| 摘要 |
<p>521,036. Treating sewage; filters. GRIFFIN, J. D. March 28, 1939, No. 9726. Convention date, March 29, 1938. [Classes 46 and 111] The gases formed in the anaerobic digestion of sewage are separated therefrom by subjecting the liquid, while in a finely divided state, to reduced pressure. With apparatus as shown in Fig. 1, a pump 7 forces liquid, from the top of a closed digestion tank 2 through a pipe 4 and float controlled valve 10 into a second tank 3, kept under reduced pressure by means of a fan 14. The liquid is dispersed by a rotating disc 11, trickles over filling-material 13, collects at the bottom of the tank and is returned by the pump 7 to the tank 2. Fresh liquid enters by a pipe 19. Matter settling in the tank 2 may be discharged through a pipe 16. A pipe 18 is provided for the discharge of treated liquid or of matter settling in the tank 3. As shown in Fig. III, the upper part of the digestion tank is provided with a gas-exhausting device 12 and liquid withdrawn from the lower part of the tank by the. pump 7 is returned to a sprayer 23 and distributed over a trickling filter 27 charged with anaerobic organisms.</p> |
