JPH059128B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a device for mixing and stirring a gas into a solid-liquid mixture in processes in all industrial fields including sewage treatment facilities and waste paper deinking devices. That is, it relates to an aeration device.

[Prior Art] A conventional aeration device sucks in a solid-liquid mixture to be treated from a suction port of a casing by rotating an impeller, and also supplies gas from the outside through a gas supply pipe to the impeller. The gas was blown out into the solid-liquid mixture from a gas outlet formed on the upstream or downstream side of the vehicle. As a result, a large number of fine gas bubbles are formed in the solid-liquid mixture to perform aeration, and the solid-liquid mixture is discharged from the discharge port of the casing.

[Problems to be Solved by the Invention] As a result of various studies, the inventor found that the conventional aeration device has the following problems. That is, for example, when an aeration device is used as a waste paper deinking device, the solid-liquid mixture is violently undulating near the gas outlet due to the jet of gas, so the solid-liquid mixture forms on the wall near the gas outlet. When the solid component in the mixture adheres and comes into contact with the blown gas, it dries rapidly and sticks to the wall surface, making it impossible to remove it. Then, by continuing to operate the aeration device, such solid components adhere to the wall surface repeatedly, and a fixed substance consisting of solid components grows. As a result, the gas outlet is blocked by the grown solid matter, which prevents the gas from blowing out into the solid-liquid mixture, reducing the aeration performance of the aeration device, that is, the mixing and stirring efficiency of fine gas bubbles. This will reduce the diffusion efficiency of the gas bubbles. A problem arises in that the gas must be supplied at high pressure. In particular, if the gas supplied from the outside is dry, its temperature is high, and the blowing speed at the gas outlet is fast, the growth rate of fixed substances is also fast, and even if the aeration equipment is operated for only a short period of time, the gas blowing It was found that the exit was blocked. Furthermore, since it is necessary to clean the air outlet to remove stuck substances, the operation of the apparatus must be frequently interrupted.

The present invention was created in view of the problems of the prior art, and it is possible to maintain a predetermined aeration performance without clogging the gas outlet even after long-term operation. The purpose is to provide an aeration device that can.

[Means for Solving the Problems] The aeration device of the present invention is an aeration device that blows out gas supplied from the outside into a solid-liquid mixture from a gas outlet, and mixes liquid or vapor with the gas supplied from the outside. A mechanism is in place.

Here, the mixing mechanism is configured by, for example, connecting a liquid mixing pipe or a vapor mixing pipe to a gas supply pipe that supplies gas from the outside to the aeration device or a gas chamber provided in the aeration device. can do.

When carrying out the present invention, the mixing mechanism is provided at a position that prevents liquid or vapor from flowing back toward the gas supply source when the gas supply source is stopped;
Preferably, a check valve is provided in the mixing mechanism or gas supply pipe.

[Function] According to the aeration device of the present invention, the mixing mechanism mixes the externally supplied gas and the liquid or vapor to form a liquid-mixed gas or moist air, and the solid-liquid mixture is released from the gas outlet. It is squirted inside.

The solid component of the solid-liquid mixture adhering to the wall surface does not dry even if it comes into contact with the liquid-mixed gas or humid air, so the solid component does not stick to the wall surface and no solid matter grows. Furthermore, the liquid mixture gas or humid air blown out from the gas outlet blows off the stuck substances on the wall surface and peels them off, so that the gas outlet is completely prevented from being blocked by the stuck substances. Therefore, even if the aeration device of the present invention is operated for a long period of time, its aeration performance will not deteriorate.

Furthermore, gas can be supplied under constant pressure, eliminating the need for high pressure. Moreover, continuous operation can be performed for a long period of time without interrupting the operation of the apparatus for cleaning.

[Example] Hereinafter, an example of the present invention will be described with reference to FIGS. 1 and 2.

In FIG. 1, an aeration device, generally indicated by the reference numeral 10, is housed in an aeration tank 12, which contains a solid-liquid mixture A to be aerated.

The aeration device 10 includes a casing 14,
A suction port 16 for the solid-liquid mixture A is provided above the casing 14, and a discharge port 18 that opens toward the outer circumference is provided below. An impeller 20 is housed inside the casing 14.

A gas chamber 22 is formed in the lower central portion of the casing 14, and a plurality of gas outlets 24 open toward the discharge port 18 at the radially outer side of the gas chamber 22. Further, the gas chamber 22 is connected to a gas supply pipe 26 connected to a gas supply source (not shown).
A liquid injection pipe (or steam pipe) 28 is further connected to this gas supply pipe 26 at a confluence point 30, and a liquid (or steam) is added to the supply gas.
It constitutes a mechanism for mixing. Here, this liquid injection pipe 28 is connected to a liquid source (not shown) (or a steam source when 28 is a steam pipe).

