JPH0642797Y2 - Floating aerator - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to an aerator (aeration device) for purifying sewage in a sewage treatment plant such as a factory wastewater treatment plant or an urban sewage treatment plant. The present invention relates to a floating aerator floating on the liquid surface.

[Conventional technology]

Conventionally, for treating sewage, liquid surface stirring type, air diffuser type,
A diffuser plate type is known, but recently, a technique using a mechanical drive device such as an aerator with an impeller to forcibly generate a gas-liquid circulation flow in the aeration tank to increase the aeration rate has been adopted. In particular, a floating aerator is used which is floated on the liquid surface by attaching a float to the aerator.

In an example of the floating aerator described above, as shown in FIG. 5, an impeller 3 is directly connected below the motor 2 supported by a float 1 so as to be immersed below the liquid surface. The casing 4 which reaches the vicinity of the bottom of the installation tank (aeration tank) so as to surround it is also supported by the float 1. The casing 4 is provided with an air suction portion 5 having a large number of small holes below the impeller 3, and the air suction portion 5 communicates with the outside air via an air supply pipe 6. In the figure, 7 is the bottom of the installation tank (pond).

During operation, the impeller 3 rotated by the motor 2 supplies the liquid (treatment liquid) into the casing 4 as indicated by arrow A.
It is sent from the upper side to the lower side, during which air is sucked from the supply pipe 6 to draw the gas-liquid mixed liquid as shown by the arrow B, and the bottom portion 7 of the installation tank
Aeration is performed by discharging along arrow C as indicated by arrow C. (See JP-A-58-6290) [Problems to be Solved by the Invention] Although the above-mentioned conventional example is effective in itself, the gas-liquid multiphase flow is circulated to the corner of the installation tank. In order to improve the aeration performance by doing so, a discharge flow velocity that is relatively high to some extent is required, and further, the discharge flow must be kept as slow as possible even after the discharge.

In order to deal with the above problems, a floating aerator as shown in FIG. 4 (a) is considered. This is a suction pipe connected to the bottom of the float 1.
The submersible motor 12 is mounted inside the impeller 13, and the impeller 13 is directly connected to the submersible motor 12 so that the submersible motor 12 is located below the water surface WL.
A deflector 15 having a discharge channel 14 formed between the float 1 and the upper surface of the float 1 is attached to the float 1. 16 in the figure is a bell mouth.

During operation, the impeller 13 is rotated by the submersible motor 12 to suck the liquid from the suction bell mouth 16 of the suction pipe 11 as shown by an arrow D, and passes through the discharge flow passage 14 formed on the upper portion of the float 1 to the atmosphere. As indicated by arrow E in the drawing, the liquid is radially scattered, the oxygen in the atmosphere is brought into contact with the liquid, and at the same time, when the discharge liquid falls and collides with the surface of the liquid in the installation tank, the oxygen is trapped. A surface aeration effect and a stirring effect can be obtained.

However, in the above-mentioned one, when the installation tank is shallow and the bell mouth 16 part of the suction pipe 11 is near the bottom 7 of the installation tank as shown in FIG. Although it can be sucked and scattered radially to the surface of the installation tank, when the installation tank is deep and the suction bell mouth 16 and the installation tank bottom 7 are separated as shown in FIG. 4 (b), the installation is performed. The liquid cannot be sucked from the deep part of the tank.

In such a case, if a conventional material is used, the float pipe should be increased in size by increasing the buoyancy by an amount corresponding to the weight of the float pipe other than the float portion increased by the extension of the suction pipe 11. There was a problem that it was unavoidable, and if the shape of the float part could not be changed, the suction pipe could not be extended according to the liquid depth of the installation tank (pond), Therefore, there is a problem in that it is impossible to suck up the liquid from the deep portion of the installation tank, and it is not possible to sufficiently aerate and stir the entire installation tank.

The present invention solves the above-mentioned problems, and allows the liquid to be sucked from the liquid deep inside the tank and be radially scattered to the liquid surface of the installed tank without enlarging the float portion regardless of the depth of the installed tank. It is intended to provide a floating aerator capable of

[Means for solving problems]

To achieve the above object, the present invention connects a suction pipe to a lower portion of a float, installs an impeller for sucking and discharging a liquid through the suction pipe at an upper portion of the suction pipe, and drives the impeller. In a floating aerator in which a motor is installed in a suction pipe or in an upper part of a float, and a deflector is installed above the float so as to form a discharge flow path between the float and the upper surface of the float, a float, an impeller, a suction pipe, etc. If the members other than the motor are close to the specific gravity of water, for example 1.0 ~
It is made of a material with a specific gravity in the range of 1.1 and is characterized in that the entire floating aerator including the weight of the motor can be floated on the liquid surface without increasing the size of the float.

