Activated Sludge / Process Calculators

Process calculators covering the core daily decisions in activated-sludge treatment. Metric and US units, with the formula behind every result.

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Process calculators covering the core daily decisions in activated-sludge treatment.

Sludge Retention Time (SRT). Solve for SRT, WAS flow or MLSS.

Daily wasting flow needed to hold a target SRT at steady state, with weekly totals.

Adjust wasting rates to bring MLSS to a target value over a set number of days.

Food-to-Microorganism ratio from BOD/COD load and MLSS/MLVSS.

Sludge Volume Index from settled volume and MLSS.

Return Activated Sludge flow, recycle ratio and resulting MLSS.

Convert between daily flow and weekly totals and calculate solids removed.

Compare two wasting strategies side by side.

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