Chemical formulation and combined process for inhibiting deposition and corrosion in cooling water and gypsum scaling in flue gas desulfurization scrubber systems

摘要

An inhibitor formulation for inhibiting corrosion and deposition of calcium phosphate, calcium carbonate, and silt in a cooling water system and calcium sulphate (gypsum) scaling in a flue gas desulfurization system. The inhibitor formulation comprises polyacrylate, polymaleic anhydride, and phosphonate in a active weight ratio range between about 1 to 40:1 to 40:0.1 to 15, respectively. The inhibitor formulation is employed to inhibit corrosion and scaling in a combined cooling water/flue gas desulfurization process wherein at least a portion of cooling water blowdown is supplied to make up at least a portion of reagent makeup and/or mist eliminator wash water in the flue gas desulfurization system.