CORROSION OF BRASS IN COOLING WATER SYSTEMS - ROLE OF MANNICH BASE DERIVATIVES

Abstract

: Brass has been widely used as the material of construction of condenser tubes, pumps and impellers of raw cooling water systems of power plants. The corrosion of brass therefore takes oil greater significance, as the systems are susceptible to dezincification. Azole compounds used as inhibitors suffer from the limitation that they are susceptible to degradation by halogen-based oxidizing biocides, which are used to control microbial growth. This results in an additional demand oil the oxidizing biocide and an increase in the chemical consumption of the cooling water system, warranting the development of alternative inhibitors to prevent the corrosion of brass in cooling water systems. The aim of the present investigation is to evaluate the suitability of Mannich base derivatives, namely, 4-methyl-2-formyl-6(piperidine-1-yl methyl) phenol (MFPP) and 4-methyl-2-formyl-6(morpholine-1-yl methyl) phenol (MFMP), as corrosion inhibitors for brass in cooling water systems, under simulated conditions. Both compounds exhibit good inhibition efficiency towards the corrosion of brass under varying experimental conditions. Their ability to perform as a self-indicator aids in continuous monitoring of cooling water systems.