A NEW MICROPARTICLE TO IMPROVE DRAINAGE OF A NSSC-CONTAINING FURNISH

摘要

This study investigates the use of a new microparticle, a synthetic metal silicate (SMS), for drainagernenhancement of a 40% NSSC-containing furnish. The use of cPAM flocculants traditionally improves the finesrnretention yet causes additional water entrapment in the formed sheet. Because of this, increasing cPAM dosage isrnunable to improve the gravity drainage of the stock, and vacuum dewatering of this same stock, as measured inrnthe laboratory, worsens. The use of a retention and drainage program composed of a flocculant and SMS yieldsrnsimilar or higher fines retention while improving both the gravity and vacuum drainage of the furnish.rnLaboratory observations were confirmed with a NSSC-containing corrugated medium machine trial, where arncPAM/SMS program maintained retention and improved drainage compared to the cPAM single componentrnprogram leading to increased machine speed, establishing two new world speed records on heavy basis weightrngrades. A 12% increase over the average reel speed for a lighter basis weight grade was also attained. Thesernresults will be presented and discussed.