Pulp making process for paper making

Pulp making is the first step in papermaking, aimed at processing raw materials such as wood, grass, and waste paper into pulp. The commonly used pulp making methods currently include wood pulp method, straw pulp method, and waste paper pulp method. The corresponding pulp making equipment includes steamers, wood mills, thermal grinders, pulp washing machines, bleaching machines, pulping machines, and waste liquid recovery equipment.

     1. Wood pulp method: mainly uses coniferous trees, broad-leaved trees, bamboo and other raw materials for pulp making. The pulping process mainly includes steps such as impregnation, cutting, steaming, and bleaching. Among them, steaming is one of the key steps in pulping, which can transform cellulose and hemicellulose in wood into straight chain structures, facilitating subsequent processing.

     2. Straw pulp method: mainly uses straw, wheat straw, reed and other raw materials for pulping. The production process of straw pulp does not require steaming, only the steps of chopping, soaking, pulping, and sedimentation are needed to complete the pulping process. Straw pulp equipment is relatively simple, but the fiber length and strength of straw pulp are low, and it is generally used as the bottom layer of paper.

    3. Waste paper pulp method: mainly uses various types of paper, cardboard, stationery and other waste paper as raw materials for pulp making. The production process of waste paper pulp includes stages such as classification, cutting, pulping, and screening. The advantage of waste paper pulp is that it can recycle waste paper resources, but it should be noted that adding too many impurities such as ink and dyes to waste paper pulp can affect the quality of the paper.