OUR PROCESS

Printed circuit boards (PCB's) = Printed wiring boards (PWB's) / Fractions containing printed circuit boards

These are typically categorised into different qualities, depending on their gold content. See pictures for examples.

• High grade: gold content of minimum 400 ppm
• Medium grade : gold content of minimum 200 ppm
• Low grade: gold content of minimum 100 ppm
• Very low grade: gold content lower than 100 ppm

For the last category, further distinction can be made depending on the presence of burnables (+ or - 50% of plastic)
HINT: Remove large Al/Fe-parts but be careful - especially in case of shredding and sorting - not to lose valuable (precious) metals in side streams. For high and medium grade boards avoid pre-treatment and ship as they are.

Weighing and sampling of electronic scrap (printed circuit boards and other materials)

Making sure that material is accurately weighed and sampled (thereby providing correct weights, moisture content and representative samples for assaying) is one of the most important steps in an assay-based transaction. Indeed, if the sample is not "representative", how can the supplier get the return he deserves? Furthermore, especially with materials like electronic scrap that contains hazardous substances, precise determination of the material composition is a prerequisite of environmentally sound treatment. At Umicore Precious Metal Refining, the customer has the right to be represented during the weighing and sampling process, thereby increasing the level of trust and confidence. A description of the weighing and sampling procedures used by Umicore is available to our customers on request.

Assaying

Representative samples are assayed by both the refiner's lab and, when desired, by the customer's lab (or alternatively an external lab appointed by the customer). Assays from both labs can then be exchanged and compared, leading to settlement by splitting the difference or, if this is too large, relying on assays by a third party, usually known as an "umpire".
Assaying can be done by a variety of techniques, possibly leading to similar results.
Umicore uses fire-assay (collection on Pb) followed by ICP for final determination and has a century of expertise in low concentrations. A description of the assaying method is available to our customers on request.

Smelting and Refining

The Umicore plant in Hoboken uses a unique metallurgical flow chart, based on copper, lead and nickel as collector metals to secure high recovery yields for all precious metals and numerous other ones. The crucial steps, which turned the Hoboken facility into the most modern and cleanest plant of its kind in the world, have been the considerable investments of close to € 200 million in technology between 1997 and 2003. At the heart of this technological quantum leap is the new smelter (the "Isa Smelter"), which serves as a gateway and upgrading step for most incoming electronic scrap fractions. Any plastics or organic residues contained these are also utilised - as a reducing agent and partly as a fuel substitute. All processes are equipped with highly efficient off-gas and waste water cleaning systems, which make it possible to comply with strict environmental standards, even with difficult and complex feed materials. The plant is certified under ISO 9001 and 14001.
Over 95% of the feed is turned into useful products, and the final slag from the plant is used for construction purposes (e.g. for dyke construction). As to the small remaining, non-usable portion of the feed, toxic elements from the feed such as cadmium (Cd) or mercury (Hg) are also systematically extracted and subsequently disposed of in a safe and controlled way. This clearly avoids the risk of contaminating the environment, which would happen if the materials were not processed in the right way.
Unlike some other operations, Umicore Precious Metal Refining processes electronic scrap on-site up to at least 99.95% fine metals.

Settlement

Each recycling lot shipped to Umicore is settled with the customer on the basis agreements and contracts (link to "toll refining") concluded beforehand. These contracts consider the economical values obtained from recovering the (precious) metals on the one hand and the efforts needed to do this (including off-gas and waste water treatment) on the other. The customer receives detailed documentation, which states the weights and quality of materials received and vouches for appropriate treatment, underlining our commitment to maximising traceability and transparency.