Papermaking raw materials mean the materials for paper and pulp process, mainly include plant fiber and non-plant fibers like inorfil, chemical fiber, and metal fiber. The fiber material of papermaking selection is decided by the paper quality requirement and working condition of real production. From now on, the most of papermaking raw materials is plant fiber in the international market. For some developing countries, the hardwood and softwood take 95% of whole raw materials of papermaking. In China, we also mainly adopt six kind s of plant fiber, such as softwood, hardwood, straw, bast fiber, hull fiber, and waste paper fiber.
CNBM is a paper and pulp making machine manufacturer from China. We can supply solutions for wood pulp making, bamboo pulp making, bagasse pulp making and other plant fiber pulp processing. We also provide related equipment for chemical pulping including pulp digester, vacuum drum washer, twin roll press, blow tank and etc.
Softwood and hardwood
Wood is the most common materials for paper pulping. Generally, the wood is processed into wood chips and wood chips are applied to pulp and paper production. Wood log and used wood both can be used to process paper pulp.
Softwood
As the name suggested, softwood is soft and long-fiber, representative plants include cypress, larch, Korean pine, Masson pine, tomicus piniperda, Mongolian pine and etc.
Hardwood
The leaves of hardwood are wide and hard. In the paper pulp production, the pulp mill usually adopts soft kind like poplar, birch, eucalyptus and etc.
Features of wood pulp processing
- Classify the wood in the stacking for continent.
- Peeling the fresh cut wood logs can reduce the loss of materials.
- Storage the logs with resin rich after peeling.
- Wood chips are easy to pollute, after long-term storage, washing the chips before using. Besides, long-term storage of wood chips will reduce the quality.
Straw
Although the wood is the most widely used material, straw also should be noticeable in the paper pulp processing. Common straw fiber for papermaking includes reed, bamboo, straw, rice husk, Mans stalk, Chinese alpine rush, sorghum stalk, bagasse and so on. Straw fiber is short and thin, it has high content of parenchyma cell, silicon, diffluent lignin, and hemicellulose. So the quality of straw pulp is unstable and its alkaline recovery is difficult. Besides, the straw pulp is relatively difficult to manufacture paper. What’s more, some kinds of straw pulp processing also have grave pollution problems, related clean technology is required.
Bast fiber
Bast fiber plays a necessary role in paper and pulp industry not only because it is resourceful. Moreover, it is talented in the paper manufacturing, such as long and thin, high pureness, high quality, etc. common bast fiber includes hibiscus cannabinus, flax, jute, kenaf, ebony bark, mulberry bark and cotton stalk bark, etc. Take cannabinus as an example, it has similar performance like softwood in the pulping process. Because bast fiber has good stability and corrosion, it can be applied to manufacture Chinese art paper, print paper, writing paper, cigarette paper, security paper and so on.
Hull fiber
Common hull fibers include cotton, linters, cotton rag, etc. Hull fiber contains more pure cellulose, it is long, thin, whippy, tough and durable, also has good absorbency. The paper made from cotton pulp has high opaqueness, and it is soft and preservable. Virgin cotton pulp can apply for making vulcanized fibre paper and body paper. The bleached cotton pulp can apply for filter paper, waterleaf base paper, drawing paper, security paper and text paper.
