摘要 |
<p>A pumping system (10) is capable of handling a paper pulp suspension of medium consistency (e.g. about 8-15% solids consistency) utilizing a conventional centrifugal pump (12). A conventional pump system capable of handling 3-8% consistency pulp may be retrofit to handle 8-15% consistency pulp. A tube (30) with vanes (33), and having an open end (37), extends through the inlet (15) to the pump so that there is a small clearance (35) between the vanes and the inlet, and so that the open end is adjacent but spaced from the hub (18) of the pump impeller (17). A gas passage (48) extends from the hollow interior of the tube to an area remote from the pump. The tube is rotated in a direction of rotation opposite to the direction of rotation of the pump impeller, and at a speed sufficient to fluidize pulp of about 8-15% consistency, and to force the pulp toward the pump. Gas which collects at the pump impeller is withdrawn through the tube and the gas passage in a shaft (39) connected to the tube, and for that purpose a vacuum pump (52) may be utilized.</p> |