CN216825633U

CN216825633U - Double-circulation flue gas dust removal and desulfurization device

Info

Publication number: CN216825633U
Application number: CN202220396553.3U
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 a double-circulation flue gas dust removal and desulfurization device, which comprises an outer cylinder, a middle cylinder, an inner circulation system and an outer 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 outer circulation system is connected with the inner circulation system through a transfer pipe. This is novel through inside and outside dual cycle system, can make alkaline solution by the maximize utilization, has also reduced manufacturing cost simultaneously.

Description

Double-circulation flue gas dust removal and desulfurization device

Technical Field

The utility model relates to a chemical industry equipment, more specifically relates to a dual 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 a dual-cycle flue gas dust removal and desulfurization device.

A dual-circulation flue gas dust removal and desulfurization device comprises an outer cylinder, a middle cylinder, an inner circulation system and an outer 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 barrel, the middle cavity is communicated with the inner cavity through the third air inlet, an annular grid is arranged at the third air inlet, a second liquid collecting tank is arranged at the bottom of the inner cavity, and a liquid discharge pipe is connected to the bottom of the second liquid collecting tank; the outer circulation system is connected with the inner circulation system through a transfer 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 maximized recovery of sodium sulfite can be realized through the internal circulation system. 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. Through the internal and external double circulation systems, the alkaline solution can be maximally utilized, and the production cost is reduced.

Drawings

FIG. 1 is a schematic structural diagram of a dual-cycle flue gas dust removal and desulfurization device;

FIG. 2 is a top view of the dual cycle flue gas dust removal and desulfurization unit.

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 is novel still to have increased inside and outside two circulation system, not only can improve the utilization ratio of sodium hydroxide solution/sodium carbonate solution through this inside and outside circulation system, realizes the maximize of sodium sulfite and retrieves, can also easily adjust the pH value of first absorption liquid, through inside and outside dual cycle system in addition, can make alkaline solution by the maximize utilization, has also reduced manufacturing cost simultaneously.

Specifically, referring to fig. 1, the internal circulation system comprises an internal circulation tank 22, the internal circulation tank 22 is connected with the outlet of an inverted "U" shaped pipe 20, an internal circulation tank PH meter 21 and an internal circulation tank liquid level meter 23 can be arranged in the internal circulation tank 22, the internal circulation tank 22 is connected with the second absorption liquid annular pipeline 12 through an internal circulation pipe 25, and an internal circulation pump 24 is connected with the internal circulation pipe 25.

After the internal circulation system is added, the second absorption liquid is after reacting with the flue gas, absorb the sulfur dioxide in the flue gas, generate sodium sulfite, the sodium sulfite concentration in the second absorption liquid is lower at this moment, the second absorption liquid passes through the pipeline and enters the internal circulation tank 22, be sent into the interior cavity again via the internal circulation pump 24 and absorb once more, so repeatedly, the second absorption liquid constantly absorbs sulfur dioxide and generates sodium sulfite, therefore the pH value of the second absorption liquid can reduce gradually, in order to guarantee the desulfurization effect of flue gas, the pH value of the second absorption liquid can not reduce too much, when the pH value of the second absorption liquid reduces to the threshold value, for example, can be less than 10, add sodium hydroxide solution (also can be sodium carbonate) into the internal circulation tank 22 at this moment, in order to maintain the pH value of the solution in the internal circulation tank 22, make it be higher than the threshold value.

The external circulation system comprises an external circulation tank 27, the external circulation tank 27 is connected with the recovery pipe 15, an external circulation tank pH meter 26 and an external circulation tank liquid level meter 28 can be arranged in the external circulation tank 27, the external circulation tank 27 is connected with the first absorption liquid annular pipeline 6 through an external circulation pipe 30, and an external circulation pump 29 is connected with the external circulation pipe 30.

