redevelopment. It’s really interesting to see neighborhoods slowly transform from sleepy, gray streets with monolithic, windowless buildings into jumbles of apartment buildings and stores and trees and parking lots, and then to see those areas fill up with people over a period of just a few years. There’s a lot of work that goes into turning an industrial property into land that’s suitable for families and children. I thought it would be fun to write a series of blog posts about what happens when an industrial facility is demolished, and later I’ll write about what happens below ground with the soil and groundwater. Copper is probably the most valuable item left in a factory once it’s been shut down. According to the international copper association (2012 World of Copper Factbook), 32% of all copper produced is used in building construction, and another 14% is used in infrastructure like our electrical grid. The remainder is used in equipment, and these days a large amount of copper ends up on printed circuit boards and wiring that goes into our consumer electronics. One of my former professors at Yale, Thomas Graedel, has spent the last few decades tracking down how copper is used through its entire lifecycle, and he estimates that 156 kg of copper is used to support the modern lifestyle of each and every American. He’s published extensively about the flows of copper, accessible here. So where do we find copper in an industrial building? By far, most is found in wiring and plumbing, but we also find copper in central air conditioning systems, elevators, conveyor belts, and architectural elements like roofing and gutters. Any equipment that’s left in an industrial building will also have a small amount of copper, as will any electronics. Copper is one of the first things to be removed from a building before it’s demolished. We typically call in a specialty metals recycler to come and perform this removal, and they will usually provide a quote of what they’ll pay for the copper they are able to recover. As the building is demolished, any remaining copper will be separated and set aside for recycling. I was surprised to learn that there are still a number of facilities in the U.S. who recycle copper, using a variety of techniques to process the materials and then smelting them (heating them to a high temperature) to remove impurities. Like aluminum, copper is very easily recycled without compromising its quality. The facilities that do this are quite complicated, use large amounts of water and energy, and tend to have highly regulated waste management, wastewater, and air permits. The graph below, from the International Copper Study Group, shows our hunger for copper to support all kinds of development activities, and the degree to which secondary (recycled) copper is an important source. While U.S. facilities continue to produce copper for the international market, a large amount of both primary and secondary copper production has shifted to Asia. Is this because environmental requirements are less of a burden there? Or because labor is cheaper? I tend to think it’s a combination of those factors combined with the fact that much of the demand for copper now resides in Asia, where so much primary industrial production is now focused.
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Marty WaltersEnvironmental Scientist Archives
March 2021
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