As described above, the material having a specific gravity in the range of 1.0 to 1.1, which is close to the specific gravity of water, is composed of a special olefin-based material by reaction injection molding.

As described above, the suction pipe made of a light material having a specific gravity close to that of water can be extended by connecting and incorporating a plurality of suction pipes having a predetermined length according to the liquid depth in the installation tank.

[Action]

According to the present invention, as described above, the entire main body of the floating aerator except for the motor is close to the specific gravity of water, for example, the specific gravity.
It is made of a material in the range of 1.0 to 1.1, and the entire floating aerator including the weight of the motor can be floated on the liquid surface without increasing the size of the float. Even if the suction pipe is extended correspondingly,
Since the weight increase due to the extension is very small, even the same float can sufficiently cope with floating on the liquid surface in the installation tank. Therefore, since it is possible to extend the suction pipe to near the liquid bottom of the installation tank, it is possible to suck up the liquid in the deep part of the liquid and spread it radially to the liquid surface of the installation tank. The stirring can be sufficiently performed.

In this way, even if the liquid depth in the installation tank is deep, even if the suction pipe is connected, the total weight only slightly increases with respect to water, so it is not necessary to make the float large, and yet The liquid near the bottom of the installation tank can be sucked up and scattered on the surface of the liquid in the tank to aerate and stir the entire liquid in the installation tank.

〔Example〕

 Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a partial cross-sectional side view of a floating aerator showing an embodiment of the present invention, and FIG. 2 is a cross-sectional view of an essential part thereof, which are shown in FIGS. 4 (a) and 4 (b). The same reference numerals as the reference numerals indicate the same or equivalent portions.

In the figure, in the lower part of the float 1, for example, near the specific gravity of water made of a special olefin-based material, for example, 1.0
The suction pipe 21 made of a material having a specific gravity in the range of up to 1.1 is connected (connected) to two or more, and the suction bell mouth 22 attached to the suction pipe 21 at the bottom is connected to the suction pipe 21. The impeller 13 attached to the output shaft end is fixed to the motor support ring 23 and is provided between the float 1 and the suction pipe 21. Further, a deflector 15 is fixed to the upper portion of the float 1 so as to form the discharge flow path 14.

Next, Table 1 shows some examples of names and specific gravities of materials used in the present invention and conventionally used.

As shown in Table 1 above, the specific gravity of the special olefin system used in the present invention is very close to that of water as compared with other conventional materials.

In the figure, 24 is a submersible motor power cable.

Next, the operation will be described. As shown in the operation diagram of FIG. 3 in which two suction pipes 21 are connected, the underwater motor 12 is operated during operation.
By rotating the impeller 13 attached to the output shaft end of the, the liquid (treatment liquid) in the installation tank is sucked into the bell mouth 22
Is sucked in from the lower side as shown by the arrow, passes through the suction pipe 21, and is radially scattered into the atmosphere through the discharge flow path 14 formed by the float 1 and the deflector 15, and is aerated by entraining air. A stirring effect is obtained at the same time as the effect.

According to this embodiment, as described above, since the suction pipe 21 is made of a material having a specific gravity of 1.0 to 1.1, which is close to the specific gravity of water, which is made of, for example, a special olefin system, the float 1 has the same shape. The length of the suction pipe 21 connected to the lower part of the float can be freely set according to the liquid depth of the installation tank even if is used, and the water drainage position when the float 1 is floated is almost unchanged. The hydraulic performance of the impeller 13 does not change, the original performance of the floating aerator can be fully exerted, and stable aeration and stirring performance can be obtained.

Therefore, since the liquid in the installation tank (pond) can be sucked up and scattered radially on the surface of the liquid in the installation tank, the aeration and stirring effects are greatly improved. Moreover, since the weight of the main body and the parts are much lighter than the conventional ones, it can be installed manually at an optimum position in the installation tank without using mechanical equipment such as a crane.

