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

The flows of PWBs within the formal and the informal sectors as calculated with the
base scenario are presented in Figure 22. Although the majority of medium and highgrade
boards finally end up at the formal e-waste recycling companies, only a small
part arrives there via the formal pathway. This is also shown by the highest flow in
the model that is the one going from “informal collection” to “informal dismantling”.
This flow is composed of PWBs still part of entire devices and also of isolated PWBs
that the recicladores obtain from computer shops.
Figure 22: Material flows of computer PWBs within the formal and informal sector in Colombia.
Base scenario calculated for 2009.
Once again, as the formally treated part is well known, the difference in the total
generated quantity between the scenarios is distributed into “disposal” and “informal
extraction” processes (Figure 23). The fraction of the total generated scrap PWBs
that is currently going to “informal extraction” is almost zero for the “best case
scenario”, 8.2% for the base scenario, and 22.8% for the “worst case” scenario.
Although the quantity of informally processed PWBs is always lower than the one
that is formally treated, up to 295 tons of computer PWBs (worst case) can undergo
artisanal processes, making this practice maybe not as sporadic as initially thought.
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