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Little problematic fractions

In this section of the module, we’ll be exploring the different types of little problematic fractions, as well as the valuable materials that can be obtained from them.

Printed wiring boards (PWBs)

  • Most valuable fraction of WEEE.
  • Mostly from IT equipment, but smaller circuit boards can be found in almost any WEEE type.
  • Complex composition including base-, precious and rare earth metals but also toxic substances.
  • Improper sorting & treatment of PWBs leads to significant loss of precious metals.

Valuable resources:

  • Precious metals (Au, Ag, Pd)
  • Copper

Hazardous/Toxic substance:

  • BFRs
  • Heavy metals (Pb, Hg, Cr(VI), Sb)
  • Beryllium
Very High Grade
  • Processors, graphic cards
High Grade
  • IT/telecom boards (PC, laptop, server, mobile phones)
Medium Grade
  • IT boards (printers), mixed connectors, LCD monitor boards
Low Grade
  • Boards from CRT (TV & PC), HiFi, power supplies, small domestic appliances, etc.

Cables

  • Cables are found in most WEEE.
  • 30-40% of a cable consist of a metal conductor (mostly copper, some aluminum) which is surrounded by a plastic insulation (generally PVC or PE).
  • Cable plastics often contain plasticizers, flame retardants and heavy metals. They should be handled accordingly.
  • Different types and shapes require different treatment techniques (stripping / granulation) in order to optimally recover the metal fraction.

Valuable resources:

  • Copper

Hazardous/Toxic substance:

  • Plasticizer (phthalates)
  • Flame retardants
  • Heavy metals
Thick black cable
  • stripping
External wires (medium thickness)
  • Stripping / granulation

Flat and internal wires (thin)
  • granulation

Plastics

  • A big variety of plastics can be found in WEEE. They are mostly engineering plastics which have a higher value than household plastics.
  • Plastic casings are bulky – size reduction is essential for transport and storage
  • Mixed and dirty plastics have little value – sorting and cleaning is essential
  • 80% of WEEE plastics are either ABS, HIPS, PC (PC/ABS) or PP
  • BFRs are the most relevant toxic substances in WEEE plastics and BFR contain plastics need to be managed accordingly.

Valuable resources:

  • Clean & pure plastic

Hazardous/Toxic substance:

  • Flame retardants
  • Plasticizer (phthalates)
  • Heavy metals
(bulky) Plastic casings
  • From TVs and monitors
Shredded plastic flakes
  • From TVs and monitors
  • Single plastic type (HIPS)
Recycled plastic granulate