METHOD FOR MULTIPLE-STAGE FINE CLEANING OF FIBROUS MATERIAL IN VORTEX-TYPE CONICAL CLEANERS Russian patent published in 2003 - IPC

FIELD: pulp-and-paper industry. SUBSTANCE: method involves separating quality standardized fibers from wastes at first cleaning stage, with additional extraction of fibers from wastes at subsequent cleaning stages; directing wastes obtained at each stage to subsequent cleaning stage, with wastes of previous stage being removed; directing fibers extracted from wastes to first cleaning stage; additionally grinding fibers and/or wastes extracted during at least one cleaning stage. Method is used for fine cleaning of fibrous materials, such as waste paper and pulp. EFFECT: increased efficiency in cleaning fibrous material by preventing vortex-type cleaners from plugging and improved quality of fibrous material. 3 dwg, 2 tbl, 8 ex