| 摘要 |
<p>PURPOSE:To reduce the number of machineries to be used and to simplify maintenance and control by interposng a pressure tank having volume larger than the total volume of a plurality of air chambers and supplying compressed air to a plurality of the air chambers. CONSTITUTION:Four intermittent pneumatic water pumping-up devices 2a-2d are arranged in a lake 1 and respective air chambers are connected to a pressure tank 4 by air supply hoses 5a-5d. A compressor 6 is connected to the pressure tank 4 and pressure control valves 7a-7d are provided to the air supply hoses 5a-5d. The pressure tank 4 is formed into an automatic pressure control structure wherein the upper part tank thereof is moved up and down to change the internal volume of the tank 4 so as to be capable of always keeping almost constant pressure. By this constitution, the pressure tank 4 receives the supply of compressed air from the compressor 6 and air is sent to the respective intermittent pneumatic water pumping-up devices 2a-2d through pressure control valves 6a-6d while constant pressure is held by the automatic pressure control structure thereof to treat sewage.</p> |
