FRACTIONATION APPARATUS AND METHOD IN FRACTIONATION OF STOCK IN A PAPER MACHINE OR EQUIVALENT

摘要

The invention relates to a fractionation apparatus and a method in fractionation of stock in the short circulation of a paper machine or equivalent. The fractionation apparatus comprises a fractionation screen (21) in connection with a centrifugal cleaner (15a1) of a centrifugal cleaning stage (Pol) of a centrifugal cleaning plant (15). By means of the fractionation apparatus one first layer of a web is formed out of stock which is formed of stock passed as accept from the centrifugal cleaner (15a1) of the first centrifugal cleaning stage (Pol) of the centrifugal cleaning plant (15) and, in addition, of stock passed as accept from the fractionation screen (21). At least one second layer of the multi-layer web is formed out of a second fraction which is formed of stock passed from a centrifugal cleaner (15a2) of some lower centrifugal cleaning stage of the centrifugal cleaning plant (15), which stock comprises, in addition, a stock portion passed as reject from the above-mentioned fractionation screen (21) through a reject line (23 and/or 24).