| 摘要 |
<p>MIXING OXYGEN GAS WITH MEDIUM CONSISTENCY PULP IN A PUMP DISCHARGE Oxygen delignification of paper pulp (comminuted cellulosic material in a slurry) at medium consistency (i.e., about 6-18%) is practiced without the necessity of a separate mixer. The pulp is drawn into the inlet of a fluidizing centrifugal pump capable of pumping medium consistency pulp. The pump typically has a vacuum system associated with it for effecting degassing of the pulp. As the pulp is pumped out of the pump outlet, oxygen gas is added to the pulp. This is accomplished utilizing a shear plate having a central opening and one or more radial bores, oxygen being introduced under pressure into the bores to pass into the pulp flowing through the plate central opening. A tube may be disposed in the bore(s) and have an oxygen permeable portion (such as a porous stone or sintered metal) extending into the central opening in the plate, the oxygen being introduced in the form of very small bubbles by the oxygen permeable portion.</p> |
