Pulping is the process of separating plant fibers from raw materials of and obtaining pulps. The pulping process can be mainly divided into mechanical method, chemical method and chemical-mechanical method to obtain mechanical pulp, chemical pulp and chemical-mechanical pulp respectively.
Pulping purpose
The lignin is eluted in raw material, and the material is separated into single fibers, and the specific surface area (surface area per unit weight of the fiber) of the fiber is increased.
Pulping requirements
Under the premise that the fiber is not damaged or less, the plant fiber is separated into monomer fibers, and the pulp has a certain specific surface area and interlacing performance, which creates conditions for recombination between the fibers.
Pulping process development
The pulping and paper-making industry is an important industry in the development of national economy. It has experienced several development stages and still holds an important position in national economy. Throughout the development of the pulping process, we have seen that there are many ways to make pulp. But the alkaline pulping method is influential. Conventional alkaline pulping method includes lime process, caustic soda process, sulfate process, sulfite process, and pre-hydrolysis process. Among them, caustic soda method and sulfate method are mainly used, and two methods can be widely used for cooking various raw materials, and can also be used for producing semi-chemical pulp and chemical-mechanical pulp. In recent years, in order to accelerate the release of lignin, to protect cellulose and hemi-cellulose from degradation, thereby increasing the yield of pulp, improving the quality of pulp, or in order to reduce environmental pollution, the alkaline pulping develops very fast with various additives. At present, the production of wood pulp is mainly based on the sulfate method in China and abroad. The production of straw pulp is still based on the alkaline method (including the sulfate method), while the caustic soda method and the alkaline sulfate method improves very quickly. Its pulping yield is high, the whiteness is good, and pulp strength is high. It is easy to wash, bleach and has less foam, etc. It has obvious advantages, and the development prospects are optimistic.