Patent ID: 7063770
Filing Date: 2006-06-20
Classification: D21C,D21D,D21F,Y02W,Y10S

Abstract:
1. A method of processing papermaking fibers with a multistage array of forward cleaners including a plurality of centrifugal cleaners configured to generate accepts streams and rejects streams which concentrate hydrophobic contaminants, said method comprising: (a) feeding a first aqueous feed stream including papermaking fibers to a first stage bank of centrifugal cleaners of said multistage array; (b) generating a first accepts aqueous stream and a first rejects aqueous stream in said first stage bank of centrifugal cleaners, said first aqueous rejects stream being enriched in heavy hydrophobic contaminants with respect to said first aqueous feed stream; (c) supplying said first rejects aqueous stream to a flotation stage; (d) treating said first rejects aqueous stream in said flotation stage to selectively remove hydrophobic waste from said first aqueous rejects stream and produce an intermediate aqueous purified feed stream; (e) feeding said aqueous purified intermediate feed stream forward to a second stage bank of centrifugal cleaners of said multistage array, said second centrifugal cleaner being configured to generate a second accepts aqueous stream; and (f) combining said first accepts aqueous stream with said second accepts aqueous stream to form a combined accepts stream.