Fiber separator

The raw material processed by the hydraulic pulper still contains small pieces of paper that are not completely loosened, so it must be further processed. Further processing of fiber is very important to improve the quality of waste paper pulp. Generally speaking, pulp disintegration can be carried out in the breaking process and refining process. However, the waste paper pulp has already been break down, if it is loosened again in a general breaking equipment, it will consume high electricity, the utilization rate of the equipment would be very low and the strength of the pulp is reduced by fiber being cut again. Therefore, the disintegration of waste paper should be be carried out more efficiently without cutting the fibers, fiber separator is by present the most widely used equipment for waste paper further processing. According to the structure and function of fiber separator, fiber separator can be divided into single effect fiber separator and multi-fiber separator, the most commonly used is single effect fiber separator.

The structure of single effect fiber separator is very simple. The work theory is as following: the slurry flows from top small diameter end of the cone shape shell and pumped along the tangential direction, the impeller rotation also provides pumping force which allows the slurry produce axial circulation and produce strong deep current circulation, the fiber is relieved and loosened in the gap between the impeller rim and bottom edge. The outer periphery of the impeller is equipped with a fixed separation blade, which not only promotes fiber separation but also generates turbulent flow and scours screen plate. Fine slurry will be delivered from the screen hold on the back side of impeller, light impurities such as plastic will be concentrated center outlet of the front cover and discharged regularly, the heavy impurities are affected by centrifugal force, follows the spiral line along the inner wall into the sediment port below the large diameter end to be discharged. The removal of light impurities in the fiber separator is carried out intermittently. The opening time of the discharge valve must based on the amount of light impurities in the waste paper raw material. Single effect fiber separator should ensure pulp fiber are fully loosened and the light impurities won’t be break down and mixed with fine pulp. Also the process should continuously separate plastic films and other light impurities to discharge in short time to ensure and restore the balance of the fiber separator, generally, the light impurities discharge valve automatically controlled to discharge once every 10~40s, 2~5s each time is more suitable, the heavy impurities are discharged every 2h and finally achieve the purpose of separating and cleaning pulp fibers.