Clotting washing

摘要

PCT No. PCT/CA91/00350 Sec. 371 Date Jun. 25, 1993 Sec. 102(e) Date Jun. 25, 1993 PCT Filed Sep. 27, 1991 PCT Pub. No. WO92/06241 PCT Pub. Date Apr. 16, 1992.Brown stock washing of wood pulp is improved by adding a water-soluble cationic polymer to the wash water. The cationic polymer reacts with lignin solution present in the larger channels in the pulp mat to give a precipitate which lowers the flow rate of wash water through the larger channels. A more efficient wash water usage is obtained.