Diminishing returns of cycles

Definition

The pattern in which each additional cycle of concentration saves less blowdown than the one before, so the largest water savings come from the first improvements.

Going from 2 to 3 cycles halves blowdown, 3 to 4 cuts it by a third, and 4 to 5 by a quarter, with savings flattening past about 6 cycles. Water savings flatten but scaling risk does not, since every species keeps multiplying. A tower evaporating 25 GPM saves nearly 4 million gallons per year going from 3 to 6 cycles but only about 1.2 million more going from 6 to 10.

Related concepts

Water efficiency versus chemical risk · Cycles of Concentration · Blowdown

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Part of The Blueprint of Water · 🛠️ operations