With the development of economy and the continuous improvement of human living, the demand for paper and paperboard is increasing, while the main wood fiber material of the pulp and paper industry is decreasing year by year. How to solve the problem of supply of wood in the paper industry? How to improve the utilization rate of wood? These are all important research topics of forestry and paper industry in the world today. At present, the wood is regarded as the main raw material of papermaking in the world, and the proportion of wood fiber raw materials accounts for 94%.
In China, due to insufficient resources of wood fibers, paper and pulp industry is mostly supported by straw fibers. The unreasonable raw material structure has led to the backwardness of China’s paper and pulp industry. Therefore, increasing the proportion of wood materials, encourage wood pulp making, establish the wood raw material base and large-scale wood pulp mills, which are the most fundamental ways to solve the backwardness of the paper industry and serious environmental pollution in China. The cultivation and planting of hardwood forests such as poplar and the development of hardwood as raw materials Pulp and paper technology is a quick solution to the shortage of raw materials for papermaking in China and the satisfaction of paper The most effective method for growing demand. This research and discussion are about the feasibility of replacing straw fibers with hardwood as a papermaking material.
About straw pulp making of China
In China, wood resources are insufficient. For a long time, most of materials for paper making are straw. The straw fiber is soft and easy to process, as for the papermaking equipment, they are simple and low-cost. Therefore, in the situation of tight paper supply and increasing demand in China, the development of straw pulp making is Very quick. The statistics show that most are grass-based paper and pulp mills. The output of paper and paperboard accounts for more than 65% of the country’s total output, ranked third in the world. However, scattered growth, difficult collection, inconvenient transportation, and storage limit the scale of pulp mill production. The scale of paper mills is too small, it is difficult to use large-scale equipment, and production technology is backward. The economic benefits are poor.
In addition, the straw fiber is short, contains the high number of miscellaneous cells. The straw pulp strength is low, the generous use of straw fiber limit the quality and variety of paper and paperboard in China. For the development of offset printing paper, strong packaging paper, high-grade cigarette paper, information paper, etc. China has to import a large amount of wood pulp and paper products from abroad every year.
What’s more, the wastewater from small straw pulp mill plants is almost untreated and directly discharged into the rivers and lakes, causing great harm to the ecological environment.
About wood pulp making
Wood fiber has many advantages, such as good quality, large accumulation, concentrated growth, convenient collection, transportation, and storage, which provides favorable conditions for large-scale, high-speed and automation of paper industry. Therefore, the material of the world’s papermaking gradually transits from straw to wood. At the beginning of this century, it has been transformed into a wood-based material structure. At present, the proportion of wood fiber in papermaking materials is 94% (including waste paper), which is rough: wood 64. 4%, waste paper 30. 2%, Grass, and other raw materials are only 5.4%. China’s paper industry should get rid of backwardness, improve product quality and level, improve economic efficiency and reduce pollution. The fundamental way is to develop forestry production and provide excellent fiber materials for the paper industry. Continuously expand the proportion of wood in paper-making materials.
Solution to shortness of wood fibers
Due to long-term development and utilization, the world’s softwood resources are gradually reduced, which can not meet the growing needs of paper and paperboard production. As the production level of the paper industry increases, the proportion of hardwood in pulping materials continues to increase. Japan’s hardwood accounted for 39% in 1962 and has increased to 57%. In the United States, the consumption of hardwood in the pulp industry was less than 15% in 1950 and increased to 31% in 1986. Countries with abundant resources are vigorously developing hardwood pulp and paper. For example, in Indonesia, 500,000 hm2 of hardwood pulp forest has been planted in 5 years, and 2 million hm2 will be planted in 10-15 years, which means provides 60 million m3 of wood fiber raw material, and produce 8 million tons of sulfate pulp.
In recent decades, China has planted a large number of poplar and eucalyptus fast-growing and high-yield forests. According to statistics, the accumulation of hardwoods is 397,500.78 million m3. If we use our superior climate and geographical conditions, we plant a lot of fast-growing High-yield forest, building several hundred thousand tons of large-scale hardwood kraft pulp mill, and building several large-scale hardwood BCTMP and APM P pulp mills, replacing small pulp mills below 10,000 tons, the situation of China’s pulp shortage Will be eased, the quality of paper products, production technology, economic benefits, especially environmental issues will be greatly improved.
