JP2003144881A - Gas-liquid mixing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas-liquid mixing apparatus which can inject air into, for example, the sewage pressure-feeding pipeline of an air injection type sewage pressure-feeding system while reducing running cost. SOLUTION: The primary side 4A outlet of the sewage pressure-feeding pipeline 4 is connected to the one end side in the direction of the axis line C of a gas-liquid mixing rotation tank 14 by making to have a tangential direction or a direction near a tangent line, and the secondary side 4B inlet of the pipeline 4 is connected to the other end part side. An air suction pipe 15 provided with a plurality of air discharge ports 15A is airtightly inserted into the axial center part of the tank 14, and the outside edge opening part 15C of the pipe 15 is opened to air. A direct advance flow of sewage introduced into the tank 14 is converted into a circular flow S along the inner surface of the peripheral wall 14C of the tank 14, and is discharged to the secondary side 4B. Thereby, a negative pressure part is formed at the outer peripheral part of an air suction pipe 15, the air is injected into the tank 14 by using a pressure difference between atmospheric pressure and the negative pressure part, and the air is mixed with the sewage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas-liquid mixing device for mixing air into a liquid stream, and more particularly to a gas-liquid mixing device suitable for an air injection type sewage pumping system.

[0002]

2. Description of the Related Art Conventionally, a sewage pumping system shown in FIG. 4 has been known. This system is provided with a sewage pump 3 for pumping sewage 2 in a pump well 1 and a sewage pumping line 4.

However, according to the sewage pumping system having the above structure, when sewage stays in the sewage pumping line 4 for a long time, the inside of the pipe becomes anaerobic and sulfides are generated, and a bad odor is generated and the sewage pumping line 4 is generated. Cause corrosion.

[0004] Such an offensive odor and sewage pressure feeding pipeline 4
As a sewage pumping system that suppresses the formation of sulfides that cause corrosion of water, for example, an air injection type sewage pumping system shown in FIG. 5 is provided. This system is provided with a sewage pump 3 for pumping sewage 2 in a pump well 1, a sewage pumping line 4, and an air injection system 5, and has a sewage pumping line 4
Is connected to the discharge port of the sewage pump 3 through a check valve 6 and a flow meter 7 connected in series on the upstream side thereof. The air injection system 5 includes an air compressor 8, a pressure accumulator tank 9, and a pressure reducing valve. An air injection pipe 5A in which an air compressor 8 is connected to the sewage pressure feed pipe line 4 is provided with 10, a flow meter 11, a flow rate adjusting valve 12, a check valve 12A, and the like interposed in series.

According to the air-injection type sewage pumping system having the above-mentioned structure, by injecting air into the sewage pumping line 4 by the air injection system 5 to aerate the pipe, the inside of the pipe is aerobicized to generate sulfide. It is possible to suppress the generation of a bad odor and the corrosion of the sewage pressure-feeding pipeline 4 by suppressing.

[0006]

However, in this conventional air-injection type sewage pumping system, since it is necessary to introduce high-pressure air from the air injection system 5 into the sewage pumping line 4, normally, an air compressor is used. In the high-power continuous operation of No. 8, air is injected into the wastewater pressure-feeding pipeline 4. For this reason,
The air compressor 8 consumes a large amount of power and has a drawback of increasing running costs.

The present invention has been made in view of the above circumstances, and it is possible to reduce the running cost and inject air into, for example, the sewage pumping line of the air injection type sewage pumping system. An object is to provide a liquid mixing device.

[0008]

In order to achieve the above object, the gas-liquid mixing device according to the invention of claim 1 is a gas-liquid mixing device in which air is mixed with the liquid pumped in the liquid pumping line. In the device, a cylindrical gas-liquid mixing swirl for converting a straight flow of the liquid introduced from the primary side of the liquid pressure feeding pipeline into a swirling flow along the inner surface of the peripheral wall and discharging the swirling flow to the secondary side of the liquid pressure feeding pipeline. A tank and air which extends in the axial direction of the gas-liquid mixing swirl tank and is inserted into the axial center of the gas-liquid mixing swirl tank, and whose outer end opening is open to the atmosphere outside the gas-liquid mixing swirl tank. The air suction pipe is provided with a plurality of air discharge ports on the wall of the air suction pipe.

Further, as in the second aspect of the invention, an air injection system may be connected to the air suction pipe.

