10 07 29 Master thesis Juliana Leon - e-Waste. This guide

Non treated (low-grade
PWBs)
Formal treatment &
export
Worst case
Best case
Base scenario
Refurbish
Informal extraction
Total generated
0 200 400 600 800 1,000 1,200
Scrap computer PWBs [tons/year]
Figure 23: Generated quantities and final destination of scrap computer PWBs in Colombia for
the year 2009 according to the three scenarios.
The hypothesis that all PWBs from monitors passing through the “informal
dismantling” process are landfilled or dumped results in huge quantities of potentially
hazardous components that are not treated.
3.4.6 Assessment of plastic flows
The main issue with plastics originating from computer waste is their potential
content of brominated flame retardants (BFRs) such as polybrominated dipheniethers
(PBDEs). Especially two commercial products from the PBDEs family can be found in
computers: OctaBDE most used in ABS (acrylonitrile butadiene styrene) and
DecaBDE in HIPS (high-impact polystyrene) (Sepulveda et al., 2010). No flawless
solution exists: on the one hand, to landfill plastic casings represents a loss of
resources, and on the other hand, plastic recycling can be questionable due to the
potential release of hazardous substances such as polybrominated dibenzodioxins,
during the recycling process (Wäger et al., 2009). However, in the case of Colombia,
the MAVDT, EMPA, and the CNPMLTA are privileging plastic recycling over state-ofthe-art
incineration and do not consider the final disposal as an option (Ott et al.,
2010).
Concerning the fate of plastics in the system, the field survey revealed the existence
of a recycling market in the formal sector but neither in the IS nor an interface
between both sectors as demonstrated by Figure 24. Formal companies, have the
capacity to carefully sort all kind of plastics, to clean them (e.g. by removing stickers)
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