The development and future prospect of pulp and paper technology

Bleaching is also a common process in the paper industry, in the ancient bleaching technology has not yet been born, the quality of paper is poor. We all know that lignins and extracts are the reason for the other colors of the pulp, and the purpose of bleaching is to add chemicals to improve the whiteness of the pulp. There are two common bleaching methods, one is to only let the chromophore group decolorization and retain the lignin, such bleaching is commonly used disulfite and sodium borohydride. The other type does not retain the lignin, and uses bleach to oxidize and dissolve the lignin. The two kinds of bleaching methods are that the former has a higher yield, but the whiteness of the obtained pulp is not high; The latter has a large loss and a low gain rate, but can obtain high whiteness pulp. In the actual production process, bleaching methods can be reasonably selected according to the different paper yield and whiteness.

In addition to the above two categories of traditional bleaching methods, hydrogen peroxide bleaching method has been more and more widely used in recent years. In the traditional bleaching methods, most of them use the reducibility of chloride ion for bleaching, and hydrogen peroxide, as a chlorine-free bleaching agent, has its unique advantages. The use of hydrogen peroxide as a bleach agent is to use its HOO- functional group, passivating and even eliminating the chromophore group, but can maintain the original structure of lignin. Because of its unique chemical properties, it is sometimes used as a multi-stage bleaching process to change the structure of the hair base group and maintain the whiteness of the pulp. However, its disadvantage is that the improvement performance of hydrogen peroxide for pulp whiteness is very limited, generally about 8%-10%.

4. Application prospect of chemical pulping technology

The role of chemical science and technology in improving pulping technology is self-evident, and with the continuous development of science and technology, new technologies will continue to be applied to pulping technology. Objectively speaking, although China is a large country in the manufacture and consumption of paper products, there is still a certain degree of gap between China's equipment manufacturing industry and Western developed countries, and the pollution problem caused by the paper industry is still severe. Simple use of mechanical pulping, the efficiency is relatively low, the production cost investment is large, and will inevitably cause more serious environmental pollution, so it is foreseeable that chemical pulping technology is bound to be more and more applications. The scientific concept of development requires us to develop environmentally friendly industries, as an industry with large environmental pollution, the paper industry needs to continue to innovate, analyze various problems in the paper making process, and use chemical methods to solve them. In general, chemical pulping technology is bound to get more and more broad development and application prospects in the future.

5. Conclusion

Whether the pulping technology is mature determines the quality of the paper, so it is very important to improve the pulping technology. Compared with traditional mechanical pulping, chemical pulping technology has its unique advantages, but we should also pay attention to absorb the advantages of mechanical pulping technology in the production process, integrate the advantages of chemical pulping technology and mechanical pulping technology, and constantly improve the pulping technology, catch up with the international advanced level, constantly improve the pulping level, and improve the quality of paper making. Solve the problem of environmental pollution caused by the papermaking process and develop environmentally friendly industries. Research on chemical agents in the process of cooking and bleaching should be carried out to improve the yield and further improve the method of pulping whiteness. Practitioners in the paper industry should constantly improve their professional literacy, improve professional quality, constantly understand and learn advanced foreign pulping technology and apply it to production, strive to achieve greater development of China's paper industry at a smaller cost, and constantly improve China's existing pulping technology.