JPH0466198A - Aerator ventilation control device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention uses a float to detect water level fluctuations in a sewage tank, etc. installed in the basement of a building, and opens and closes the ventilation of a self-priming aerator. Aerobic operation is automatically switched to anaerobic operation at low water levels to perform effective wastewater treatment, especially scum crushing.

[Conventional technology]

Wastewater and sewage generated within the building are temporarily stored in the basement of the building, and while being aerated, II! A building bit will be installed to process the air and pump it up to drain it into the sewer. In such bilbits and pump wells, the organic matter in the wastewater decomposes and ferments, producing methane gas and other harmful gases.
The wastewater is stirred and aerated to prevent bad odors. For this reason, a stirrer and an aerator are installed, and these agitators and aerators are operated continuously regardless of the water level.

[Problem that the invention aims to solve]

The aerator installed in such a building bit uses a screw that is rotated by a motor to stir the wastewater, and uses the negative pressure generated at the tip of this screw to connect the ventilation pipe to the aerator. Air is sucked in from the tank, aerated, and the scum floating on the surface of the sewage water is sucked in and crushed.

Therefore, Ii! is necessary for scum suction! It is necessary to keep the flow rate of surface wastewater into the air machine above a certain limit. However, when the water level is high, it is difficult to obtain an inflow rate higher than necessary. Also, when the water level is low, in order to draw more scum into the aerator, it is necessary to generate a swirling flow inside the bit using the inner wall of the bit, etc., and guide the scum to the vicinity of the scum suction port.

However, in conventional aeration machines that do not restrict the amount of ventilation, bubbles and the upward flow caused by the bubbles weaken the linearity of the agitated water flow, resulting in insufficient swirling flow within the bit, leaving scum at the corners. It turns out. When this scum rots, it causes a bad odor, so conventionally, it has been necessary to periodically discharge this scum using a scum discharge device installed separately from the aerator.

In the present invention, wastewater can be effectively treated with a single aeration machine by automatically switching between aeration operation, scum collection, and scum suction and crushing operation according to the water level, automatically following water level fluctuations. The purpose is to

[Means for Solving the Problems] The present invention has been made to achieve the above-mentioned object, and includes making the tip of the ventilation pipe that provides ventilation to the aerator protrude above the water surface, and having the tip of the ventilation pipe follow fluctuations in the water level. The pulp is equipped with a float that floats and sinks, and at high water levels the ventilation pipe is opened for aeration operation, and at low water levels the ventilation pipe is closed for anaerobic operation, which is automatically selected according to the water level. [Operation] A valve with a float is installed at the upper end of the ventilation pipe that ventilates the aerator, so the valve with a float automatically floats and sinks as the water level fluctuates. As a result, the valve at the tip of the ventilation pipe opens and closes automatically, and at high water levels, the valve opens due to the buoyancy of the float, allowing ventilation and aeration operation. Conversely, when the water level is low, no buoyancy acts on the valve, so the valve's own weight closes the ventilation pipe. This stops aeration and improves the linearity of the water flow generated from the Q-air machine, which has stopped aeration, and increases the swirling flow speed in the tank, so that the scum floating on the surface of the sewage water flows at a speed above a certain limit. The scum is guided to the scum suction port and crushed by suction in an aerator.

〔Example〕

The present invention will be explained below based on the illustrated embodiments.

In the figure, reference numeral 1 denotes a sewage tank for temporarily storing wastewater from a pump well or a building bit, and an aerator 2 is disposed at the bottom of this sewage tank 1.

This aeration device 2 can adopt various types of mechanisms, but in the illustrated embodiment, as shown in FIG. 23 and a rectifying tube 28.

The underwater motor 21 is driven by a hydraulic, electric, or other power source, and a similarly hollow stirring blade shaft 25 is directly fixed to a hollow motor shaft 24 of the underwater motor 21 . The stirring blade 22 is formed by integrally providing a stirring blade base body 26 having a spiral shape or other shape suitable for aeration around the outer periphery of a hollow shaft 25.

