CORROSION INHIBITOR FOR CONCENTRATION VESSEL FOR BLACK LIQUOR IN PROCESS FOR PRODUCING KRAFT PULP, AND CORROSION INHIBITION THEREFOR

摘要

PROBLEM TO BE SOLVED: To obtain a corrosion inhibitor effective for inhibiting the corrosion of a black liquor concentration vessel in a process for producing a kraft pulp, and further to provide a method for inhibiting the corrosion of the vessel for concentrating the black liquor by using the corrosion inhibitor. ;SOLUTION: This corrosion inhibitor effective for inhibiting the corrosion of a black liquor concentration vessel in a process for producing a kraft pulp contains a water-soluble copolymer comprises a terpolymer composed of an acrylic acid component, a maleic acid component and a hypophosphorous acid component regulated so that the molar ratio of the acrylic acid component to the hypophosphorous acid component may be (1:3)-(3:1) and the percentage of the hypophosphorous acid component may be 1-20 mol.%, and having 500-10,000 weight average molecular weight as an active ingredient. The method for inhibiting the corrosion of the vessel for concentrating the black liquor comprises adding 1-100 ppm of the corrosion inhibitor to the black liquor.;COPYRIGHT: (C)1999,JPO