PERIODIC METHOD FOR CELLULOSE COOKING AND CELLULOSE PRODUCTION PROCESS Russian patent published in 1999 - IPC

FIELD: pulp-and-paper industry. SUBSTANCE: invention is designed to improve whiteness of cellulose and consists in combining feeding white lye between operations of warm filling, hot filling, and cooking involved in periodic low-temperature cooking process. Total content of white lye is high and constitutes 15 to 35% of active alkalinity. Cooking temperature lies between 150 and 168 C. White lye is added to warm black lye in the stage of preliminary treatment with warm black lye, to hot black lye in the stage of preliminary treatment with hot black lye, and to cooking lye in cooking stage. EFFECT: increased whiteness of cellulose. 11 cl, 12 dwg, 15 tbl