| 摘要 |
<p>PURPOSE:To prevent the rise in a water level owing to progression of clogging by providing a detector for the watr level in a tank and a device for diffusing gas into an outflow pipe and controlling the flow rate of said gas, and changing the flow rate of the gas into a water flow pipe according to a change in the water level. CONSTITUTION:When the operation of a cleaning up tank is continuously performed, the clogging in a packing material 3 is progressed by thickening of biological membrane and the water level in the tank rises graudally until the level arrives at a preset position, then a water level controller constituted of the 2nd air diffuser 15, a flow rate regulating valve 16 and a float 17 operates to maintain the water level. More specifically, the 2nd air diffuser 15 has the function of an air lift pump together with an outflow pipe 6, and the suction power thereof increases or decreases according to the flow rate of the gas diffused from the diffuser 15. When the water level rises to lift the float 17, the valve 16 is opened and the gas is discharged from the diffuser 15 to suck and discharge treated water 5.</p> |
