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sci.BOD-first-order-decay Calculator
Calculates biochemical oxygen demand exerted at time t using first-order kinetics: BOD_t = L₀(1 − exp(−k₁t)), where L₀ is ultimate BOD and k₁ is the deoxygenation rate constant. BOD₅ (5-day, 20 °C) is the standard wastewater strength parameter — it represents roughly 60–70% of ultimate BOD for municipal sewage.
Inputs
Bod0 Mg L
Reference formula or conversion factor shown for context.
K1 Per Day
Amount per unit of time or per unit quantity. Check the denominator before interpreting.
T Days
Duration of the process. Make sure units match the rate inputs (seconds, minutes, or hours).
Results
BOD exerted at time t (mg/L)
The computed duration or time value.
BOD remaining (ultimate) (mg/L)
The value at the specified point or condition.
BOD₅ fraction
Sample size or count used in the calculation.
BOD(t) = BODu·(1 − e^−k₁t)
Reference formula or conversion factor shown for context.
k₁ temperature note
Supplementary information explaining an assumption, caveat, or important context for interpreting the result.