The Effect of Mechanical Pre-treatment of Reject Pulp as Raw Material for LOCC Mixture on Medium Paper Quality

Abstract

Reject pulp is pulp that is stuck in the screen hole during the pulp screening process because it is larger than the screen hole and has shives (more than two fiber chains that are still bonded), as well as blackish brown knots. Reject pulp from the process will be stored in landfills resulting in accumulation which can pollute the environment if the amount continues to increase in line with the production being carried out. Therefore, innovation is needed so that rejected pulp can be reprocessed. The current problem in the industry is reject pulp which has the effect of decreasing the value of paper properties and causing the surface of the paper to become rough. In this study, pre-treatment will be given for screen and material blending during beating. This study aims to determine the potential of reject pulp to be used as a mixture of LOCC raw materials on medium paper and the most optimum mechanical treatment to produce the best quality medium paper. The results in this study obtained the optimum value for the pre-treatment screen beating itself, namely a bursting factor of 27.70 g.m2/g.cm2, a tensile index value of 39.18 N.m/g, and a smoothness value of 9.425 Sec/10 ml. Meanwhile, the ring crush value obtained was the optimum value for the pre-treatment screen beating mix, which was 11.25 N.m/g. These results have met the standard properties of medium paper.