Timothy Keister, chief chemist at ProChemTech International Inc., Brockway, Pa., was awarded U.S. Patent No. 8,496,847, “Method and Composition for Operation of Evaporative Cooling Towers at Increased Cycles of Concentration.”

This patent discloses a method and composition for operation of an evaporative cooling tower using hard, alkaline makeup water at increased cycles of concentration (COC). The method involves using the following equation to calculate the COC obtainable with the composition:

Prochemtech equation for patent

Where CaH is calcium hardness and TA is total alkalinity, both measured as CaCO3 .

According to Keister, a certified water technologist (CWT) and Fellow of the American Institute of Chemists, the cooling tower water is dosed with a chemical composition consisting of phosphonate and organic polymers to obtain a phosphonate level of 7 to 14 mg/l, which prevents scale formation at the calculated COC.

The company asserts that the COC obtainable by this method and composition allows cooling towers to be operated two COC higher than can be obtained by competitive methods. Operation at a higher COC cuts cooling tower blowdown, reducing both fresh water use and sewerage discharge, decreasing overall operating costs and conserving natural resources.

ProChemTech is marketing the water treatment technology under the HighCycle trademark.