ELECTROCHEMICAL STUDIES WITH COUPLED MULTIELECTRODE ARRAY SENSORS ON CORROSION INHIBITION OF COPPER AND AFFECTED METALS IN THE PRESENCE OF AMMONIA AND OTHER CORROSIVE IONS IN ZERO LIQUID DISCHARGE COOLING WATER

摘要

Studies were performed with coupled multielectrode array sensors (CMAS) to establish the corrosion inhibition performance of azoles corrosion inhibitors for copper and metals normally corroded by the presence of ammonia. The studies were conducted with water at high pH and high total dissolved solids (TDS) that result from the operation of an evaporative cooling tower system at zero liquid discharge (ZLD). The study compares the effect of tolytriazole treated versus untreated water with chemistry at pH 10, low hardness (<100 mg/L as CaCO_3) and TDS of 150,000 mg/L along with the presence of silica corrosion inhibitor generated from source water. Laboratory test results are compared with field test results in a comparably treated ZLD system where "reclaim" water which contains significant residuals of ammonia is used for makeup to a cooling system with copper tube exchangers.