In more and more cases WEEE is separately collected for recycling and reuse. If WEEE ends up in the waste bin as residual waste, the WEEE is landfilled or incinerated.
In case of landfilling, the metals in the WEEE, such as copper, tin or lead, start to dissolve due to the acidification in the landfill. If the landfill is not well controlled, the metals can pollute the environment via the leachate water leaving the landfill. In controlled landfills the leachate water is treated in a waste water treatment installation, giving a contaminated sludge to remove as waste.
In case of incineration, the metals of WEEE end up in the ashes. Some metals are recovered from the ashes. The ash form an incinerator is landfilled in some countries, and used for civil works (e.g. road works) in other countries, still giving concern to the environment.
More metals are recovered by recycling of WEEE. In some cases also plastics of the WEEE are also recycled. The ecological potential is higher, however it is difficult to give numbers, due to the type of WEEE recycled, the amount of metals used in each type of WEEE (differs per manufacturer and in time), and the recycling plant. However examples are:
- Refrigerator: 560.72 kg/CO2-equivalent
- LCD TV: 35.14 kg/CO2-equivalent
- Mobile phone: 0.97 kg/CO2-equivalent
where 1 kg CO2 equivalent is emitted by a standard gasoline car driving bout 6 kilometers.
(source: Baxter et al., High-quality collection and disposal of WEEE: environmental impacts and resultant issues, Waste Management 57 (2016) 17–26)