Study of Refining Behaviors of Hardwood Bleached Kraft Pulp Using Domestic Casting Plates with Different Pattern Designs

Abstract

Short- and thin-fiber pulp such as hardwood kraft pulp was refined by two different plate patterns including coarse filling and fine fillings. The plates was designed by the co-workers and casted by a company in Korea. The plate with coarse fillings had cutting edge length of 354.5 m/rev, and the one with fine filling has cutting edge length of 1,466.8 m/rev. Faster drop of freeness was achieved by the fine filling, which could save refining energy to get a quality specification. The fine fillings created flexible fibers with fibrillation of fiber walls by bruising action which produced high strength and low bulk in paper. Lower bulk and less hydraulic capacity by the fine fillings must be overcome by a novel pattern design for more gentle refining. Finally, it was suggested that a finer pattern design can be developed with combination of improved fiber flow by a fabrication technology of narrow bars.