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Problematic fractions in WEEE
Our environment can also be exposed to hazardous substances during WEEE management. This can cause problems but by addressing them, we can keep the environment safe.
Hazardous substances
in WEEE
Examples of hazardous substances
- Heavy metals: Lead, mercury, cadmium, chromium, tin and antimony.
- Persistent Organic Pollutants (POPs).
- Chemical substances that persist and accumulate in the environment, causing harm to the environment and human health.
- E.g. Brominated fire retardants (contained in plastic parts of e-waste).
- Unintentional Persistent Organic Pollutant (UPOPs).
- Chemical polluting substances, which are released to the air through. uncontrolled open burning of cables e.g:
Batteries (LIB, lead-acid, others)
- Different battery types lead to different challenges
- Lead-acid batteries should be sent to competent recycling facilities
- Lithium-ion batteries are very common in modern electronics. When damaged they can short circuit and catch fire.
- Special care should be taken regarding storage of LIB as well as during dismantling of pouch cell batteries (often glued in and difficult to remove)
- Mixed household batteries (Ni-Cd, alkali and button cell batteries) often contain heavy metals (Cd, Hg) and have to be handled accordingly.
Valuable resources:
- Copper
- Cobalt
- Nickel
- Lead
- others.
Hazardous/Toxic substance:
- Heavy metals (Hg, Cd, Pb)
- Battery acid
- Flammable electrolyte
Lead-acid batteries
- From large appliances, torches, UPS etc.
LIB
- From Laptop, Tablet, Cellphone etc.
Mixed household batteries
- From toys, tools, etc.
Capacitors
- Capacitors (or condensers) have many usage such as energy storage, rectification of power supply, electrical signals, motor starting energy, etc.
- They are present in any electrical and electronic appliances.
- Their appearance is very diverse.
- Old capacitors are very likely to contain Polychlorinated biphenyls (PCBs) which are very hazardous substances.
Hazardous/Toxic substance:
- PCBs
- various substances of concern
Capacitors in power supplies
Capacitors in ballasts from florescent tube lighting
Microwave capacitors
Capacitors on PWB
Gas discharge lamps
- Gas discharge lamps come in different types and shapes (see below)
- Gas discharge lamps often contain some mercury both in gaseous and solid state. They should not be broken and their storage and treatment requires special attention.
Hazardous/Toxic substance:
- Mercury (Hg)
- Cadmium (Cd)
High pressure discharge lamps
Fluorescent lamps
Compact fluorescent lamps
Hg-containing backlights
- Liquid Crystal Displays generally contain multiple small backlights
- Hg-containing backlights can also be found in older scanners and printers
- These backlights contain mercury and break easily – they need to be removed carefully by hand
- Backlights contain mercury in both gaseous and solid state. Tubes should not be broken and their storage and treatment requires special attention.
Hazardous/Toxic substance:
- Mercury (Hg)
- (Cadmium)
LCD-Display parts
Bottom & top backlight
- From small display
Backlight array
- From large display
Removed backlights
Mercury switches
- Used to open or close an electrical circuit. They contain a drop of liquid metal mercury enclosed in a sealed glass container
- Can be found in washing machines, large ovens, thermostats, fire alarms, doorbells (non exhaustive)
- They are normally found in older devices as their used has been phased out (in most devices) due to the toxicity of mercury
- Mercury switches must not be broken and their storage and treatment requires special attention.
Hazardous/Toxic substance:
- Mercury (Hg)
Mercury switches in different forms as they are found in WEEE
Printer Cartridges
- Ink or toner cartridges are often still present in discarded printers, they should be removed and treated separately
- Toner powder in newer cartridges does not contain toxic chemicals, but can damage the lungs when inhaled and can lead to dust-explosions in mechanical treatment installations
- Liquid ink used to contain toxic heavy metals. Nowadays most inks are non-toxic but care must be taken regardless when dismantling and disposing printer cartridges
Valuable resources:
- Metal scrap
- Plastics
Hazardous/Toxic substance:
- Heavy metals (Hg, Cd, Pb)
- Toner powder
small size cartridges
medium size cartridges
liquid ink cartridges
Large printer and toner cartridge
CRT-tubes
- The Funnel glass of a CRT-tube consists of up to 25% lead-oxide (PbO)
- On the front glass there is a layer of phosphor powder which can contain heavy metals as well as rare-earth metals.
