JP2002018252A - Aerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aerator capable of performing efficient aeration by allowing air bubbles to reach the bottom part of a water tank by obtaining a large flowing amount of water without increasing power even in the deep water tank having a rectangular shape, or the like. SOLUTION: In the aerator wherein a hollow shaft 1 which has a screw 2 at the lower end thereof and rotationally driven by a motor 4 is arranged almost vertically, a ratio of the diameter D of the screw and the inner diameter (d) of the hollow shaft is set to 3.0 or more and the number of rotations of the hollow shaft 1 is set to 1,200 rpm or less.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aerator, and more particularly to an aerator for draining sewage and sewage into a deep water tank such as a rectangle for aerating the sewage or sewage without increasing power of the aerator. The present invention relates to an aerator capable of performing efficient aeration.

[0002]

2. Description of the Related Art Conventionally, there is an aerator disclosed in Japanese Patent Publication No. 56-21452 for aerating sewage and sewage flowing in a sewage treatment plant and a sewage treatment plant. As shown in FIG. 2, this aerator has a screw at the lower end, and a hollow shaft driven and rotated by a motor is installed substantially vertically. Agitating the treated water in the water tank with the generated flow velocity, a downward water flow is generated, and the bubble-like air sent into the water is transported to the water flow to the bottom of the tank for aeration. .

[0003]

By the way, in this aerator, a small diameter screw is rotated at a high speed to generate a water flow, and the aerator is more effectively aerated in a narrow region of a bubble discharge port at the tip of the screw. To release a lot of air so as to perform, the bubbles released into the water become gradually larger bubbles by integrating by the action of the surface tension in this released narrow water area, Due to the large buoyancy effect of these large bubbles, the buoyancy of the bubbles is larger than the water flow generated by the screw and floats on the water surface, the bubbles do not reach the bottom of the water tank, and the aeration of a deep water tank is efficiently performed. There was a problem that it was not possible.

In order to cope with this, if the flow rate of the water flow generated by the screw is made high enough to overcome the buoyancy of the bubbles, the bubbles theoretically ride on the water flow and reach the bottom of the water tank. However, in actuality, the water flow from the screw spreads around it, so the flow velocity decreases as the water depth increases, so that bubbles do not reach the bottom of the water tank for the power consumed, and effective aeration can be performed Did not.

The present invention has been made in view of the above-mentioned problems of the conventional aerator, so that a large amount of flowing water can be obtained without increasing power even in a deep water tank such as a rectangular one, and bubbles are transferred to the bottom of the water tank. It is an object of the present invention to provide an aerator that can achieve efficient aeration.

[0006]

In order to achieve the above object, an aerator according to the present invention is provided with a screw at a lower end, and a hollow shaft rotatably driven by a motor is installed substantially vertically. , The ratio of the screw diameter to the inner diameter of the hollow shaft is set to 3.0 or more, and the rotational speed of the hollow shaft is set to 1
It is characterized in that it is set to 200 rpm or less.

In the aerator of the present invention, since the ratio of the screw diameter to the inner diameter of the hollow shaft is set to 3.0 or more, the screw outlet area with respect to the air amount increases, and a large amount of flowing water is obtained. The air bubbles released into the water are hard to be integrated, the air bubbles can be sent to the bottom of the water tank without floating on the water surface, and the rotation speed of the hollow shaft can be set to 1200 rpm or less. Along with this, aeration can be efficiently performed even in a deep water tank such as a rectangle without increasing power.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the aerator according to the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the aerator of the present invention.
The aerator B is installed, for example, in a rectangular deep water tank A for treating sewage and sewage, and is supported above the water tank A by a frame or the like.

In the aerator B, the hollow shaft 1 is rotatably and substantially vertically disposed on the main body frame F via the bearing 3, and a screw 2 is provided at the lower end of the hollow shaft 1. .

The hollow shaft 1 transmits the rotation of the motor 4 to the screw 2 and feeds the air into the water. The length of the screw 2 is determined so that the screw 2 reaches a predetermined water depth. The pipe joint 1 as in this embodiment or this embodiment
Two or more cables are connected via the cable 1 to have a predetermined length.

