Patent ID: 6551462
Filing Date: 2003-04-22
Classification: D21C

Abstract:
A system for producing chemical cellulose pulp from comminuted fibrous cellulose material, comprising:a steaming vessel in which comminuted fibrous cellulose material is steamed to remove air therefrom; a superatmospheric pressure vertical treatment vessel having an inlet for a slurry of comminuted cellulose fibrous material at a top portion thereof and an outlet at a bottom portion thereof; pressurizing transfer means for pressurizing a slurry of material from the steaming vessel and transferring said slurry of material to said treatment vessel inlet, said pressurizing transfer means consisting of one or more high pressure slurry pumps, each having an inlet and an outlet, located below said top portion of said treatment vessel; and means for circulating liquid from said top portion of said treatment vessel to an inlet or outlet of said one or more high pressure slurry pumps.