Treatment Concentration & Mass Removal Calculator

How the treatment concentration & mass removal calculator works

Concentration reduction percent = (inlet − outlet concentration) ÷ inlet concentration × 100. Each mass rate in kg/day is m³/day × mg/L × 0.001. Mass-rate reduction percent = (inlet load − outlet load) ÷ inlet load × 100. A zero input denominator makes its percentage unavailable.

Use the same constituent, representative sample period and flow boundary. A concentration reduction is not automatically equal to a mass reduction when flows differ. Negative removal is retained for data review rather than clipped. This arithmetic does not establish permit compliance, treatment adequacy, an operating target or a chemical dose.

Quantities use the stated units and finite bounded inputs. Whole purchases round up under the documented model; cost components round half-up to cents before totals are summed. Undefined ratios stay unavailable. π and logarithms use normal numeric precision. Display rounding does not alter the entered assumptions.

Worked example

At 200→50 mg/L, concentration reduction is 75%. With 100 m³/day inlet and 80 outlet, loads are 20 and 4 kg/day, so mass reduction is 80%. Raising outlet concentration to 100 mg/L gives 50% concentration reduction and 60% mass reduction.

Sources and assumptions

The source material explains the underlying calculation or pricing structure. Entered prices, costs, schedules and scenario choices are your assumptions; this tool does not obtain supplier quotes or predict actual results.

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