Increased flocculation of kraft pulp fibres with enzyme treatment

摘要

The flocculation behaviour of a linerboard furnish during and after treatment with crude cellulase enzyme was compared with an untreated control pulp. The flocculation tendency was evaluated at papermaking fibre concentrations by optical measurements in a closed-channel flow loop, and at higher fibre concentrations using friction loss measurements in a pipe flow loop. The friction loss behaviour only changed at a high enzyme dose with the pressure loss increasing over the entire velocity range. At the same time the cessation of plug-wall interaction occurred at a higher flow rate and the level of maximum drag reduction was lowered. Floe size analysis in closed-channel flow showed that average floe size increased. Therefore, cellulase treatments could lead to greater fibre flocculation tendencies and increased network strength.