According to the first aspect of the invention, the straight flow of the liquid introduced into the gas-liquid mixing swirl tank from the primary side of the liquid pressure-feeding conduit becomes a swirl flow along the inner surface of the wall of the gas-liquid mixing swirl tank. By converting and discharging the liquid to the secondary side of the liquid pressure feeding conduit, a negative pressure portion is formed in the vicinity of the axial center of the gas-liquid mixing swirl tank and its outer periphery. Since the air suction pipe is inserted into the axial center of the gas-liquid mixing swirl tank, the negative pressure portion has a plurality of air discharge ports provided on the pipe wall of the air suction pipe and an outer end opening of the air suction pipe. Through the atmosphere. Therefore, due to the pressure difference between the atmospheric pressure and the negative pressure portion, air is sucked into the gas-liquid mixing swirl tank through the air suction pipe, the gas-liquid is mixed in the gas-liquid mixing swirl tank, and the air is sucked to the secondary side of the liquid pressure feeding pipeline. It can be discharged as a liquid mixed fluid.

By connecting the air injection system to the air suction pipe, the air injection capacity of the air injection system can be suppressed low.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing a first embodiment of the present invention. The same or corresponding parts as those of the conventional example described with reference to FIGS. 4 and 5 are designated by the same reference numerals, and the description of the overlapping structure and the description of the operation will be omitted.

In FIGS. 1 and 2, a gas-liquid mixing device 1
3 includes a gas-liquid mixing swirl tank 14 and an air suction pipe 15. The gas-liquid mixing swirl tank 14 has a cylindrical shape in which both end portions in the axis C direction are airtightly closed by the closing plates 14A and 14B, and the peripheral wall portion 14C is provided near the closing plate 14A on the one end side in the axis C direction. It has a tangential direction or a direction close to the tangential line, connects the outlet of the primary side 4A in the wastewater pressure-feeding pipeline 4, and near the closing plate 14B on the other end side in the axial line C direction of the peripheral wall portion 14C, in the tangential direction or Secondary side 4B in the sewage pumping pipeline 4 having a direction close to the tangent line
The entrance of is connected. In addition, the upstream end of the primary side 4A in the sewage pumping pipeline 4 is connected to the discharge port of the sewage pump 3 as shown in FIG. 5, and the suction port of the sewage pump 3 is a pump well that stores the sewage 2. Connected to 2.

On the other hand, the air suction pipe 15 is provided with a plurality of air discharge ports 15A, 15A ... Penetrating the pipe wall, and the inner end portion in the direction of the axis C is airtightly closed by a closing plate 15B. There is. The air suction pipe 15 penetrates the closing plate 14A of the liquid mixing swirl tank 14 in an airtight manner and is inserted into the axial center part of the gas liquid mixing swirl tank 14, and the outer end opening 15C is provided in the gas liquid mixing swirl tank 14. A check valve 16 that is open to the outside of the air and that allows the intake flow of air indicated by the arrow A and blocks the flow in the direction opposite to the arrow A is provided directly downstream of the outer end opening 15B. Has been done.

With such a structure, the sewage pumping line 4
The straight flow of the sewage 2 introduced into the gas-liquid mixing swirl tank 14 from the primary side 4A is the peripheral wall 14C in the gas-liquid mixing swirl tank 14.
Is converted into a swirling flow S along the inner surface of the liquid and is discharged to the secondary side 4B of the liquid pressure-feeding conduit 4. In this way, the sewage swirls along the inner surface of the peripheral wall 14C, so that the pressure near the axial center of the gas-liquid mixing swirl tank 14 and its outer periphery, that is, the air suction pipe inserted into the gas-liquid mixing swirl tank 14 The pressure of the outer peripheral part of 15 becomes lower than the pressure of the peripheral wall 14C side of the gas-liquid mixing swirl tank 14, and a negative pressure part is formed in the outer peripheral part of the air suction pipe 15.

Since the air suction pipe 15 is inserted into the axial center of the gas-liquid mixing swirl tank 14, the negative pressure portion has a plurality of air discharge ports 15A, 15A provided on the wall of the air suction pipe 15.
... and the outer end opening 1 of the check valve 16 and the air suction pipe 15.
It communicates with the atmosphere through 5C. Therefore, air is sucked into the air suction pipe 15 due to the pressure difference between the atmospheric pressure and the negative pressure portion, and the air is discharged from the plurality of air discharge ports 15A, 15A ... It can be discharged to the secondary side 4B of the sewage pressure-feeding pipeline 4 as a gas-liquid mixed fluid in which sewage and

As described above, since the air can be injected into the gas-liquid mixing swirl tank 14 by utilizing the pressure difference between the atmospheric pressure and the negative pressure portion, it is required in the conventional air injection type sewage pumping system. The air injection system 5 that has been used is no longer necessary. Therefore, not only the equipment cost can be reduced, but also the running cost can be reduced.

