| 摘要 |
<p>PURPOSE:To improve the utilization efficiency and the sludge feeding-back efficiency, respectively of an air blower by switching the air blower of an aeration layer ratio to each speed of revolution being suitable for a simultaneous operation of an aeration device of an aeration tank and a sludge feeding-back air lift of a sedimenting tank, and an operation of only the air lift, respectively. CONSTITUTION:In the sewage purifying device B of an intermittent aeration type, an aeration tank 2 into which sewage is allowed to flow from an inflow tube 1 is provided with an aeration device 3 consisting of an air blower 30 for force-feeding air, a feed air tube 31 and a diffusing tube 32. In this case, the air blower 30 is used in common as an air blower for operating an air lift 6 for feeding back sludge, provided in a sedimenting tank 4. Also, to the feed air tube 31, a control valve V is connected. Moreover, a driving motor M of the air blower 30 is constituted so that is rotating speed is variable, and also this rotating speed is interlocked with an opening/closing operation of the control valve V and controlled by a control panel 7. Furthermore, the air blower 30 is controlled so as to be switched to the speed of revolution being suitable for a simultaneous operation of the aeration device 3 and the air lift 6, and the speed of revolution being suitable for an operation of only the air lift 6.</p> |