In addition, in FIG. 1, the reference numeral 32 indicates a flow path for the solid-liquid mixture A formed in the casing 14, and the reference numeral 3
4 indicates a hanging wire for the aeration device 10.

Next, the operation of the embodiment shown in FIG. 1 will be explained.

When the impeller 20 is rotated by the electric motor M, the solid-liquid mixture A is sucked into the casing from the suction port 16 as shown by the arrow X in the figure, flows through the flow path 32, and then flows from the discharge port 18 as shown by the arrow Z It is discharged. At the same time, gas is supplied from a gas supply source (not shown) as indicated by arrow Y, and is blown out from the gas outlet 24 through the gas supply pipe 26 and the gas chamber 22 into the solid-liquid mixture flowing through the flow path 32. .

Here, a liquid injection pipe 28 is connected to the gas supply pipe 26, and a liquid (for example, fresh water) flows through this liquid injection pipe 28 as shown by the arrow W, so that the aeration device Inside the gas supply pipe 26 on the 10 side (downstream side), the supplied gas becomes a liquid mixed gas.
Then, the liquid mixture gas is blown out from the gas outlet 24 through the gas chamber 22, and if there is a stuck part on the wall surface of the flow path 32 near the gas outlet 24, the stuck part is moistened and the adhesion force is reduced. This prevents the gas outlet 24 from clogging. In addition, when the pipe 28 is a steam pipe, for example, water vapor flows inside it, and the confluence point 3
Moist gas will flow downstream of 0.

The amount of liquid contained in the liquid-mixed gas or the humidity of the humid air can be adjusted by measuring the amount of liquid or vapor using the flowmeter 36 and operating the valve 38 as appropriate. The amount of liquid or vapor is
Since the degree of adhesion to the wall surface near the gas outlet 24 varies depending on the characteristics (viscosity, solid-liquid ratio, temperature, etc.) of the solid-liquid mixture to be aerated, continuous or intermittent supply of the optimum amount can be performed.

The gas outlet 24 may be formed of, for example, slits that are continuously formed all around the circumference, slits that are formed intermittently at regular intervals, or slits that are formed continuously along the entire circumference, or slits that are formed intermittently at regular intervals. It is also constituted by a plurality of through holes formed at intervals. That is, the optimal shape of the gas outlet 24 may be selected depending on the object to be aerated.

The aeration apparatus of the present invention is not limited to the type shown in FIG. 1, but can be applied to various types. For example, the present invention can be applied to an aeration device of the type shown in FIG. 2, which sucks in a solid-liquid mixture from a suction port 52 at the bottom of a casing and discharges it from a discharge port 54 above. In other respects, the embodiment shown in FIG. 2 and the embodiment shown in FIG. 1 are substantially the same, and therefore their explanation will be omitted.

Further, in the illustrated embodiment, the liquid injection pipe (or steam pipe) is connected to the gas supply pipe, but the liquid injection pipe (or steam pipe) may be connected to the gas chamber.

[Effects of the Invention] As explained above, according to the aeration device of the present invention, even if a solid component adheres to the wall surface near the gas outlet, it is not dried by the supplied gas, and therefore the gas outlet No sessile substances will grow in the vicinity. Even if there are any adhered substances, they will be peeled off from the wall surface by the jet of liquid-mixed gas or moist air. Therefore, even if the system is operated for a long period of time, the gas outlet will not be blocked, and the desired aeration performance will be maintained.

In addition, any device that mixes and stirs gas in a solid-liquid mixture is not limited to the underwater mechanical device shown in the figure.
The present invention can also be applied to diffuser-type aeration devices (diffuser plates, diffuser pipes, perforated tubes, disc fusers, spargeers, etc.), pump circulation-type aeration devices, and the like. Furthermore, the present invention is applicable to sewage treatment equipment such as sewerage systems, used paper deinking equipment, oxidation equipment, floating equipment for floating objects in liquid, and all other equipment that mixes and stirs gas in solid-liquid mixtures in all industrial fields. It is possible.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional front view showing one embodiment of the present invention, and FIG. 2 is a partially sectional front view showing another embodiment. 10, 50... Aeration device, 12... Tank, 22... Gas chamber, 24... Gas outlet, 26... Gas supply pipe, 28
...Liquid injection pipe (or steam pipe), 32...Flow path for solid-liquid mixture, A...solid-liquid mixture.

Claims (1)

[Claims] 1. An aeration device that blows gas supplied from the outside into a solid-liquid mixture from a gas outlet, the aeration device comprising a mechanism for mixing liquid or vapor with the gas supplied from the outside.