CN216825452U

CN216825452U - External circulation flue gas dust removal and desulfurization device

Info

Publication number: CN216825452U
Application number: CN202220395873.7U
Authority: CN
Inventors: 赵勇; 孙跃宗; 曹立强; 宋永亮; 孙跃荣
Original assignee: Shenzhou Jiaxin Chemical Co ltd
Current assignee: Shenzhou Jiaxin Chemical Co ltd
Priority date: 2022-02-25
Filing date: 2022-02-25
Publication date: 2022-06-28
Anticipated expiration: 2032-02-25

Abstract

The utility model discloses an external circulation flue gas dust removal and desulfurization device, which comprises an outer cylinder, a middle cylinder, an inner cylinder and an external circulation system, wherein the middle cylinder is positioned between the outer cylinder and the inner cylinder, so that an outer cavity, a middle cavity and an inner cavity are formed in sequence from outside to inside; a first air inlet is formed in the bottom of the outer cylinder body; a second air inlet is formed in the top of the middle cylinder body; a third air inlet is formed in the bottom of the inner cylinder; the external circulation system comprises an external circulation tank. This is novel through outer circulation system improved the utilization ratio of sodium hydroxide solution/sodium carbonate solution, and desulfurization effect is good.

Description

External circulation flue gas dust removal and desulfurization device

Technical Field

The utility model relates to a chemical industry equipment, more specifically relate to an extrinsic cycle flue gas dust removal desulphurization unit.

Background

In the production of barium sulfate, barium carbonate, strontium carbonate and the like, a converter kiln is usually adopted for crude barium production, dust removal and desulfurization treatment are required for tail gas of the converter kiln, bag type dust removal, electric dust removal and the like are generally adopted for dust removal, dry desulfurization or wet desulfurization can be adopted for desulfurization, and wet desulfurization equipment generally adopts a mode of connecting a plurality of absorption towers in series to form a large floor area and large investment due to good effect and low cost of wet desulfurization which is widely adopted at present.

CN206262344U and CN201105203Y both disclose a flue gas desulfurization device, which have similar structures, and take CN206262344U as an example, it is provided with an outer cylinder and an inner cylinder, an air inlet is arranged on the upper part of the outer cylinder, a spray nozzle is arranged on the top of the outer cylinder, the spray nozzle sprays a sodium hydroxide solution downwards, the sprayed solution forms a desulfurization solution at the funnel-shaped bottom, the flue gas enters the inner cylinder through the desulfurization solution and then is discharged, the desulfurization solution at the bottom is maintained in an alkaline environment, and when the desulfurization solution reaches a certain amount, the flue gas is discharged through a liquid discharge port. The desulfurizing device with the structure has the advantages that on one hand, the flowing direction of flue gas is the same as that of the sodium hydroxide solution sprayed by the nozzle, the solution utilization rate is low, the desulfurizing effect is poor, on the other hand, the absorbed solution is discharged in the form of waste liquid, and the discharged waste liquid can pollute the surrounding environment.

SUMMERY OF THE UTILITY MODEL

Aiming at the defects of the prior art, the utility model provides an external circulation flue gas dust removal and desulfurization device.

An external circulation flue gas dust removal and desulfurization device comprises an outer cylinder, a middle cylinder, an inner cylinder and an external circulation system, wherein the middle cylinder is positioned between the outer cylinder and the inner cylinder, so that an outer cavity, a middle cavity and an inner cavity are sequentially formed from outside to inside; the bottom of the outer cylinder is provided with a first air inlet which is communicated with the outer cavity, the top of the outer cavity is provided with an outer cavity spray head, the outer cavity spray head is connected with a first absorption liquid annular pipeline, the bottom of the outer cavity is provided with a first liquid collecting tank, and the bottom of the first liquid collecting tank is connected with a recovery pipe; a second air inlet is formed in the top of the middle cylinder, the outer cavity is communicated with the middle cavity through the second air inlet, a middle cavity spray head is arranged at the top of the middle cavity, and the middle cavity spray head is connected with a second absorption liquid annular pipeline; a third air inlet is formed in the bottom of the inner cylinder body, the middle cavity is communicated with the inner cavity through the third air inlet, and an annular grid is arranged at the third air inlet; the external circulation system comprises an external circulation tank, the external circulation tank is connected with the recovery pipe, and the external circulation tank is further connected with the first absorption liquid annular pipeline through an external circulation pipe.

This neotype beneficial effect is: this novel absorption tower that uses has solved the task that the series connection absorption tower bore for the input reduces, and desulfurization effect is good, and this neotype device still has fine wet dedusting's effect simultaneously concurrently. The utilization rate of the sodium hydroxide solution/sodium carbonate solution is improved through the external circulation system, and the PH value of the first absorption liquid is easy to adjust.

