How to make pulp

Usually, the process is crushing, cooking, washing, screening, bleaching, purifying and drying plant fiber raw materials.

A new biological pulping method has been developed in modern times. Firstly, special strains (white rot fungi, brown rot fungi and soft rot fungi) are used to decompose lignin structure, then the remaining cellulose is dissociated by mechanical or chemical methods, and then bleaching is carried out.

In this process, most lignin has been opened by biological decomposition, and chemical methods only play an auxiliary role. Compared with the traditional method, it uses less chemical products, so it can discharge less or no waste liquid, which is an environmentally friendly and clean pulping method.

Extended data

Pulp manufacturing adopts chemical or mechanical methods, and the combination of the two methods to dissociate the fibers in these fiber raw materials, and then purify or refine them into colored pulp or bleached pulp. Chemical pulping methods include alkali method, sulfite method and solvent method. Alkaline pulping is divided into lime method, caustic soda method, sulfate method and sodium polysulfide method.

Pulps can be classified according to the types of raw materials, pulping technology and pulp yield. Sulfate pulp is made of fiber raw materials (all kinds of wood, grass, poor quality waste, etc.). ) and liquid medicine with sodium hydroxide and sodium sulfide as main components at a certain temperature and pressure. It is named kraft pulp because of its brown color and high strength of paper.

Sulfate pulp is widely used. Natural pulp is mainly used to produce industrial and technical paper, such as wrapping paper, bag paper, cardboard and electricity. Its bleached pulp is mostly used to make high-grade cultural paper, and refined pulp can be used as dissolved pulp.

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