Biocide Efficacy

Definition

The biological control power of an oxidizing biocide, which depends on the fraction present as the stronger oxidizing species.

As pH rises, free chlorine shifts from hypochlorous acid toward hypochlorite ion, weakening the oxidizing species available for biological control. Biological pressure then increases without any change in feed rate. A biocide gap or pump failure lets planktonic bacteria bloom into biofilm, after which oxidant demand stays elevated even once the biocide is restored.

Related concepts

pH Drift · Chemical Demand · Microbiological Growth

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Part of The Blueprint of Water · 🧪 chemistry