Stormwater Suspended Solids Removal Coalescing Plate Separator
Abstract
Reducing quantities of stormwater suspended solids removal to receiving bodies improves water quality and is often necessary to meet regulatory requirements. Particulate material, mobilized by stormwater, negatively affects receiving lakes, rivers and streams. A laboratory study of total suspended solids (TSS) removal efficiency was conducted on a coalescing plate separator, designed and provided by Mohr Separations Research (MSR), at varying flow rates and influent TSS concentrations. To simulate a typical runoff TSS particle size distribution (PSD) Sil-Co-Sil 106 (SCS), a commercially available ground silica product with a median particle size of 20 µm, was used. Approximately 30% of solids in SCS are smaller than 10 µm and 96% of particles are less than 100 µm. Flow rates tested were 5, 10 and 15 GPM; influent concentrations of 50, 100 and 200 mg/L were tested at each of the flow rates. Removal efficiencies tended to increase slightly at higher influent concentrations and decreased at higher flow rates. Median removals for combined influent concentrations were 67%, 59% and 50% at flow rates of 5, 10 and 15 GPM, respectively.