WAS Wasting Rate Calculator – Waste Activated Sludge

WAS Wasting Rate Calculator

Daily waste activated sludge rate — by MCRT target or by MLSS inventory reduction — with wasting pump rate.









Formulas
Method A (MCRT target): Qw (MGD) = [ (V × MLSS ÷ SRT_target) − Qe × Xe ] ÷ Xw
Method B (inventory): WAS (lb/day) = (MLSS_now − MLSS_target) × V (MG) × 8.34;
Qw (MGD) = WAS (lb/day) ÷ (Xw × 8.34)
Pump rate (gpm) = Qw (gpd) ÷ wasting minutes per day
For educational and operational-guidance purposes. Adjust gradually and monitor process response.

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