Drawings

FIG. 1 is a schematic structural diagram of an external circulation flue gas dust removal and desulfurization device;

FIG. 2 is a top view of the external circulation flue gas dust removal and desulfurization device.

Detailed Description

The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments of the present invention when taken in conjunction with the accompanying drawings. Like reference numerals refer to like parts throughout the drawings. The drawings are not intended to be to scale, emphasis instead being placed upon illustrating the principles of the invention.

Referring to fig. 1 and 2, the flue gas dust removal and desulfurization device comprises an outer cylinder 2, a middle cylinder 3 and an inner cylinder 4, wherein the middle cylinder 3 is positioned between the outer cylinder 2 and the inner cylinder 4, so that an outer cavity, a middle cavity and an inner cavity are sequentially formed from outside to inside, a first air inlet 1 is arranged at the bottom of the outer cylinder 2 and communicated with the outer cavity, an outer cavity spray head 5 is arranged at the top of the outer cavity, and the outer cavity spray head 5 is connected with a first absorption liquid annular pipeline 6; the top of the middle cylinder body 3 is provided with a second air inlet 7, the outer cavity is communicated with the middle cavity through the second air inlet 7, the top of the middle cavity is provided with a middle cavity spray head, and the middle cavity spray head is connected with a second absorption liquid annular pipeline 12; the bottom of the inner cylinder body 4 is provided with a third air inlet, the middle cavity is communicated with the inner cavity through the third air inlet, and the third air inlet is provided with an annular grid 13.

A first liquid collecting groove 14 is formed in the bottom of the outer cavity, and a recovery pipe 15 is connected to the bottom of the first liquid collecting groove 14; a second liquid collecting groove 16 is arranged at the bottom of the inner cavity, and a liquid discharge pipe 17 is connected to the bottom of the second liquid collecting groove 16. The liquid discharge pipe 17 extends to the outside of the desulfurization device and is connected with an inverted U-shaped pipeline 20, a drain pipeline 19 is arranged at the bottom of the inverted U-shaped pipeline 20, and a liquid discharge control valve 18 is arranged on the drain pipeline 19.

Further, a W-shaped demister 11 is arranged at the upper part of the inner cavity, the W-shaped demister 11 can be provided with multiple layers, for example, two layers, a washer 10 is arranged on the W-shaped demister 11, a flue gas outlet 8 is arranged at the top of the inner cavity, and an inspection hole 9 is arranged on the inner cylinder 4.

The novel three-sleeve type absorption dust removal device comprises an outer cylinder body 2, a middle cylinder body 3 and an inner cylinder body 4, wherein a first air inlet 1 is formed in the lower portion of the outer cylinder body 2, the first air inlet 1 is connected with an outer cavity body through four tangential flue gas inlet pipelines, the cavity body between the outer cylinder body 2 and the middle cylinder body 3 is an outer cavity body, an absorption liquid collecting tank 14 and an absorption liquid discharge pipeline 15 are formed in the lower portion of the outer cavity body, an alkaline water spraying pipeline (a first absorption liquid annular pipeline 6) and an atomizing nozzle (an outer cavity body nozzle 5) are uniformly arranged in the upper area; a tangential air inlet channel (a second air inlet 7) is arranged at the upper part of the middle cylinder body 3, a cavity between the middle cylinder body 3 and the inner cylinder body 4 is a middle cavity, and a second absorption liquid annular pipeline 12 and an atomizing nozzle are uniformly arranged at the upper part of the middle cavity; the lower part of the inner cylinder 4 is provided with an annular grid 13, the annular grid 13 is a channel for communicating the inner cavity with the lower end of the middle cavity, the annular grid 13 is uniformly distributed along the inner cylinder 4, the flue gas enters the inner cavity formed by the inner cylinder 4 through the annular grid 13, the lower part of the inner cavity is provided with a conical absorption liquid collecting tank (a second liquid collecting tank 16), the lowest end of the collecting tank is connected with a liquid discharge pipe 17, the liquid discharge pipe 17 is connected with an inverted U-shaped pipe 20, and the inlet and the outlet of the inverted U-shaped pipe 20 are connected with a liquid discharge control valve 18; the upper part of the inner cylinder 4 is provided with a W-shaped demister 11, and a washer 10 formed by a flushing water pipeline and a spray head is uniformly arranged on the demister 11; the upper end of the inner cylinder body 4 is connected with an exhaust pipeline.

The flue gas that will handle gets into from first air inlet 1, because the angle of flue gas air inlet and outer barrel 2 is the tangential direction, therefore the flue gas is the heliciform in the outer cavity and rises, forms the convection current with the alkaline absorption liquid that upper portion outer cavity shower nozzle 5 sprayed down, and the two intensive mixing absorbs, and the dirt granule is fully moist, and droplet and moist smoke and dust particle fall to the first collecting tank 14 of outer cavity lower extreme under the effect of gravity in, discharge to the outer jar through recovery tube 15.

