| 摘要 |
<p>That part of a suspension produced in the pulper (1) which still contains a considerable amount of both coarse and fine impurities having a large surface area is fed through a secondary outlet (13) to a unit (4) which has a basically cylindrical housing. The stock inlet is located centrally on one end face of the unit (4) while the opposite end face is equipped with a rotor (43) turning in the axis of rotational symmetry of the housing, together with a main outlet (46) for the suspension, which outlet is attached tangentially to the surface of the housing and located on the end face where the rotor (43) is arranged. The rotor (43) produces a whirl-pool effect inside the unit (4), which has an area of low pressure at its centre. As a consequence of the whirl-pool effect in the suspension, further disintegration of the waste paper takes place. During this operation, a valve (9) located in the feed pipe or discharge pipe of the unit is closed. If this valve (9) is opened, the rotor (43) pumps the suspension out of the unit (4) and simultaneously draws in fresh suspension from the pulper (1). This procedure is repeated at regular intervals. In this manner no relatively large quantities of contaminants can any longer accumulate in the pulper (1), which might interrupt the operation of the pulper.</p> |
