Conductivity as concentration surrogate

Definition

The use of electrical conductivity as a practical real-time proxy for total dissolved solids and therefore for cycles of concentration.

Because most dissolved solids carry charge and contribute to conductivity, COC is usually estimated as tower conductivity divided by makeup conductivity. A conductivity controller holds cycles by opening the blowdown valve above a setpoint. Its limitation is that it does not account for minerals that change form, such as calcium carbonate that precipitates as scale and vanishes from the conductivity reading.

Related concepts

Tracer ion comparison · Cycles of Concentration · Conductivity controller limitation

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Part of The Blueprint of Water · 📏 measurement