This novel well outer cavity shower nozzle 5 blowout sodium hydroxide (also can be sodium carbonate) solution, sodium hydroxide can react with the sulfur dioxide in the flue gas and generate sodium sulfite solution, the solution after the absorption is sprayed in the outer chamber is called first absorption liquid, first absorption liquid is collected in first collecting tank 14, discharge outer jar through recovery tube 15, the pH value of control first absorption liquid, make and contain the sodium sulfite solution of higher concentration in the first absorption liquid, because the concentration of sodium sulfite solution mainly depends on the reaction of sodium hydroxide solution and sulfur dioxide, consequently this can be realized through the concentration and the speed of controlling outer cavity shower nozzle 5 spun sodium hydroxide solution, thereby make the pH value of first absorption liquid maintain in 7-8 lower within range. The recovered first absorption liquid is used for producing a sodium sulfite product, so that the first absorption liquid has higher sodium sulfite concentration and lowest sodium hydroxide, sodium carbonate or sodium bisulfite concentration, which can ensure that excessive impurities are prevented from being introduced when the first absorption liquid is used for producing sodium sulfite, the purity of the sodium sulfite product is improved, and a high-quality sodium sulfite product can be obtained.

The flue gas rising to the upper part of the outer cavity enters the middle cavity through the phase-cutting flue (a second air inlet 7), is mixed and absorbed with the sprayed alkali liquor on the upper part of the middle cavity in a turbulent state, flows to the bottom of the middle cavity together in a rotating manner, is contacted with the second absorption liquid at the bottom, the annular grid 13 is sealed by the second absorption liquid, bubbling can be formed when the flue gas passes through the annular grid 13, the flue gas enters the inner cavity through a channel of the annular grid 13, in the process of passing through the liquid-sealed liquid, the flue gas is further washed, sulfur dioxide is further absorbed to generate a sodium sulfate solution, and smoke particles are wetted and remained in a liquid phase. The pH value of the solution used by the second absorption liquid is high (10-11), and the second absorption liquid is strong alkaline, so that the sulfur dioxide in the flue gas can be fully absorbed, and the emission standard can be met.

The gas passing through the annular grating 13 is also provided with partial small liquid drops, the small liquid drops are separated from the flue gas under the action of gravity in the ascending process and fall into the second absorption liquid at the lower part, and small liquid drops which are not separated by the gravity are gathered into large liquid drops by the demister 11 and fall into the lower end of the demister when passing through the W-shaped demister 11 and fall into the lower end of the inner cavity by the gravity; the purified flue gas enters the chimney through the smoke exhaust pipe to be emptied.

For preventing that defroster 11 long-time running from leading to the fact the circulation resistance to rise when blockking up, this is novel installs scrubber 10 on 11 upper portions of defroster for wash defroster 11, make the deposit on defroster upper portion dissolve, prevent to block up. The working condition of the inner cylinder 4 can be checked through the inspection hole 9.

The function of the inverted U-shaped pipe 20 is to control the liquid level of the lower parts of the middle cavity and the inner cavity, so that the liquid level absorbing the second absorption liquid is higher than the height of the annular grid 13, and the flue gas can be fully contacted with alkali liquor, bubbled, washed and absorbed when passing through the grid 13; the liquid discharge control valve 18 is used for discharging absorption liquid at the lower ends of the hollow cavity and the inner cavity during maintenance and has the function of fine adjustment of liquid level.

This novel external circulation system that has increased, as shown in figure 1, this external circulation system mainly used improves the utilization ratio of sodium hydroxide solution/sodium carbonate solution, and on the other hand easily adjusts the pH value of first absorption liquid.

The external circulation system comprises an external circulation tank 22, the external circulation tank 22 is connected with the recovery pipe 15, an external circulation tank pH meter 21 and an external circulation tank liquid level meter 23 can be arranged in the external circulation tank 22, the external circulation tank 22 is connected with the first absorption liquid annular pipeline 6 through an external circulation pipe 25, and an external circulation pump 24 is connected to the external circulation pipe 25.

In the novel process, the PH value of the first absorption liquid needs to be maintained at a lower level, and therefore an alkaline solution with lower PH needs to be continuously sprayed into the cavity, so that on one hand, a large amount of alkaline solution needs to be consumed, and on the other hand, the alkaline solution cannot completely react with sulfur dioxide, so that the problem of low utilization efficiency of the alkaline solution is caused; and the concentration and the speed of the sodium hydroxide solution sprayed by the outer cavity spray head 5 are not easy to control, and the pH value of the first absorption liquid is not easy to adjust.

