Drift

Definition

The small quantity of liquid tower water that escapes as fine droplets carried out by the exhaust air.

Modern drift eliminators reduce drift to roughly 0.001 to 0.006 percent of the recirculation rate, making it a minor but nonzero term. Unlike evaporation, drift carries the full concentration of the tower water, so it behaves like uncontrolled blowdown. Together with leaks, unmetered losses change the true mass balance.

Related concepts

Drift eliminator · Cooling tower mass balance · Unmetered losses

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Part of The Blueprint of Water · 🛠️ operations