Upon collection at the source, hazardous wastes are transported
to the appropriate processing facility according to their type (blue
lines in Fig. 2). The model allows colocation or establishment of
integrated facilities at the same node. It is especially important that
incinerators and landfills be integrated since residues from hazardous waste incineration are likely to be hazardous and must be
sent to a hazardous waste landfill.
The proportions of treatment and incineration residues with
respect to total amount of waste entering a process step are ob-
tained from the literature and current practices. They are incorporated into the model by means of mass reduction ratios (denoted
by upper case M in Fig. 1) provided in SI Table S1. These coefficients
represent the relation between the amount of waste and the
amount of residues entering the process and are needed for flow
balance constraints.