JP2001321647A - Air permeating agitation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air permeating agitation device which is used for a flue gas desulfurizing apparatus, or the like, is excellent in dispersion of gas to an agitating liquid and high in gas absorbing efficiency and in which the accumulation of air bubbles is not generated on an agitation blade. SOLUTION: The boss part of the agitation blade 2 is formed into a cylindrical tube boss 4, which is fixed on a driving shaft 6 while interposing a supporting plate 5 to form a gap between the boss 4 and the shaft 6. A discharging port 7a of an air permeating tube 7 is formed to have such a structure that the shaft 6 can be inserted and is made open to the inside of the boss 4. An outflow port 4c of the boss 4 is made open to the downstream side of the blade 2 while keeping a sufficient distance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a flue gas desulfurization apparatus and the like, in which a gas such as a combustion exhaust gas is introduced into a stirring tank provided with stirring blades to stir the liquid in the stirring tank. The present invention relates to a stirring device for use.

[0002]

2. Description of the Related Art As a flue gas desulfurization system, there is a system in which sulfur dioxide contained in exhaust gas is absorbed by an absorbent in a liquid and removed as gypsum or the like.

That is, a liquid containing slurry or the like is put into a stirring tank, and a gas such as a flue gas is introduced into the stirring tank to stir the liquid. The stirring apparatus is as shown in FIG. , A stirring blade b from the side in a stirring tank a containing liquid.
Conventionally, a structure in which a discharge port c of a ventilation pipe connected to a gas is disposed on the negative pressure side of the stirring blade is provided.

However, in this structure, a bubble reservoir (cavity) as shown in FIG.
The flow pattern of the liquid in the vessel changes and the stirring tank a
There is a problem that the dispersion of the gas in the inside becomes poor and the gas absorption efficiency decreases.

For this reason, as shown in FIG. 7, there is known a stirrer in which a discharge port c of a ventilation pipe is arranged on the pressure side (discharge side) of a stirring blade b so as to eliminate a bubble pool entangled with the blade. I have.

The arrow X indicates the direction of the discharge flow of the stirring blade b.

[0007]

However, a method of arranging a gas outlet c on the pressure side of the stirring blade b (FIG. 7).
Since gas dispersion in the liquid is performed only by the discharge flow from the stirring blade b, good gas dispersion cannot be obtained, and the entire flow pattern changes under the influence of the ventilation, so that the gas absorption There was a problem that was inefficient.

An object of the present invention is to solve these problems and to provide a stirrer for aeration and stirring that can obtain good gas dispersion and high gas absorption efficiency.

[0009]

According to the present invention, in order to achieve the above object, a boss portion of a stirring blade is formed in a cylindrical tube boss, and the tube boss is provided at a distal end portion of a drive shaft on an outer peripheral surface thereof. The tube boss has a tip opening formed at a gas outlet.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a stirring apparatus for aeration and stirring according to the present invention will be described with reference to FIGS.

FIG. 1 is a longitudinal sectional view of a stirring apparatus 1 according to the first embodiment. A driving pipe 6 of a stirring blade 2 is provided with a ventilation pipe projecting from the side of the stirring tank 3 toward the inside. 7 is formed so as to pass through the center.

Reference numeral 7a denotes a gas chamber provided outside the stirring vessel 2 and communicates with the ventilation pipe 7, 7b designates a gas introduction pipe communicating with the gas chamber 7a, and 7c designates a gas chamber 7b provided on the side wall of the stirring vessel 2 in the gas chamber 7b. A flange forming opposing side surfaces is shown, and the drive shaft 6 is rotatably fitted to the flange 7c.

The stirring blade 2 is a high discharge type axial flow blade.

That is, as shown in FIGS. 2 and 3, the stirring blade 2 has a plurality of propeller blades 2a fixed radially on the outer periphery of a cylindrical tube boss 4, and has an inner periphery of the tube boss 4. A plurality of support plates 5 are provided so as to project radially inward, and the stirring blade 2 is axially fixed to a drive shaft 6 via these support plates 5.

The tube boss 4 forms a divergent nozzle-like portion 4a by increasing the diameter of one end of the cylindrical body toward the root, and further forms a discharge port 7d of a ventilation pipe 7 inside the tube boss 4. And the ventilation pipe 7 and the tube boss 4 partially form a double cylindrical pipe structure 4b.

The tube boss 4 has an outlet 4c at the distal end thereof protruding to a position sufficiently distant on the downstream side of the propeller blades 2a at the outer periphery.

The length of the double cylindrical tube structure 4b can be adjusted by moving the stirring blade 2 back and forth.

The support plate 5 has a flat plate shape and is formed so as to act as a rectifying blade for dispersing and miniaturizing the gas passing between the support plates 5.