The motor shaft 24 of the underwater motor 21 is made hollow with a ventilation hole 27 having a required cross-sectional area, so that the inside of the motor shaft can be ventilated, and the underwater motor shaft 24
A ventilation pipe 23 is connected to the opposite output side, that is, the side opposite to the stirring blade, and the tip of the ventilation pipe 23 is always located above the water surface. The stirring blade shaft is connected to the motor shaft ventilation port 27 through the ventilation pipe, and the inside of the stirring blade shaft can be ventilated from the inside of the motor shaft.

Further, the stirring blade 22 is housed in a straightening tube 28 (draft tube), and this straightening tube 28 has a suction port 29 widened in a trumpet shape at the upper end, and an air outlet 30 opened in the long axis direction of the stirring blade. The sewage is sucked into the rectifying tube 28 through the suction port 29 by the rotation of the stirring blades, stirred by the blades, and then discharged into the sewage water again through the outlet.

When inhaling scum, the scum is crushed and discharged, suspended in water, and the power of the water flow is used to create a swirling flow in the tank, which makes it easier to draw the scum closer to the aerator. It is something.

Further, an opening/closing valve, that is, a ventilation control valve 3 is provided above the water surface of the ventilation pipe 23, and the opening/closing operation of this valve 3 is performed by floating and sinking a float 32 due to water level fluctuations.

As shown in detail in FIG. 1, the ventilation control valve 3 includes a bottomed cylindrical valve body 31 that fits into the straight upper end of the ventilation pipe 23, and a float 3 provided at the lower end of this body 31.
2, the buoyancy of the float 32 is determined so that the entire valve 3 floats and sinks following the water level fluctuation, and the outer peripheral surface of the valve body is provided with an intake port 3.
One or more H holes are formed, and a gasket 33 is provided on the inner top surface. Therefore, when the waste water surface of the tank is at the high water level OWL as shown in FIG. 1, the valve 3 floats due to the buoyancy of the float 32, so a gap is created between the tip of the vent pipe 23 and the top surface inside the valve. Due to the negative pressure generated in the water area at the tip of the screw due to the rotation of the screw, air is discharged through the intake port of the valve 3, the opening at the tip of the vent pipe, the inside of the intake pipe, and the tip of the screw, thereby performing the required aeration operation.

When the water level decreases and reaches a low water level, the valve 3 is lowered, the valve 3 is supported at the tip of the vent pipe, and the valve's own weight presses the gasket against the opening surface of the tip of the vent pipe to close the valve. However, when the screw is operated in this state, the aeration is stopped, so the stirring force and scum suction force are increased, and the scum floating on the surface of the waste water can be sucked, crushed, and stirred. Additionally, when the water level rises, the valve automatically rises, restarting ventilation, and switching to aeration mode.

〔Effect of the invention〕

According to the present invention, aeration is controlled by following fluctuations in water level, so when the water level is high, the same aeration machine runs the aeration operation, and when the water level is low, the aeration is stopped and the tank is rotated. It has the advantage of increasing the flow rate and scum suction power, allowing scum floating far away to be sucked into the aerator and crushed, and wastewater to be treated efficiently.

[Brief explanation of drawings]

The drawing shows an embodiment of the ventilation control device for the aerator of the present invention,
FIG. 1 is a front view showing a high water level state, FIG. 2 is a partially cutaway front view of the aerator, and FIG. 3 is a front view showing a low water level state. 1 is a tank, 2 is an aerator, 3 is a valve, 31 is a valve body, and 32 is a float. Figure 1 Figure 3 Patent applicant Hitachi Kiden Industries, Ltd. Figure 2 η

Claims (1)

[Claims] (1) In a device that aerates wastewater by stirring and aerating it, the tip of the aeration tube that aerates the aerator is made to protrude above the water surface, and at the tip of this aeration tube there is a valve with a float that rises and falls according to changes in the water level. A ventilation control device for an aerator, characterized in that the ventilation pipe is opened at a high water level to perform aeration operation, and the ventilation pipe is closed at a low water level to perform anaerobic operation.