Response of xylanase-treated kraft pulp to Escher-Wyss and PFI refining

The effects of a xylanase enzyme on the properties of an unbleached softwood kraft pulp were investigated after Escher-Wyss and PFI refining. Escher-Wyss refining revealed greater modification of fiber characteristics after enzymatic treatment, with the energy required to achieve a given apparent density reduced by approximately 50%. There was little change in intrinsic fiber strength and the tensile strength-apparent density relationship. The enhanced consolidation of the fiber web was apparently the result of higher fiber flexibility.