Mass Balance

Definition

An accounting method that applies conservation of mass to a defined system boundary, where what accumulates inside equals what flows in minus what flows out.

Applying the mass balance means checking feed rates, load, cycles of concentration, makeup chemistry, blowdown, air ingress, and condensate return. A reading drifts out of bounds because the inputs, outputs, or concentrating fractions changed, not because the chemical alone changed. It is the fourth step of the Blueprint Method and the quantitative core of system reasoning. It connects a measured symptom to a physical change in the flows.

Related concepts

Chemical Demand · The Four Questions · Makeup Water

How it connects

• this measures Cycles of Concentration

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Part of The Blueprint of Water · 🛠️ operations