JPH057889A - Aerating and agitating device - Google Patents

Abstract

PURPOSE:To prevent the deposition on a hollow shaft and to perform aeration and agitation over a long period using this device with its wear reduced and capable of being easily assembled by utilizing a minute gap generated by deforming a Z-shaped seal with the pressure difference. CONSTITUTION:A hollow shaft 2 with a screw 3 provided at its lower end is directly connected to a hollow motor shaft, and a control valve 5 for adjusting the air passage is furnished on the unloaded side of the motor shaft 11 and a Z-shaped seal 4 at the end of the motor shaft 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aeration and agitation device for sewage treatment which effectively performs low load operation at the start of aerobic / anaerobic operation and removal of nitrogen in sewage.

[0002]

2. Description of the Related Art As a treatment method for removing organic substances in wastewater, there is a method of agitating wastewater and aerobically treating it by aeration. However, the conventional screw-type aerator with a controllable air flow rate does not have a problem during aerobic operation, that is, during aerobic operation in which air is supplied to the wastewater to decompose and treat organic substances in the wastewater. When ventilation is stopped, the negative pressure inside the hollow shaft sucks up dirty water into the hollow shaft and closes the hollow shaft due to dirty water.Therefore, an oil seal or the like is used to seal between the rotating motor hollow shaft and the fixed side parts. Further, a minute hole is provided, and a small amount of air is made to flow from this minute hole to cope with the problem. Further, as shown in FIG. 3, minute holes are provided in the connection flange 7A, and a seal 4A is provided on the inner circumference of the motor casing 12A.

[0003]

When an oil seal is provided between the hollow shaft of the motor and the stationary member, the negative pressure of the hollow shaft increases the surface pressure of the seal and causes the seal and the contact thereof. Parts are heavily worn and need frequent replacement and repair. Further, when a labyrinth is used, the clearance of the labyrinth is limited due to the runout of the shaft, and the machining accuracy and adjustment are very severe.

The present invention utilizes the characteristics of the Z-shaped seal that is deformed due to the pressure difference and produces a minute gap, which is less worn, is easy to assemble, prevents deposits on the hollow shaft, and is replaced. -The purpose is to perform a maintenance-free aeration stirring operation that does not require repair for a long period of time.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above object. A hollow motor shaft is directly connected to a hollow shaft having a screw at its lower end, and the motor shaft has an anti-load. The gist is that a control valve for adjusting the ventilation amount is provided on the side and a Z-shaped seal is provided at the end of the hollow shaft.

[0006]

When the motor 1 rotates the screw 3 at the tip of the shaft through the hollow shaft 2, the waste water is agitated and the negative pressure generated by the propulsive force of the screw in the waste water causes a negative pressure of the motor directly connected to the hollow shaft. Air is sucked from the side opposite to the output shaft side of the hollow shaft and sent out into the water through the hollow shaft. At this time, the air amount is adjusted by opening / closing the control valve 5 provided on the intake side. Even if the control valve 5 is completely closed, since the Z-shaped seal 4 is provided on the inner circumference of the casing, a small amount of air is sucked through the gap created by the pressure difference between the Z-shaped seal and the hollow shaft. It is always filled with air, the invasion of dirty water into the hollow shaft is prevented, and sludge and the like does not adhere and accumulate in the hollow shaft, so that smooth driving can be performed even when switching to aerobic operation. The Z-shaped seal can be combined in quantity and direction depending on the amount of micro air.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the embodiments shown in FIGS. As shown in FIG. 1, a screw type self-priming aerator A used for treating sewage such as sewage and industrial wastewater has a motor 1 and a hollow motor shaft 1 of the motor 1.
1, a hollow shaft 2 of a required length directly connected to the screw shaft 1, a screw 3 provided at the tip of the hollow shaft 2, a Z-shaped seal 4 provided on the opposite side of the motor shaft 11, and a control valve 5 for controlling the air flow rate. Composed.

The hollow shaft 2 has a required length and strength, and when the aeration device A is arranged in an aeration tank or a water channel so as to have a required penetration angle with respect to the sewage surface, a predetermined depth from the water surface. The length is appropriately determined so as to reach, and the screw 3 is fixed to the tip.

A motor shaft 11 of the motor 1 is connected to the base end side of the hollow shaft 2 via a shaft joint 6, and the screw 3 is rotated by the drive of the motor 1 via the hollow shaft 2 to remove waste water. so,
In addition, a negative pressure is generated in the water area at the tip of the screw, and this negative pressure is used to supply air as fine bubbles to the water area at the tip of the screw through the hollow motor shaft 11 and the hollow shaft 2. In this case, although not shown in the drawings, an electric control circuit may be provided in the motor 1 so that the rotation speed of the motor is controlled to adjust the rotation speed of the screw so that aeration and stirring can be adjusted.

The motor shaft 11 is rotatably supported by a casing 12 of the motor 1 via bearings 13 and 13, a connecting flange 7 is connected to the casing 12, and the inner periphery of the casing 12 is Z-shaped. A shape seal 4 is provided. Further, a control valve 5 is provided on the connection flange 7, and the control valve 5 is electrically operated to open and close to adjust the ventilation amount. The control valve 5 is set to have the ventilation amount set during the aerobic operation set at the previous time and can be adjusted according to the load, and is fully closed or close to the fully closed state during the anaerobic operation.

Therefore, in the apparatus constructed as described above, when the screw 3 at the tip of the rotating hollow shaft 2 driven by the motor 1 is submerged in water, it is directly connected to the hollow shaft by the negative pressure generated by the propelling force of the screw. Air is sucked in from the side opposite to the output shaft side of the hollow shaft of the motor and sent out into the water. The amount of air is adjusted by opening / closing the control valve 5 such as an electric ball valve provided on the intake side. At this time, the valve to be used may be manual, electric, or any model, and the aeration amount can be adjusted by adjusting the time schedule of the opening time and the closing time for a valve such as a solenoid valve whose intermediate opening and closing adjustment is difficult. When the valve is fully closed, the Z-shaped seal 4 is deformed by the pressure difference between the left and right, and a minute amount of air is supplied into the water through the gap generated at that time. At this time, the direction and quantity of the Z-shaped seal are adjusted according to the required air volume. On the other hand, conventionally, FIG.
As described above, the connection flange 7A is provided with a minute hole, the motor casing 12A is provided with the seal 4A on the inner circumference, and when the valve is fully opened, a minute amount of air is supplied into the water through the minute hole.

[0012]

When the control valve is fully closed during anaerobic operation, the hollow shaft is sucked through the gap due to the deformation of the Z-shaped seal, so that the hollow shaft is filled with air and sewage enters the hollow shaft. Since it does not invade, sludge etc. does not adhere and deposit inside the hollow shaft, it can be driven smoothly even when switching to aerobic operation, and there is no wear part compared to the conventional combination of micro holes and seals, and maintenance Will be much easier.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view of an aeration and agitation device of the present invention.

FIG. 2 is an enlarged cross-sectional view of a main part.

FIG. 3 is an explanatory diagram of a main part structure conventionally considered by the inventors.

[Explanation of symbols]

 1 Motor 11 Motor Shaft 2 Hollow Shaft 3 Screw 4 Z Type Seal 5 Control Valve 4A Seal 4B Labyrinth

Claims (1)

Claim: What is claimed is: 1. A hollow motor shaft is directly connected to a hollow shaft having a screw at a lower end thereof, and a control valve for adjusting a ventilation amount is provided on an anti-load side of the motor shaft. An aeration agitator characterized in that a Z-shaped seal is provided at the motor shaft end.