How to correctly assemble and select refiners in order to achieve the purpose of high efficiency, high quality and energy saving, Nantong Huayan Refiner Research Center conducts research and comparison through practical cases of several special paper mills. It is considered that based on the design principle of refiner, optimizing the assembly form of refiner in pulping process can improve the beating degree, wet weight, uniformity, broom rate, binding force and paper quality of pulp and reduce the power consumption of pulping.
Keywords: grinding type; Assembly form; Beating efficiency; beating degree
The millstone is the "heart" of disc refiner. After 100 years of inheritance, reference and continuous improvement, there are many kinds of grinding discs. Each specification has several to dozens of different tooth types, including disc-type integral grinding discs and fan-shaped split grinding discs. Generally speaking, the tooth profile of grinding disc can be divided into straight-through, semi-closed and fully closed according to the form of groove; According to the use function, the tooth type of grinding plate can be divided into three types: loose type, broom type and cutting type. However, the above classification forms do not exist in isolation, and often appear in combination according to needs in actual production. Except for radial teeth and bidirectional teeth grinding discs, most tooth profiles have a certain inclination with respect to the radius of the grinding disc. The left inclination is called the left tooth grinding disc and the right inclination is called the right tooth grinding disc (see figure 1). In the pulping production of special paper, different combinations and assembly forms of right and left teeth grinding blades can also obtain different pulping effects, besides selecting the appropriate grinding blade tooth type. (omitted) Han Sixi 1 Wang Xudong 1 Sun 1 2
(Author: 1, Luohe Yin Ge Industrial Group Co., Ltd., Luohe, Henan, 462000; 2. Nantong Huayan Grinding Research Center, Nantong, Jiangsu, 226403)
Combined with the production practice of NCR base paper in Yin Ge Specialty Paper Company, the paper introduces the idea and practice process of exploring with Nantong Huayan Grinding Research Center to analyze the fiber characteristics of imported bleached kraft softwood pulp (NBKP) and bleached kraft hardwood pulp (LBKP), optimize the tooth profile, material and beating process of imported and domestic double-disc mills, improve the pulp binding force and reduce the power consumption of LBKP pulping.
Keywords: beating and grinding; Wet weight; Tooth profile optimization; Split and broom; beating degree
In the pulping process of papermaking production, how to choose the grinding tooth type suitable for a given pulp type and index, to achieve the adaptability and stability of papermaking, and to improve the bonding strength between fiber and paper physical indexes often troubles the pulping section and affects the later production and paper quality. The refiner is the core component that directly exerts multiple effects on fiber raw materials when the refiner works, and the refiner plays a key role in beating quality. In order to meet the market demand, Yin Ge Special Paper Company put into operation a new production line of 50,000 tons imported paper machines in the second phase of 2009 on the basis of the original 20,000 tons of release paper and carbonless copy paper. The raw materials used are imported NBKP softwood pulp and part of LBKP hardwood pulp to meet the NCR base paper production. Two 34-inch Li Qing double disc refiners have high beating efficiency. After put into production, in order to further improve the pulp performance and paper quality, they have strict requirements for Nantong Huayan. This paper mainly introduces the practice of optimizing the tooth profile of LBKP refiner, improving beating index and reducing power consumption, which is only for industry exchange and reference. Zhang Qingyun 1 Jiang Xiaojun 2
(1, Shandong Marriott Paper Group Co., Ltd., Linqu, Shandong, 262600; 2. Grinding Research Center of Nantong Huayan Foundry Co., Ltd., Nantong, Jiangsu, 226403)
Combined with the beating production practice of Marriott Paper's A-class coated paper, this paper introduces the cooperation with Nantong Huayan Grinding Research Center to study and optimize the tooth profile and material of the double-disc refiner, so as to improve the pulp uniformity, improve the smoothness and physical indexes of the paper, reduce the paper breakage of the coater and make the production more stable.
Keywords: optimizing grinding disc; Energy saving; Consistency; Physical indicators; beating degree
1, overview
Marriott Paper uses imported kraft softwood pulp to produce A-grade high-grade coated paper, which not only requires good physical indexes, but also pursues excellent uniformity and printability. Paper evenness not only affects the appearance value of art coated paper, but also affects the physical and optical properties of coated paper [1], which is an important index of coated paper. Paper evenness is the most researched and widely discussed topic in the industry. Nevertheless, in the actual production of many paper mills, it is still the most unstable and difficult quality index to control.
In order to stabilize the physical indexes of coated base paper and reduce the glue holes and paper breakage of coated paper, Marriott Paper Technology Center cooperated with Nantong Huayan Grinding Research Center to optimize the tooth profile and material of the grinding disc of the double-disc refiner from the beating section, improve the pulp uniformity, improve the paper smoothness and physical indexes, reduce the paper breakage of the coater, and make the production more stable. This paper wants to make a brief summary from the perspective of production practice.