Field Test Results of an Anti-Scale/Corrosion Resistant Coating for Hot Water Heat Exchangers

摘要

U.S. Army Directorate of Engineering and Housing engineers and maintenance personnel are frequently faced with recurrent fouling of heat exchanger tube bundles that reduces the thermal efficiency of these systems to the point where they fail to meet hot water demands of various Army facilities. Common maintenance practices that address this problem are costly, labor intensive, and involve hazardous chemical and waste handling. This long-term field study examined the effects of applying a phenolic coating to the heat exchanger bundles in domestic water storage heaters (DWSHs) to prevent scaling and creating a virtually maintenance-free system. It was found that: (1) the phenolic-based composite coating system applied to potable water heat exchangers at Fort Hood maintained the temperature of the hot water at or above 140 deg f for 4.5 years; (2) the coated heat exchangers eliminated the need for 90-day acid cleaning cycles; and (3) the simple payback for a phenolic-based composite coated heat exchanger at Fort Hood was approximately 2 months.