GB1418348A - Method and apparatus for sewage treatment - Google Patents

Abstract

1418348 Sewage treatment MASCHINENFABRIK HELLMUT GEIGER GmbH & CO KG 19 July 1973 [20 July 1972] 34505/73 Heading C1C A sewage percolating tank of the kind which is charged with the sewage and supplied with air for promoting organic growth in the charge, wherein said tank contains plate means for supporting a growth coating and movable stripping means capable of mechanically detaching the growth coating. In operation, the tank is charged with the sewage and supplied with air and the organic growth mass is mechanically detached from the surfaces before said mass reaches the stage where it automatically detaches itself due to its biological and/or physical action. In the embodiment of Fig. 1 a charging device 2 is arranged in a casing 1 above rectangular parallel plates 3. Sewage enters at 2 and flows through the plates, over the inclined base 4 and out of the drain 5. The air enters at 6 and leaves at 7. The plates 3 are separated by spacing members 8 and are mounted in a hinge joint 9. A stripping device 11 is rotatably mounted at 12. In normal operation the plates 3 and device 11 occupy the positions shown in full lines. In order to detach the growth coating, the device 11 may be rotated to position 13 thus stripping half of the plate 3 and the plate may be rotated to position 10, stripping the other half of the plate. When both plate and device 11 are in the positions shown in dotted lines they form an inclined surface down which sludge settles to be removed through access plate 14. The sludge has low water content and in most cases sedimentation is unnecessary. In another embodiment, Fig. 2 (not shown) the plates themselves form the stripping device, two sets of interlocking plates being provided, each in a comb formation. Preferably no liquid is delivered to the tank during stripping, which may be automatically controlled.