JPS6345273B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, a flow path for a liquid to be treated is formed between an inner casing and an outer casing, an oxygen-containing gas is injected into the flow path, and a flow path for a liquid to be treated is formed between an inner casing and an outer casing. It relates to an aeration device that is provided with an impeller for transporting a liquid.

Various such aeration devices are known. For example, a typical conventional aeration device B shown in FIG. It is now used by hanging it and installing it on the bottom of the aeration tank. Since the aeration device B is used in liquid in this way, the submersible motor 5 is used as the motor of the drive unit A, and the impeller 4
is rotated by an underwater motor 5 via a transmission part 3. The casing part C consists of an inner casing 6 and an outer casing 7,
A flow path 8 is formed between these two casings 6 and 7. Both of these casings 6, 7 are expanded downward in diameter in a tapered manner.

In the aeration device B configured in this way, when the submersible motor 5 is started, the impeller 4 is driven to rotate, and the liquid to be treated is sucked in from the suction port 9 above the flow path 8, and then radially outward. It is designed to be discharged from the discharge port 10 to. An appropriate number of aeration tubes 11 protrude from the flow path 8, so that oxygen-containing gas, such as air, supplied from the supply tube 12 is injected from the aeration tube 11 into the liquid to be treated via an annular collecting tube 13. It's summery.

By the way, in conventional aeration equipment having such a structure, various solid substances flow into the aeration tank, especially in the aeration tank for sewage treatment, along with the sewage.
These solid substances adhere to the impeller 4 and often cause operational troubles. In particular, if a solid object such as a piece of wood gets caught in the gap between the impeller 4 and the outer casing 7, the power consumption of the submersible motor 5 increases, sometimes exceeding the motor's rated power, and the submersible motor 5 may stop. be.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an aeration device that can reduce the adhesion of solid matter to an impeller, and in particular can prevent solid matter from being caught between the impeller and the casing. .

According to the present invention, an annular ring having an outer diameter equal to or slightly smaller than the outer diameter of the impeller is attached to the inside of the outer casing immediately before the upstream side of the impeller disposed in the flow path of the liquid to be treated.

An embodiment of the present invention will be described below with reference to FIG. In FIG. 2, the same components as those of the conventional aeration device shown in FIG. 1 are designated with the same reference numerals.

An impeller 4 is disposed in a channel 8 through which the liquid to be treated flows, and a suction port 9 is formed at the upper end of the channel 8, as in the conventional example. According to the present invention, a ring 14 is attached to the inside of the outer casing 7 of the impeller 4, as shown in FIG. This ring 1
The inner diameter of the impeller 4 is equal to or slightly smaller than the outer diameter of the impeller 4. With this configuration, solid objects such as pieces of wood will not get stuck in the gap 15 between the outer casing 7 and the outer periphery of the blades of the impeller 4.

When attaching the ring 14 to the outer casing, the ring 14 is either molded integrally with the outer casing, or molded separately and then attached integrally. Additionally, the ring 14 may be formed to break in order to protect the impeller when a particularly large external force is applied.

The aeration device according to the present invention is configured as described above, and when the submersible motor 5 is started, the waste water that is the liquid to be treated is purified as described above. Since an annular ring 14 is formed inside the outer casing of the flow path immediately in front of the side, solid objects such as pieces of wood flowing along the inside of the outer casing collide with this annular ring 14 and push the impeller from the inside in the radial direction. Therefore, no solid matter is trapped between the outer casing 7 and the outer periphery of the impeller blades. Therefore, the aeration device can be stably and continuously operated without causing any motor trips, and the reliability of the aeration device can be significantly improved. Also, ring 1
4 need only be simply added to the inside of the casing, so it can be applied to conventional devices as well. Furthermore, the ring may be made of the same material as the casing material, but for example, an elastic body with relatively low elasticity may also be used.

Further, the ring may be mounted so as to be 6 to 8 mm above the inner wall of the casing, thereby further reducing the amount of solid matter approaching the tip of the blade.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional side view of a conventional aeration device, and FIG. 2 is a side view similar to FIG. 1 showing an embodiment of the present invention. 4... Impeller, 6... Inner casing, 7... Outer casing, 8... Channel, 9... Suction port, 14... Circular ring.

Claims (1)

[Claims] 1 A flow path for the liquid to be treated is formed between the inner and outer casings, an oxygen-containing gas is injected into the liquid to be treated, and an impeller is provided in the flow path to send the liquid to be treated. In the aeration device,
An aeration device characterized in that a ring whose inner diameter is equal to or slightly smaller than the outer diameter of the impeller is attached to the inside of the outer casing of the flow path immediately before the upstream side of the impeller.