Modern High-speed Newsprint Machine Production Of Light Weight Light Paper

Bulk paper becomes more and more popular for its advances such as good color, high bulk, good stiffness and cost. It is not only used for the printing of novels book widely, and also the school textbooks and textbooks provided in order to reduce the weight of schoolbags and protect the eyesight of students. So the bulk paper becomes one of the paper with good market prospects.9#paper machine in Huatai Group is mainly a newsprint paper machine, which annual output is160thousand tons and papermaking width is6350mm, and designed machine speed is1,200m/minute. Due to the current bad market condition, the bulk paper was produced in9#paper machine, because the properties and structure of the paper machine such as double wire formation, double lined drier and soft cylinder are suitable for cultural paper.The technical conditions such as furnish ratio and chemicals added for high quality bulk paper production was studied, and the bulk paper with good quality was produced in paper machine with high speed.The furnishes ratio was determined based on the different properties of aspen BCTMP, bleached soft and hardwood pulp(BKP) and deinked pulp(DIP), and the their influence on the bulk, thickness, physical properties, brightness and opacity was studied. The beating characteristics of BCTMP and it effect on the properties of paper was mainly studied due to the high ratio of BCTMP in furnishes. The optimum pulps ratio is BCTMP:BKP:DIP=60:20:20In order to improve the surface properties and opacity and reduce the cost,5%PCC was used as filler in papermaking. The optical brighten agent(OBA) dosage was0.05%. AKD was used as sizing agent, which dosage was0.4%and pH was7-7.5. The retention system and the dosage of retention agents was determined, and CS-CPAM system was chosen as the retention system in wet end, in which CS dosage was1.0%and CPAMP dosage was0.02%and bentonite dosage is0.3%.The production trial was carried out in9#papermachine based on the optimum conditions obtained in laboratory, and the good quality product matching QB/T2809-2006standard was produced. The higher bulk was required by the customers, so the raw materials for DIP and the ratio of three pulps was adjusted, and the pressure oin press section and cylinder section was also optimized, and the bulk of final product reached1.89cm3/g.After switched to bulk paper production successfully, the production benefit was improved obviously, and the aim of the study was achieved and good effect was obtained.