The body frame F has a screw 2
A motor 4 or a motor with a speed reducer for rotating the motor is mounted, and the motor 4 and the hollow shaft 1 are decelerated as required through a power transmission mechanism 5 such as a gear, a chain, and a belt. To transmit power.

An air supply pipe 7 is connected to the upper end of the hollow shaft 1 via a rotary joint 9 such as a swivel. This air supply pipe 7
, A valve 8 is attached so that air supply and air supply stop can be selectively performed. Then, an air blower 6 or a pressure air supply source is connected to the air supply pipe 7, and when the valve 8 is opened, air is supplied from the blower 6 or the pressure air supply source to supply the screw 2 in the water. Hollow shaft 1 in the water area at the tip
Air is blown out from the shaft end as small bubbles and sent into water.

The screw 2 is composed of one or a plurality of blades attached to the shaft end of the hollow shaft 1, and as shown in FIG. 1, the ratio D / d of the screw diameter D to the inner diameter d of the hollow shaft 1.
Is set to 3.0 or more. Thus, the screw diameter D
Is increased in proportion to the inner diameter d of the hollow shaft 1, the outlet area of the screw 2 with respect to the air amount is increased, and a large amount of flowing water can be obtained. It is difficult to integrate, and a sufficient downward flow reaching the bottom of the water tank A can be obtained even if the water flow is not fast, and the rotation speed of the hollow shaft 1 by the motor 4 is 1
Even if it is set to 200 rpm or less, bubbles can be sent to the bottom of the water tank A without floating on the water surface, and even in a deep water tank A such as a rectangle, aeration is efficiently performed without increasing power. Can be done.

Next, the operation of the aerator B will be described.
The air supplied from the blower 6 via the air supply pipe 7 and the valve 8 is supplied to the hollow shaft 1 through a rotary joint 9 such as a swivel at the shaft end of the hollow shaft 1. The air supplied to the hollow shaft 1 is micronized by a screw 2 provided at the lower end of the hollow shaft 1 and released into water.

At this time, since the screw diameter D is set to be large in proportion to the inner diameter d of the hollow shaft 1, the outlet area of the screw 2 with respect to the air amount increases, and
A large amount of flowing water can be obtained, and bubbles released into the water are hardly integrated, and a sufficient downward flow reaching the bottom of the water tank A can be obtained, and the rotation speed of the hollow shaft 1 by the motor 4 can be reduced. Even if it is set to 1200 rpm or less, air bubbles can be sent to the bottom of the water tank A without floating on the water surface, and even in a deep water tank A such as a rectangle, aeration is efficiently performed without increasing power. be able to.

[0017]

According to the aerator of the present invention, since the ratio of the screw diameter to the inner diameter of the hollow shaft is set to be 3.0 or more, the screw outlet area with respect to the air amount increases, and the screw exit area increases. The amount of flowing water can be obtained, and the air bubbles released into the water are hard to be integrated, the air bubbles can be sent to the bottom of the water tank without floating on the water surface, and the rotation speed of the hollow shaft is 1200 rpm or less. Along with the setting, aeration can be efficiently performed without increasing power even in a deep water tank such as a rectangle, and the cost of aeration treatment of sewage and sewage can be reduced.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of an aerator according to the present invention.

FIG. 2 is a front view showing a conventional aerator.

[Explanation of symbols]

 A water tank B aerator F body frame 1 hollow shaft 2 screw 3 bearing 4 motor 5 power transmission mechanism 6 blower 7 air supply pipe 8 valve 9 rotary joint

Continued on the front page (72) Inventor Manabu Takeuchi 3-11-1, Shimosakabe, Amagasaki-shi, Hyogo F-term (reference) in Hitachi Kiden Kogyo Co., Ltd. 4D029 AA09 AB06 4G035 AB10 4G037 AA01 EA04 4G078 AA01 AB20 BA05 CA12 DA19 DC10 EA10

Claims (1)

[Claims] An aerator provided with a screw at a lower end and having a hollow shaft rotatably driven by a motor installed substantially vertically, wherein a screw diameter (D) and an inner diameter (d) of the hollow shaft are provided.
A ratio of (D / d) is set to 3.0 or more, and the rotation speed of the hollow shaft is set to 1200 rpm or less.