Proceedings - Teaching and Learning Centre - Simon Fraser ...

Fraser River Action Plan 3rd Research Workshop
Contaminants in Wastewater Biosolids (Suspended Solids)
G. Derksen
Environment Canada
A limited number of wastewater biosolids have been collected from various industrial (pulp mills) and
municipal discharges (sewage treatment plants, combined sewer overflows) in order to characterize suspended
solids-associated contaminants (Table 1). The solids were separated from the main effluent discharge using a
continuous-flow centrifuge operating at 4 L/min.
In cases where whole effluent samples were also collected on the same day that centrifuge samples were
collected (e.g., PAHs), the solids had a greater number of compounds (Table 2).
Conclusions
The results for dioxins/furans are shown in Figures 1 and 2, PAHs in Figures 3 and 4, coplanar PCBs in Figure
5 and chlorinated pesticides in Figure 6. For one municipal sample, the centrifuge was passed through a XAD-
2 resin column; both the centrifuged solids and eluted column were analyzed for PAHs. The results clearly
demonstrated the association of higher 1ogKow compounds with the solids (Figure 7).
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