| 摘要 |
PURPOSE:To make improvement in the capacity to discharge sewage by stopping a vacuum pump and driving a discharge pump to discharge the sewage when the sewage in a strainer box attains a prescribed volume, then stopping the discharge pump and driving the vacuum pump. CONSTITUTION:To vacuum pump 11 connected to the discharge port side of a liquid sealing valve 9, the discharge pump 14 connected to a piping 13 provided in the bottom of the strainer box and a 2nd pressure switch 16 connected to the discharge port side of the pump 14 are provided. The sewage in the tank 1 is introduced into the box 7 by the negative pressure in the box 7 generated by the driving power of the pump 11. The vacuum pump 11 is stopped and the discharge pump 14 is driven by the operation of the 1st pressure switch 10 to discharge the sewage in the box 7 when the sewage in the box 7 attains the prescribed volume. The pump 14 is stopped and the pump 11 is restarted by the drop of the discharge pressure by the pump 14. Consequently, the capacity to discharge the sewage in the tank 1 is improved in this way. |
