HD cleaner is the use of fibers and impurities in different proportions to separate the impurities .The slurry at a certain pressure from feed three tangent enter slag separator before high rotation speed, due to the different centrifugal force, heavy impurity is thrown to the wall .under the action of gravity, gradually to the bottom of the cone operation, into the sediment cans. Because of small centrifugal force, Fiber gradually run into the center the low pressure area, to scroll up after the bottom, and finally discharge by good pulp mouth .A high concentration of removing the dregs device in addition to with certain taper cone, and the cone is long, pulp in the cone in decreasing the rotation radius, avoid pulp flowing in the process of reducing speed, ensure that the centrifugal force is strengthened, and improve the efficiency of purification for paper .The bottom water pressure balance is slightly bigger than pulp pressure, so that fiber can’t go into the tank bottom, only sand ,metal particles, glue, piece of plastic ,and other heavy impurity sink into the pot, reducing the loss of fiber.