| 摘要 |
<p>Continuous process comprises a pre-purification equipment with a retaining space, a bacterial bed sprayed by means of pumps and a post-clarification tank with a return device for diluting the incoming material to the bacterial bed; it is controlled by a time-switch for the pumps so that the retaining space will successively be filled and emptied during a certain interval of time, e.g. one day. Difficult estimations of the pumping and non-pumping periods, with possibly erroneous results, are avoided and simple and optimum regulation of the plant can be achieved. The post-clarification tank is provided with an elevator tube with an inlet at the lowest point of the funnel-shaped tank; it serves for recycling a sludge-water mixt. towards the pre-purification equipment. A plunger-electromagnet has a piston which opens and closes the outlet openings drilled in the elevator tube. Recycling is effected by an excess water pressure when the surface of the water is maintained at a level higher than that in the mechanical pre-purificn. equipment. A control device enables a suitable relationship to be established between the amt. of water retained and that recycled.</p> |
