System for the treatment of sewage or the like

Claim 1

A PURIFICATION SYSTEM COMPRISING A RECIRCULATION TANK HAVING AN INLET FOR THE RECEPTION OF LIQUID TO BE PURIFIED, A LIQUID PURIFICATION UNIT, MEANS WITHDRAWING LIQUID FROM SAID RECIRCULATION TANK AND DIRECTING AT LEAST A PART THEREOF TO THE TOP OF SAID PURIFICATION UNIT, MEANS DIRECTING AT LEAST A PART OF THE EFFLUENT FROM SAID PURIFICATION UNIT BACK TO SAID RECIRCULATION TANK, INCLUDING AN UPRIGHT CONDUIT RECEIVING LIQUID FROM SAID PURIFICATION UNIT AND HAVING A DELIVERY END EXTENDING INTO SAID RECIRCULATION TANK AT A LOCATION BELOW THE TOP THEREOF, SAID UPRIGHT CONDUIT BEING OPEN TO PERMIT UNINTERRUPTED FLOW THERETHROUGH AT ALL TIMES DURING OPERATION OF THE SYSTEM, MEANS DIRECTING PART OF THE EFFLUENT FROM SAID PURIFICATION UNIT AWAY FROM SAID RECIRCULATION TANK INCLUDING A LATERALLY EXTENDING BRANCH OF SAID UPRIGHT CONDUIT HAVING ITS CONNECTION TO SAID UPRIGHT CONDUIT AT A LEVEL ABOVE SAID DELIVERY END OF SAID UPRIGHT CONDUIT AND BELOW THE TOP OF SAID RECIRCULATION TANK SO THAT THE LEVEL IN THE RECIRCULATION TANK MAY RISE ABOVE THE DELIVERY END OF SAID UPRIGHT CONDUIT TO A LEVEL ABOVE THE LEVEL OF THE CONNECTION OF SAID BRANCH TO SAID UPRIGHT CONDUIT, WHEREUPON EFFLUENT WILL BE DISCHARGED FROM SAID UPRIGHT CONDUIT THROUGH SAID LATERALLY EXTENDING BRANCH, SAID LIQUID PURIFICATION UNIT BEING A BIOLOGICAL OXIDIZER TOWER, MEANS FOR DELIVERING THE LIQUID TO BE PURIFIED INTO SAID RECIRCULATION TANK ALONG THE WALL THEREOF, AND MEANS DIRECTING PART OF THE LIQUID WITHDRAWN FROM SAID RECIRCULATION TANK BACK INTO THE SAME ALONG THE WALL THEREOF, SAID LASTNAMED DELIVERING MEANS AND SAID LAST-NAMED DIRECTING MEANS BEING ARRANGED TO CAUSE CIRCULATING MOVEMENT OF THE LIQUID IN THE RECIRCULATION TANK TO REDUCE THE POSSIBILITY OF SETTLING WITHIN SAID RECIRCULATION TANK.