- Attached to the electron gun are two getter pills which contain Barium.
Valuable resources:
- Copper
- ferrous scrap
- (Plastics)
Hazardous/Toxic substance:
- Lead
- Phosphor powder (Hg, Cd)
- Barium
CRT-Cutting machine
Leaded glass
Phosphor powder
Getter pills
Oils (compressor, transformer, radiator)
- Compressors, transformers and some radiators contain oils
- Compressors are a part of any temperature exchange equipment
- Older devices might still contain highly toxic PCB-oils
- The oil needs to be drained over a collection basin and the oil itself stored and treated adequately
Hazardous/Toxic substance:
- Heavy metals (Hg, Cd, Pb)
- Toner powder
Oil-radiators
Transformer
Compressor in heat pumps
Coolants
- Coolants are used in all temperature exchange equipment –> Fridges, Freezers, Air-Conditioners, newer washing machines, tumbling dryers, dishwashers
- Many of the previously used coolants are highly problematic substances for the environment (ozon-depleting and highly potent greenhouse gases)
- Coolants need to be removed from the cooling circuit and stored and treated adequately
Hazardous/Toxic substance:
- HFC (R-23, R-32, R134, etc.
- CFC & HCFC (R-1, R12, R22, R402 etc.)
- Ammonia
removal of coolants from fridges
Insulation foams
- Insulation foams are produced from polyurethane in combination with a blowing agent – previously CFC and HCFCs
- Rigid polyurethane foams have a closed cell structure made from very small bubbles.
- Cyclopentane and other substitutes have been used as blowing agents in later years. Cyclopentane is highly flammable
Hazardous/Toxic substance:
- HFC
- CFC & HCFC
- Cyclopentane
Old fridges
Dismantled freezer
Insulation foam layer in cooling & freezing equipment
Asbestos
- Older electrical distribution panels can contain agglomerate asbestos
- Older devices with heat-resistance requirments (electrical heater, electrical cooking plate etc.) can contain lightly agglomerated asbestos as insulation material
- Devices containing asbestos need do be handled by specialists and stored and disposed of adequately
- Asbestos has later been substituted by ceramic fibers which can also be carcinogenic.
Hazardous/Toxic substance:
- Asbestos-fibers
Electrical distribution panel
Electric heater
Electrical cooking plate
Radioactive components
- Ionizing smoke detectors contain small amounts of radioactive material
- These devices are generally marked with the sign for radioactivity
- Radioactive smoke detectors shall not be dismantled and need to be disposed of adequately
Hazardous/Toxic substance:
- Radioactive material
(e.g. americium-241)
Summary
The table summarizes the fractions found in WEEE and classifies them according to their value and toxicity.
| Fraction summary | Valuable materials | Toxic substances |
|---|---|---|
| Copper scrap | Cu and alloys | |
| Aluminum scrap | Al | |
| Ferrous scrap | Fe and alloys | |
| Glass, wood, cardboard, paper | Glass, wood, cardboard, paper | |
| printed wiring boards | Au, Ag, Pd, Cu | BFR, heavy metals (Pb, Hg, Cd, Cr(VI), Sb), Beryllium |
| Cables | Cu | BFR, phthalates, heavy metals |
| Plastics | Pure plastics | BFR, phthalates, heavy metals |
| Batteries | Cu, Co, Ni, Pb | Heavy metals (Hg, Pb, Cd), battery acid, electrolytes |
| Capacitors | PCBs, substances of concern | |
| gas discharge lamps | Hg, (Cd) | |
| backlights | Hg, (Cd) | |
| Mercury switches | Hg | |
| Printer cartridges | Fe, Plastics | Heavy metals, toner powder |
| CRT tubes | Cu, Fe, Al, Plastics | Leaded glass, Phosphor powder, Barium |
| Oils | PCBs, mineral oils | |
| Coolants | HFC, CFC, HCFC, Ammonia | |
| Insulation foams | HFC, CFC, HCFC, Cyclopentane | |
| Asbestos | Asbestos fibers | |
| Radioactive components | Radioactive material |
Further reading
For additional context, we have included an optional PDF with further reading.