The vent pipe 7 is a conduit for introducing a gas such as exhaust gas into the stirring tank 3, and the drive shaft 6 passes through the center of the discharge port 7 d at the tip of the vent pipe 7.

Next, the operation and effect of the stirring device 1 of the present embodiment will be described.

When flue gas desulfurization is performed using the stirrer 1, a gas containing sulfur dioxide is passed through the stirrer 1 through the ventilation pipe 7.
To supply.

The stirring tank 3 stores a liquid 8 suspended in a slurry state using, for example, calcium hydroxide, calcium carbonate or the like as an absorbent. A flow in the direction of X is created and agitated.

On the other hand, the gas from the ventilation pipe 7 is discharged into the tube boss 4 from the discharge port 7d as shown by the arrow A in FIG. 2, and the divergent portion of the tube boss 4 is formed by the ejector effect of the double cylindrical pipe structure 4b. The liquid is sucked from the nozzle portion 4a in the direction of arrow B, and passes through the support plate 5 while mixing with the liquid. At this time, the support plate 5 acts as a rectifying blade,
Dispersion and miniaturization of gas mixed with liquid are promoted.

The gas mixed with the liquid to form bubbles is sent from the outlet 4c of the tube boss 4 to the discharge side of the stirring blade 2 in the stirring tank 3, and the high discharge type propeller blade 2a
A good flow pattern is obtained by riding on the circulating flow in the tank created by the method, so that the air bubbles can be made finer and the dispersion efficiency can be improved, and the fluidity of the slurry in the liquid and the solid such as the formed gypsum can be improved. That is, the flow of the liquid in the tank is enhanced by the synergistic effect of the discharge flow of the blade and the discharge energy of the gas. The outlet 4c of the tube boss 4 is connected to the propeller blade 2
Since the projection is made at a position sufficiently distant from “a”, entanglement of air bubbles with the wing is prevented. Thus, the present stirring device 1 can obtain high gas absorption efficiency.

The length of the double cylindrical pipe structure 4b formed by the ventilation pipe 7 and the tube boss 4 can be adjusted so that the ejector effect is optimized.

In the present embodiment, the stirring blade 2 is an axial flow blade, but this may be an oblique flow blade.

A second embodiment of the agitating apparatus for aeration and agitation of the present invention will be described with reference to FIG.

The stirring device 11 of the present embodiment also has a stirring blade 12 formed at the tip of a drive shaft 16 that passes through a gas ventilation pipe 17.

That is, the stirring blade 12 includes a plurality of propeller blades 12.
The tube boss 14 provided with a is fixed to the outer periphery of the distal end of the drive shaft 16 via a plurality of support plates 15.

The tube boss 14 has a cylindrical shape and is formed to have substantially the same diameter as the ventilation pipe 17, and the rear end face 14 a of the tube boss 14 and the front end face 17 a of the ventilation pipe 17 have a predetermined space. Are arranged so as to face each other or to be in sliding contact with each other in a freely rotatable manner.

At the tip of the tube boss 14, a plurality of ejection pipes 14b are provided to project obliquely outward in the axial direction.

Each of the jet pipes 14b is formed to have a tapered shape, and the tip of the jet pipe 14b is bent in an axial direction parallel to the drive shaft 16 so as to be spaced from each other on the downstream side of the propeller blade 12a. It is open.

Further, there is a cylindrical cover 17b which covers the outer peripheral portion of the front end face 17a of the ventilation pipe 17 and the outer peripheral portion of the rear end face 14a of the tube boss 14. Liquid from inside is inside the tube boss 14. Prevents intrusion. The arrow X indicates the direction of the discharge flow of the stirring blade 12.

Next, the operation and effects of the stirring device 11 of the present embodiment will be described.

The gas sent from the gas introduction pipe 17c is sent into the rotating tube boss 14 through the ventilation pipe 17, and is ejected from a plurality of ejection pipes 14b into the liquid in the stirring layer 13.

The jet pipes 14b are provided at a sufficient distance from the propeller blades 12a forming the stirring blades 12, so that air bubbles are not entangled with the impellers, and a plurality of jet pipes 14b are provided. As a result, the gas is discharged over a wide area in the stirring tank 13, so that the mixing and diffusion of the liquid and the gas in the tank are convenient, and the gas absorption efficiency is improved.

A third embodiment of the agitating device for aeration and agitation of the present invention will be described with reference to FIG.

In the stirring device 21 of the present embodiment, a tube boss 24 having a plurality of propeller blades 22a is fixed to the outer periphery of the tip end of a drive shaft 26 via a plurality of support plates 25, and the stirring blade 22 is At the same time, the drive shaft 26 was formed in a hollow cylindrical shape, and a gas passage 26a was provided therein.

