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Practice Math Problems Questions

Math ProblemsQuestion 1 of 60

An activated sludge plant is operating at the following conditions: - Aeration basin volume = 1.50 MG - MLSS in aeration basin = 3,000 mg/L - WAS concentration (WAS TSS) = 8,000 mg/L - WAS flow = 150 gpm - Final effluent flow = 4.0 MGD - Final effluent TSS = 25 mg/L Extra information (not needed for this calculation): RAS flow = 3,200 gpm; SVI = 120 mL/g. Using the MCRT equation below and the conversion 1 MGD = 694.4 gpm, what is the MCRT (days)? MCRT (days) = [MLSS (mg/L) × aeration volume (MG) × 8.34] ÷ [WAS TSS (mg/L) × WAS flow (MGD) × 8.34 + effluent TSS (mg/L) × effluent flow (MGD) × 8.34]