The first absorption liquid absorbs flue gas from a process source, ensures that sodium carbonate in the absorption liquid is converted into sodium sulfite, and is controlled to have a pH value of 7.0-8; if the pH value is controlled to be about 5.6, the final product is sodium bisulfite, and if the pH value is controlled to be low, the equipment is corroded, and the requirement on the material is higher; the first absorption liquid ensures that the absorption liquid contacts the flue gas with higher sulfur dioxide content, and the absorption liquid is easy to reach the absorption end point; after the absorption liquid reaches the end point, most of the absorption liquid is transferred to the next process.

The problems are effectively overcome by adding an external circulation system. After having increased outer circulation system, first absorption liquid is after reacting with the flue gas, absorb the sulfur dioxide in the flue gas, generate sodium sulfite, first absorption liquid passes through the pipeline and gets into outer circulation tank 22, send into outer cavity again through outer circulation pump 24 and absorb once more, so relapse, first absorption liquid constantly absorbs sulfur dioxide and generates sodium sulfite, consequently, the pH value of first absorption liquid can reduce gradually, when the pH value of first absorption liquid reduces to the threshold value, for example can be less than 7.5, add sodium hydroxide solution (also can be sodium carbonate) in the outer circulation tank 22 this moment, in order to maintain the pH value of solution in outer circulation tank 22, make it be higher than the threshold value. Thus, as the production proceeds, the concentration of sodium sulfite in the external circulation tank 22 gradually increases, and the level of the solution in the external circulation tank 22 also gradually increases, and when the level of the solution is greater than a certain value, the solution in the external circulation tank 22 can be transferred to a sodium sulfite production plant to produce sodium sulfite.

In the previous description, numerous specific details were set forth in order to provide a thorough understanding of the present invention. The foregoing description is only illustrative of the preferred embodiments of this invention and, therefore, the invention is not limited to the specific details disclosed herein, since the invention can be practiced in many other ways than those specifically described herein. While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. Any simple modification, equivalent change and modification made to the above embodiments according to the novel technical substance are still within the protection scope of the novel technical scheme.

Claims

1. An external circulation flue gas dust removal and desulfurization device is characterized by comprising an outer cylinder, a middle cylinder, an inner cylinder and an external circulation system, wherein the middle cylinder is positioned between the outer cylinder and the inner cylinder, so that an outer cavity, a middle cavity and an inner cavity are sequentially formed from outside to inside;

the bottom of the outer cylinder is provided with a first air inlet which is communicated with the outer cavity, the top of the outer cavity is provided with an outer cavity spray head, the outer cavity spray head is connected with a first absorption liquid annular pipeline, the bottom of the outer cavity is provided with a first liquid collecting tank, and the bottom of the first liquid collecting tank is connected with a recovery pipe;

a second air inlet is formed in the top of the middle cylinder, the outer cavity is communicated with the middle cavity through the second air inlet, a middle cavity spray head is arranged at the top of the middle cavity, and the middle cavity spray head is connected with a second absorption liquid annular pipeline;

a third air inlet is formed in the bottom of the inner cylinder body, the middle cavity is communicated with the inner cavity through the third air inlet, and an annular grid is arranged at the third air inlet;

the external circulation system comprises an external circulation tank, the external circulation tank is connected with the recovery pipe, and the external circulation tank is further connected with the first absorption liquid annular pipeline through an external circulation pipe.

2. The flue gas dust removal and desulfurization device of claim 1, wherein a second liquid collection tank is arranged at the bottom of the inner cavity, and a liquid discharge pipe is connected to the bottom of the second liquid collection tank.

3. The flue gas dust removal and desulfurization device of claim 2, wherein the liquid discharge pipe extends to the outside of the desulfurization device and is connected with an inverted U-shaped pipeline, and a clean discharge pipeline is arranged at the bottom of the inverted U-shaped pipeline.

4. The flue gas dust removal and desulfurization device of claim 1, wherein a demister is arranged at the upper part of the inner cavity, and a scrubber is installed above the demister.

5. The flue gas dust removal and desulfurization device of claim 1, wherein the first gas inlet is connected to the outer chamber body by four tangential flue gas inlet ducts.

6. The flue gas dust removal and desulfurization device of claim 1, wherein the first absorption liquid is a sodium hydroxide or sodium carbonate solution; the second absorption liquid is sodium hydroxide or sodium carbonate solution.

7. The flue gas dust removal and desulfurization device of claim 6, wherein the pH value of the first absorption liquid is 7-8; the pH value of the second absorption liquid is 10-11.

8. The flue gas dust removal and desulfurization device of claim 1, wherein an external circulation tank pH meter is arranged in the external circulation tank.

9. The flue gas dust removal and desulfurization device of claim 1, wherein an external circulation tank level gauge is provided in the external circulation tank.

10. The flue gas dust removal and desulfurization device of claim 1, wherein an external circulation pump is installed on the external circulation pipe.