Discussion on the purification of make-up circulating water for cooling towers
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This post was last edited by wwyyxxz on 2015-8-6 09:35. As the title suggests, I’m interested in knowing how people purify the circulating water in their cooling towers – is demineralized water or softened water used? Should I just add the chemical directly?
Our company uses the concentrated water from RO membranes and some tap water for replenishing the circulating water.
Tap water is used for making up water, and a side filtration unit is suitable for purifying circulating water.
Also, when sodium chloride is used to soften water, won’t the chloride ions corrode the equipment?
Requirements for the quality of water used for replenishing circulating water: Sequence Number, Control Parameter; For open-loop circulating cooling water systems, 1 pH value: 6.5–8.5, 2 Turbidity (NTU): ≤ 5, 3 Colority (degrees): ≤ 30, 4 Biochemical Oxygen Demand (BOD5) (mg/L): ≤ 10, 5 Chemical Oxygen Demand (COD Cr) (mg/L): ≤ 60, 6 Total hardness (as CaCO3/mg/L): ≤ 450, 7 Total alkalinity (as CaCO3 mg/L): ≤ 350, 8 Sulfates (mg/L): ≤ 250
RO membrane, pure water? The investment cost is too high