On the other hand, as shown in FIG.
The air injection pipe 5A of the air injection system 5 may be connected to the outer end opening 15C of the. In FIG. 3, the same or corresponding parts as those of the embodiment described with reference to FIGS. 1 and 2 and the conventional example described with reference to FIG. In this way, by connecting the air injection pipe 5A of the air injection system 5 to the outer end opening 15C of the air intake pipe 15, the above-mentioned negative pressure portion formed from the air injection system 5 to the outer peripheral portion of the air intake pipe 15 is connected. Since air is injected into the air, the air injection capacity of the air injection system 5 can be suppressed to a low level. That is, since the air can be easily injected even if the injection air pressure of the air injection system 5 is kept low, the power consumption of the air compressor 8 can be reduced and the running cost can be reduced.

In the above embodiment, the gas-liquid mixing device 13 according to the present invention is applied to an air injection type sewage pumping system for injecting air into the sewage in the sewage pumping line 4. The application of the gas-liquid mixing device 13 is not limited to the above-described embodiment, but can be applied to other air-injection liquid pressure-feeding systems that mix air with the liquid flowing in the pipeline.

[0020]

As described above, since the gas-liquid mixing device of the present invention is constructed, the following special effects are obtained.

According to the first aspect of the invention, the straight flow of the liquid introduced into the gas-liquid mixing swirl tank is converted into a swirl flow along the inner surface of the wall of the gas-liquid mixing swirl tank, and the gas-liquid mixing swirl tank A negative pressure portion is formed near the shaft center portion and its outer periphery, and the negative pressure portion communicates with the atmosphere through a plurality of air discharge ports provided on the wall of the air suction pipe and an outer end opening of the air suction pipe. By doing so, air can be injected by utilizing the pressure difference between the atmospheric pressure and the negative pressure portion to mix the gas and liquid, so that the air injection system is not required. Therefore, the running cost can be reduced.

According to the second aspect of the invention, by connecting the air injection system to the air intake pipe, the air is injected from the air injection system to the negative pressure portion formed on the outer peripheral portion of the air intake pipe. Therefore, even if the air injection capacity of the air injection system is suppressed to a low level, the air can be easily injected, so that the running cost can be reduced.

[Brief description of drawings]

FIG. 1 is a side view showing a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line BB of FIG.

FIG. 3 is a view corresponding to FIG. 2 showing a second embodiment of the present invention.

FIG. 4 is a configuration diagram of a conventional sewage pumping system.

FIG. 5 is a configuration diagram of a conventional air-injection type sewage pumping system.

[Explanation of symbols]

2 sewage 4 sewage pressure feed pipe line (liquid pressure feed pipe line) 4A primary side 4B secondary side 5 air injection system 13 gas-liquid mixing device 14 gas-liquid mixing swirl tank 14C gas-liquid mixing swirl tank peripheral wall (gas-liquid mixing swirl tank 15) Air suction pipe 15A Air discharge port 15C Outer end opening C of air suction pipe C Axis S Swirling flow

Claims (2)

[Claims] 1. A gas-liquid mixing device for mixing air with a liquid to be pressure-fed in a liquid pressure-feeding conduit, wherein a straight flow of the liquid introduced from the primary side of the liquid pressure-feeding conduit is swirling along an inner surface of a peripheral wall. And a cylindrical gas-liquid mixing swirl tank which is converted into and is discharged to the secondary side of the liquid pressure-feeding pipeline, and extends in the axial direction of the gas-liquid mixing swirl tank and is inserted into the axial center portion of the gas-liquid mixing swirl tank. And an air intake pipe having an outer end opening opened to the atmosphere outside the gas-liquid mixing swirl tank, and a plurality of air discharge ports are provided on the wall of the air intake pipe. Characteristic gas-liquid mixing device. 2. The gas-liquid mixing device according to claim 1, wherein an air injection system is connected to the air suction pipe.