Raw material for fiberboard

The basic unit of fiberboard is separated wood fibers or fiber bundles. The raw materials for making fibers mainly come from forest logging residues, such as branches, tips, small-diameter wood, etc.; and wood processing residues, such as board edges, shavings, sawdust, etc. In addition, waste materials from chemical processing of forest products (such as tannin extract and hydrolyzed residues) and other plant stems can be used to make fibers. Softwood has a high fiber content, and the fiber length is 30-50% longer than that of hardwood. If hardwood is used, it needs to be processed first: it can be mixed with coniferous and hardwood to make pulp, or use chemical methods to treat wood chips, or hot water and steam can be used. Before fiber separation, the raw material is cut into thin slices of 20-30 mm in length, 3-5 mm in thickness and 15-25 mm in width with a chipper. If the wood chips are too large, it is difficult to soften or soften unevenly during the preheating and refining process, and the degree of fiber separation is small; if the wood chips are too short, the proportion of cut fibers will be large and the interweaving performance will be poor, resulting in a decrease in the strength of the fiberboard. The cut wood chips are screened, shredded, washed with water and then sent to the silo for fiber separation.