Makeup Rate from Cycles

Solves for makeup by substituting the blowdown equation into M = E + B. Gives total water that must be added for a given evaporation and cycles.

$$M=E\times \frac{\text{COC}}{\text{COC}-1}$$

Variables

Symbol	Meaning	Unit
M	Makeup rate	gpm
E	Evaporation rate	gpm
COC	Cycles of concentration	dimensionless

Worked example

At 4 cycles with E = 10.2 gpm: M = 10.2 x (4 / 3) = 13.6 gpm. Check: M = E + B = 10.2 + 3.4 = 13.6 gpm.

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Part of The Blueprint of Water