The drive shaft 26 has a discharge port 26 b at the end thereof opened into the tube boss 24.

The tube boss 24 is formed in a funnel shape with the diameter of the rear end portion 24a being large, and the outlet port 24b at the front end portion is protruded to a position sufficiently distant on the wake side of the mounting position of the propeller blade 22a. I let it.

The drive shaft 26 is provided with an introduction hole 26c for introducing gas from the gas introduction pipe 27b into the gas passage 26a in the drive shaft 26 in the gas chamber 27a.

Next, the operation and effects of the stirring device 21 of the present embodiment will be described.

The gas sent from the gas inlet 27b is introduced into the gas passage 26a in the drive shaft 26 through the inlet 26c, and is discharged from the outlet 26b into the tube boss 24.

The tube boss 24 sucks liquid from the funnel-shaped rear end 24a by the ejector effect of the gas discharged from the discharge port 26b, and discharges a mixture of these liquid and gas bubbles from the outlet 24b at the front end. Stirring tank 2
Release into 3.

The outlet 24b is connected to the propeller blade 22
a, the air bubbles are not entangled with the blades, and a good flow pattern can be obtained by riding on the circulation flow in the tank formed by the propeller blades 22a. A good stirring device for aeration and stirring can be obtained.

The support plate 5 in the first embodiment, the support plate 15 in the second embodiment, and the support plate 25 in the third embodiment are formed so as to operate as rectifying blades. However, they may be formed to operate as buckets for axial pumps.

The roots of the propeller blades 2a, 12a, 22a are fixed through the tube bosses 4, 14, 24, and the ends of the roots are fixed to the outer peripheral surfaces of the drive shafts 6, 16, 26. 15 and 25 may be formed.

[0048]

As described above, according to the present invention, the gas is sent out to the discharge side of the stirring blade through the tube boss at the center of the stirring blade, so that no air bubbles are entangled with the blade and the gas in the liquid This has the effect of obtaining a good gas dispersion in the gas and providing a stirrer for aeration and stirring with high gas absorption efficiency.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a stirring device according to a first embodiment.

FIG. 2 is a partial vertical sectional view of the stirring device.

FIG. 3 is a sectional view taken along line III-III in FIG. 2;

FIG. 4 is a longitudinal sectional view of a stirring device according to a second embodiment.

FIG. 5 is a longitudinal sectional view of a stirring device according to a third embodiment.

FIG. 6 is an explanatory view of an example of a conventional stirring device for aeration and stirring.

FIG. 7 is an explanatory view of another example of a conventional stirring device for aeration and stirring.

[Explanation of symbols]

 1, 11, 21 Stirring device 2, 12, 22 Stirring blade 3, 13, 23 Stirring tank 4, 14, 24 Tube boss 4c, 24b Outlet 5, 15, 25 Support plate (rectifying blade) 6, 16, 26 Drive Axis 7, 17 Vent pipe 14b Spout pipe

Claims (9)

[Claims] 1. A boss portion of a stirring blade is formed in a cylindrical tube boss, and the tube boss is fixed to a distal end portion of a drive shaft with a gap on an outer peripheral surface thereof. A stirrer for aeration and stirring, which is formed at the outflow port. 2. A ventilation stirrer according to claim 1, wherein a gas vent pipe is provided in which the drive shaft is inserted inward, and a distal end opening of the vent pipe faces the tube boss. Stirrer. 3. The agitating apparatus for aeration and agitation according to claim 2, wherein the ventilation pipe and the tube boss partially form a double cylindrical pipe structure. 4. A gas vent pipe having the drive shaft inserted inward is provided, and a front end face of the gas pipe and a rear end face of the tube boss are opposed to each other, and a plurality of ejection pipes are provided at the front end of the tube boss. The stirrer for ventilation stirring according to claim 1, wherein the jet pipe extends obliquely outward so that its tip opening faces the flow direction formed by the stirring blades. . 5. The apparatus according to claim 1, wherein the drive shaft is formed in a hollow cylindrical shape, the inside of the drive shaft is formed as a gas passage, and a distal end opening of the gas passage faces the inside of the tube boss. The stirring device for aeration stirring according to the above. 6. The agitating apparatus for aeration and agitation according to claim 2, wherein the tube boss is formed in a shape of a divergent nozzle with a diameter increasing toward the root. 7. A rectifying vane for dispersing and miniaturizing a gas passing between said support plates, said support plate fixing said tube boss to said drive shaft. The stirrer for aeration stirring according to any one of the above. 8. The agitating device for aeration and agitation according to claim 3, wherein the length of the double cylindrical tube structure is adjustable. 9. The agitating device for aeration and agitation according to claim 1, wherein the stirring blade is a high discharge type axial flow blade.