Under the condition of the hottest non wood fiber

2022-07-30
  • Detail

The status of non wood fiber (Part 2)

rice and wheat straw raw materials

China uses rice and wheat straw resources for pulping and papermaking, accounting for more than 60% of non wood raw materials. However, it is similar to reed in terms of scale and technical equipment. The scale of most paper mills is also below 60000 t/a, and conventional processes are generally used for pulping and bleaching. In recent 10 years, China has done a lot of work in wheat straw pulping and alkali recovery technology and process, especially in the improvement of equipment. In 1998, under the arrangement of the National Light Industry Bureau at that time, China pulp and Paper Industry Research Institute and Beijing Design Institute of China light industry were organized to systematically test and study the components produced by this kind of method on the technology and process flow of wheat straw pulping and alkali recovery with the help of several enterprises in Shandong, summarize the experience, improve the equipment configuration and process flow, and put forward the recommended technology for the process flow of wheat straw pulping and alkali recovery, The technology of straw pulp production line in China has made a big step forward. The main technologies and equipment are dry and wet material preparation, horizontal tube continuous digester and cold spray, four stage vacuum countercurrent washing system, closed screening system, continuous c-e/p-p three stage bleaching, "two plates and three tubes" combined five body and five effect evaporation system, new single drum low odor furnace and efficient causticization system, etc

4 development forecast of non wood fiber pulping in China

in the long run, the proportion of wood pulp will be larger and larger, and the proportion of grass raw materials will be lower and lower, which is a general trend. However, due to the current shortage of wood resources in China, it is expected that it will be difficult to completely change the existing raw material structure in the short term. Although the utilization ratio of waste paper is increasing rapidly at present, as a primary fiber, pulping and papermaking with non wood raw materials will still occupy a very important position for a long time. In other words, the growth rate of non wood raw materials will be lower than that of wood pulp, but the absolute value of the quantity will not decrease significantly soon

reed raw material

reed mainly grows in the river. When the force is applied to the sample, it will slightly deform the river, lake and other organic matter and water. The development of reed resources depends on the guarantee of water resources. At present, although China vigorously advocates the policies of "returning consumption to forests, farmland to grassland and farmland to lakes", the planting area of reed will increase, but the increase is limited. The main work in the future is to transform the existing reed base to increase the supply of resources, with a density of about 1.3g/cm3. Therefore, reed pulping and papermaking will have a certain development with the gradual increase of reed resources

bagasse raw material

bagasse raw material is a by-product of sugar production from sugarcane, and its quantity depends on the development scale of China's sugar industry. At present, China's sugar industry has basically met the market demand, and it is unlikely to expand the sugarcane planting area on a large scale in the future. In addition, due to the small scale, scattered layout and low utilization rate of bagasse fiber of most sugar mills in China, the amount of bagasse used in pulp and paper industry accounts for only 1/5 of the bagasse output, and most of the bagasse is used as fuel. Therefore, the increase rate of bagasse pulp and paper production in China depends on the full utilization of existing bagasse raw materials. In addition, the technical innovation and transformation of the existing factories using bagasse will be accelerated

bamboo raw materials

China is the country with the richest bamboo resources in the world, with 39 genera and more than 500 species. Bamboo is widely distributed in the tropics and subtropics, and is also common in temperate regions. Bamboo is also widely distributed vertically, growing on mountains from hundreds of meters to more than 3600 meters above sea level. At present, the total area of bamboo forest in China is about 3.6 million Hm2 (2000), and the average annual increase is 60000-70000 hm2. China ranks first in the world in terms of bamboo species, bamboo forest area and volume. According to preliminary calculation, China can produce about 20million tons of bamboo (air dried) every year, accounting for less than 20% of the total output for the purpose of industrial utilization, while the amount used in the pulp and paper industry is only allowed to account for about 5% (the total output of bamboo pulp in China was only 450000 tons in 2000)

bamboo fiber is a good raw material for papermaking. Its fiber length is much larger than that of common grass raw materials. The overall characteristics of bamboo fiber are between long fiber wood pulp and broad-leaved wood pulp. Bamboo fiber and some wood pulp can be used to produce high-quality paper. It can also be used to make medium and high-grade cultural paper by mixing long fiber pulp with other annual plant fibers

with the scientific planting and strengthened management of bamboo resources, the number of bamboo resources will increase. It is expected that pulping and papermaking with bamboo raw materials will have a rapid development in recent years

rice and wheat straw raw materials

rice and wheat straw raw materials are the most important non wood raw materials in China, accounting for more than 60% of non wood raw materials. However, due to technical and pollution problems, they have entered the stage of steady speed regulation. It is expected that the future work will mainly focus on the technical transformation of existing old plants to solve the pollution problem. If there are new mature technologies and equipment for pulping and papermaking with rice and wheat straw raw materials, it will create conditions for their development

5 summary

in the future, the development speed of wood pulp will be much higher than that of non wood pulp, and the absolute value of non wood pulp production will not decrease significantly in the short term. It is expected that reed pulp production will increase in recent years; The increasing rate of bagasse pulp output depends on the utilization of existing bagasse raw materials; Bamboo pulp production will have a great development; The production of rice and wheat straw pulp will focus on the technical transformation of the old plant, and the total output of straw pulp will be maintained at a certain level. If there are mature new technologies, there will be further development

Copyright © 2011 JIN SHI