FACTS & FIGURES — Recycled copper good as new

For some, the term “scrap” may conjure visions of worn-out, useless material. In the case of copper and its alloys, however, this could not be further from reality.

The inherent capabilities of modern smelting and refining guarantee that copper cathode originating from scrap, or from recycled copper, will have the same quality as that originating from primary ores.

Copper is not only the first metal to be employed for tools and weapons; it is also the first to be routinely recycled. Today, recycled copper is conservatively estimated to account for more than 40% of copper consumed annually.

Most copper consumption is used in long-term consumer goods such as wire, cable and plumbing tube, fittings and fixtures. Moreover, it is recycled only after many years — or even decades — of service.

Service life for copper is estimated as 8-10 years in autos, 30-40 years for wire and cable, and 60-80 years in buildings. Eventually, however, practically all copper and copper-alloy products are recycled. Main sources of recyclable copper are new scrap and old scrap. New scrap is basically surplus metal, with no impurities, which is generated during the manufacture of products and components. It includes turnings from machining operations, trimmed flash from forgings, webbing from stamping or pressing, and miscellaneous offcuts from tube, fittings and other manufacturing. Since these items are directly usable, they can be remelted by mills producing rod, bar, sheet and strip, tube and pipe, as well as foundries and ingot-manufacturers.

Old scrap is recovered from goods and equipment that have reached the end of their service life as a result of obsolescence, wear or damage. Such items range from those containing highly pure copper (old plumbing tube, electrical wire and electric motor windings), to lower copper-content ones (plumbing fittings, valves, radiators, and microprocessor circuit boards). The recycling value of electronic equipment is often enhanced by its precious metal content. High-purity old scrap is used by fabricators and ingot-manufacturers whereas lower copper-content scrap is usually processed by custom smelters that can handle such complex materials.

Copper-processors and manufacturers also generate intermediate process scrap which contains copper. Examples of process scrap are slags, drosses, skimmings, ashes and filter dust. Again, due to the variable complexity and composition of such scrap, it is normally processed by custom smelters. The scrap trade is generally a multi-tiered business with various relationships between levels. At the first level, one finds the local metal-dealer who collects and sorts old and new scrap from individuals, demolition sites, industrial accounts and other sources. Depending on the quality and quantity of the scrap, the collector will deliver it to brass mills, foundries, ingot-manufacturers, or, in the case of lower-quality scrap, to smelters.

New scrap generated by forging companies and manufacturers of screw machine products often bypasses the scrap-collector on its way to the next level. At the intermediate level, the ingot-manufacturer plays an important role by processing old and new scrap from scrap-dealers and industrial accounts into high-quality ingots of known and consistent composition.

In summary, new or old copper scrap may travel one of a number of paths in the recycling system. The flexibility to utilize varying grades of copper scrap at many different processing stages enables the copper-recycling system to conserve both resources and energy.

It is little wonder that copper-recycling is often referred to as the biggest and most economical copper mine.

— From “Canadian Copper,” a quarterly publication of the Canadian Copper & Brass Development Association in Don Mills, Ont.