5 questions about using X-ray fluorescence to refine copper

1. Why is copper refinement a hot topic in metal recycling?

In the past, mixed metal packages like zorba were exported out of the U.S. Today, there are many benefits to keeping metal units in the domestic market for both producers and consumers; but, to do so, the products must be higher quality.

Producers who have been able to create high-quality copper products have benefitted economically with higher copper pricing, which always generates interest. Additionally, the future demand for high-quality copper fractions appears high as a couple large corporations have announced U.S.-based smelting and refinery locations.

2. Where do the material streams for recycling mainly come from?

Much of the material is generated from shredding of end-of-life-vehicles (ELVs) and white goods/appliances, as well as from incinerator bottom ash (IBA). For copper specifically, there are packages of copper wiring and tubing (Institute of Scrap Recycling Industries, or ISRI, specification packages like birch/cliff, berry/candy) that would be infeed.

3. Which technologies are needed to create pure copper fractions?

X-ray fluorescence (XRF) technology is the right fit for pure copper fractions as it is sorting based on an analysis of elemental composition.

When analyzing by element, copper can be separated from zinc, brass, stainless steel, lead or other heavy metals based on the chemical composition. This elemental analysis still can be achieved when surface residue is present, as is often the case with IBA and/or metals from a wet media system.

4. Why do you offer two different sorting principles for copper refinement?

Depending on the size and shape of your material stream, Steinert provides two XRF sorting solutions: A sorting system with a belt or with a chute. In the STEINERT KSS | XF, the material passes the XRF detection (and other sensors) by means of a conveyor belt. With the STEINERT CHUTEC, the material falls past the sensor and is detected and ejected out of free fall. The STEINERT KSS | XF platform is used for larger materials, while the STEINERT CHUTEC is used for fine material streams or streams with many spherical/rolling pieces.

5. As copper is an end product, which sorting steps are applied prior the refinement?

In most refinement plants, magnetics are first used to remove iron attachments, and an eddy current separator recovers the nonferrous metals.

After that, STEINERT X-ray transmission (XRT) technology separates the heavy from the light metals.

XRF is the last sorting step to create the pure copper from the mixed heavy metal infeed.