PULP CLEAN BLEACHING PROCESS

摘要

A pulp clean bleaching process includes: (1) single-stage two-column delignining; (2) hypochlorite bleaching; (3) activator pretreatment; and (4)hydrogen peroxide bleaching. The invention has acheived high efficent bleaching by using unpollutant oxygen and hydrogen peroxide as clean bleach instead of using chlorine gas which produces pollution on environment. In the invention, the bleaching efficiency is high and the whiteness can be up to 85 percent; the construction investment is only one fifth of that of chlorine dioxide bleaching; the level of pollution is lower, AOX is reduced by over 70 percent, waste water discharge is reduced by 70 percent, COD<SUB>Cr</SUB> discharge is reduced by 60 percent. The production line can be newly-constructed pulp bleaching production line or can be formed by reconstruction on the basis of existing pulp bleaching production line, and especially suited for the wood or herbage kind starting material chemical pulp clean bleaching of scale of over 50 tons per day.