In the above-described embodiment, the structure in which a plurality of suction pipes 21 are connected and incorporated has been described, but it is needless to say that the suction pipes can be used even when the suction pipe is single.

Further, the structure in which the motor for driving the impeller 13 is configured by the submersible motor 12 installed in the suction pipe 21 has been described, but the motor may be configured by a dry motor mounted on the float upper portion.

[Effect of device]

As described above, according to the present invention, the suction pipe is connected to the lower portion of the float, and the motor-driven impeller, which sucks and discharges the liquid through the suction pipe, is installed above the suction pipe. In a floating aerator equipped with a deflector that forms a discharge flow path between the float and the upper surface of the float, the members other than the motor part are made of a material close to the specific gravity of water. Since the entire floating aerator including the weight of the part can be floated on the liquid surface, even if the floats of the same shape are used, the suction pipe connected to the bottom of the float will be connected depending on the liquid depth of the installation tank. The length can be freely set, and since the position of water drifting when the float floats hardly changes,
The hydraulic performance of the impeller does not change, the original performance of the floating aerator can be fully exerted, and stable aeration and stirring performance can be obtained.

Therefore, since the liquid in the installation tank can be sucked up and scattered radially on the surface of the liquid in the installation tank, the aeration effect and the stirring effect are greatly improved. Moreover, since the weight of the main body and the parts are much lighter than the conventional ones, it can be manually installed at the optimum position in the installation tank without using mechanical equipment such as a crane.

In addition, the suction pipe connected to the lower part of the float has a structure in which a suction pipe having a length corresponding to the liquid depth in the tank can be connected between the float and the suction bell mouth, so that the installation tank The liquid near the bottom of the (pond) can be scattered radially around the liquid surface. Therefore, since it is possible to sufficiently stir the liquid on the liquid surface of the tank and the liquid in the deep portion where the dissolved oxygen is lower and the liquid temperature is different compared to the vicinity of the liquid surface, Aeration and stirring effects are greatly improved.

Further, by constructing the members other than the motor part with the special olefin-based material by the reaction-type injection molding method, a very light material having a specific gravity of 1.0 to 1.1 close to that of water can be obtained.

[Brief description of drawings]

FIG. 1 is a partial sectional side view of a floating aerator showing an embodiment of the present invention, and FIG. 2 is a sectional view of an essential part of FIG.
FIG. 3 is an explanatory view showing an operating state of the present invention, and FIG. 4 (a).
(B) is an explanatory view showing different usage states of an aerator of the type which is the basis of the present invention, and FIG. 5 is an explanatory view of a floating aerator showing a conventional example. 1 ... Float, 12 ... Submersible motor, 13 ... Impeller, 14 ... Discharge passage, 15 ... Deflector, 21 ... Suction tube, 22 ... Suction bell mouth, 23 ... Motor support ring.

Claims (4)

[Scope of utility model registration request] 1. A suction pipe is connected to a lower portion of a float, and a motor-driven impeller that sucks and discharges liquid through the suction pipe is installed above the suction pipe. Above the float, an upper surface of the float is provided. In the floating aerator in which the deflector is attached so as to form the discharge flow path between, the members other than the motor unit such as the float, the impeller and the suction pipe are
A floating aerator characterized by being made of a material having a specific gravity close to that of water so that the entire floating aerator including the weight of the motor can be floated on the liquid surface without increasing the size of the float. 2. A floating aerator according to claim 1, wherein a motor for driving the impeller is mounted inside the suction pipe or above the float. 3. A floating aerator according to claim 1, wherein members other than the motor portion such as the float, the impeller and the suction pipe are made of a special olefin-based material produced by a reaction injection molding method. 4. A suction pipe is connected to a lower portion of the float, and a motor-driven impeller, which sucks and discharges liquid through the suction pipe, is installed on the upper portion of the suction pipe, above the float, and on the upper surface of the float. In the floating aerator in which the deflector is attached so as to form the discharge flow path between, the members other than the motor unit such as the float, the impeller and the suction pipe are
The suction pipe is made of a material with a specific gravity close to that of water, and the floating aerator including the weight of the motor can be floated on the liquid surface without increasing the size of the float. The floating aerator is characterized in that a plurality of suction pipes of a predetermined length can be connected and extended according to the liquid depth in the installation tank.