Enhancing the main strength parameters of softwood Pinus fibre by using a new triple cone refiner

摘要

The primary use of softwood fibre is as a reinforcement pulp and, as increasing demands are being put on the performance of all grades of paper the need to optimize the strength of these pulps also increase. For all softwood fibres the main strength parameters, tensile and tear has a great difficulty to be maximized because of the fact that, although tensile increases with refining, tear decreases after a certain amount of energy input. The development of strength is higher at a lower intensity for softwoods but this intensity should not be too low as the softwood fibre is strong and requires fair degree of force to break down the fibre to give bonding sites. The new Triple-Cone refiner due to it's singular refining treatment is able to achieve high tensile parameters before the breaking point where tear properties starts to decrease. It's unique project increase significantly the edge length compared to similar refiners providing such a low intensity refining combined with a longer residence time promoting a more homogenous treatment of the fibres resulting in improved paper characteristics. To prove this theory a comparison trial was made at a U.S. linerboard mill producing 600 t/d using Pinus taeda Softwood fibre which is typical South American softwood. This mill has 8 (eight) double disc refiners 38" and installed one Triconic RTC-4000 in the place of one of them to run in parallel with the others. This report will show the comparisons of parameters such as tear, tensile, CMT and RCT (important for this type of paper) achieved by the Triple cone refiner and the double disc refiner on similar flows and power applied and the concepts of both technologies.