Removing suspended solids from liquids

Claim 1

IN A PROCESS OF CLARIFYING A LIQUID CONTAINING SUSPENDED SOLID MATTER IN WHICH SETTLING OF THE SOLID MATTER IN THE LIQUID BEING CLARIFIED TAKES PLACE SIMULTANEOUSLY IN A LARGE NUMBER OF SHALLOW, CLOSELY SUPERPOSED SETTLING ZONES INCLINED TO THE VERTICAL SUFFICIENTLY STEEPLY THAT GRAVITY ALONE CAUSES THE SETTLING SOLID MATTER TO MOVE TOWARD THE LOWER END OF EACH SETTLING ZONE INTO A COMMON VERTICAL SETTLING ZONE COMMUNICATING WITH EACH OF THE SUPERPOSED SHALLOW SETTLING ZONES, CLARIFIED LIQUID IS WITHDRAWN FROM NEAR THE TOP OF EACH OF THE SUPERPOSED SETTLING ZONES SIMULTANEOUSLY WITH THE INTRODUCTION OF LIQUID TO BE CLARIFIED INTO SAID ZONES AND THE SOLID MATTER SETTLING TO THE BOTTOM OF THE VERTICAL SETTLING ZONE IS COLLECTED IN A SLUDGE ZONE AND DISCHARGED; THE IMPROVEMENT WHICH COMPRISES PERIODICALLY INTERRUPTING THE WITHDRAWAL OF THE CLARIFIED LIQUID FROM THE SETTLING ZONES FOR PERIODS OF TIME RELATIVELY SHORT COMPARED TO THE TIME DURING WHICH SAID SIMULTANEOUS WITHDRAWAL OF THE CLARIFIED LIQUID TAKES PLACE.