In production, the pH value of the first absorption liquid needs to be maintained at a lower level, so that an alkaline solution with lower pH needs to be continuously sprayed into the outer cavity, 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 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 27, send into outer cavity again through outer circulation pump 30 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 27 this moment, in order to maintain the pH value of solution in outer circulation tank 27, make it be higher than the threshold value.

The external circulation system and the internal circulation system are connected to each other by a transfer pipe 31 to form a double circulation system, and specifically, the transfer pipe 31 is provided between the external circulation tank 27 and the internal circulation tank 22, the external circulation tank 27 and the internal circulation tank 22 are communicated by the transfer pipe 31, and a transfer pump 32 is provided in the transfer pipe 31.

When the solution level is higher than a certain value, the transfer pump 32 is started, the solution in the internal circulation tank 22 is transferred to the external circulation tank 27 through the transfer pipe 31, and the solution in the internal circulation tank 22 is mixed with the solution in the external circulation tank 27 to form a mixed solution. It should be noted that although mixing the solution in the internal circulation tank 22 and the solution in the external circulation tank 27 will increase the PH of the mixed solution in the external circulation tank 27, since the volume of the external circulation tank 27 is much larger than that of the internal circulation tank 22, and the first absorption liquid with relatively low PH is mainly in the external circulation tank 27, the PH of the mixed solution (the first absorption liquid) in the external circulation tank 27 will not be increased so much due to the mixing, and the PH of the mixed solution (the first absorption liquid) in the external circulation tank 27 will still meet the production requirement as a result of the mixing.

In addition, after the first absorption liquid reaches the end point, most of the first absorption liquid is transferred to the next working procedure (the remained solution cannot influence the normal circulation), and then part of the solution in the second absorption liquid is supplemented into the first absorption liquid, and the vacancy in the second absorption liquid is supplemented by fresh sodium hydroxide or sodium carbonate solution; the second absorption liquid is a solution with a higher PH value to fully absorb the flue gas containing sulfur dioxide, so that the sulfur dioxide is absorbed in the higher alkaline solution as much as possible, and the flue gas is ensured to reach the standard and be discharged; the second absorption liquid contains a small amount of sodium sulfite, the content of the sodium sulfite is continuously increased along with the extension of the absorption time, and the content of alkali is gradually reduced until the sodium sulfite is added into the first absorption liquid; fresh alkaline sodium hydroxide or sodium carbonate solution is then replenished. The alkali content in the first absorption solution is also such that as the absorption proceeds the sodium carbonate solution content gradually decreases, the sodium sulfite solution gradually increases and the PH gradually decreases to reach a PH of 7.0-8, e.g. 7.5, essentially ending with a solution essentially of sodium sulfite containing a small amount of sodium carbonate or sodium bisulfite.

Then the mixed liquid becomes a first absorption liquid and enters an external circulation system for flue gas desulfurization treatment, so that the concentration of the sodium sulfite in the external circulation tank 27 is gradually increased along with the production, the liquid level of the solution in the external circulation tank 27 is also gradually increased, and when the liquid level of the solution is greater than a certain value, the first absorption liquid is finally discharged to a sodium sulfite production workshop from an outlet 33 at the bottom of the external circulation tank 27. The external circulation tank 27 is communicated with the internal circulation tank 22 through the transfer pipe 31, which enables the alkaline solution to be maximally utilized while also reducing the production cost.

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 a preferred embodiment of the invention, which can be embodied in many different forms and is therefore not limited to the specific embodiments disclosed above. 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. A dual-cycle flue gas dust removal and desulfurization device is characterized by comprising an outer cylinder, a middle cylinder, an inner circulation system and an outer 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 barrel, the middle cavity is communicated with the inner cavity through the third air inlet, an annular grid is arranged at the third air inlet, a second liquid collecting tank is arranged at the bottom of the inner cavity, and a liquid discharge pipe is connected to the bottom of the second liquid collecting tank;

the outer circulation system is connected with the inner circulation system through a transfer pipe, and a transfer pump is arranged on the transfer pipe.

2. The flue gas dust removal and desulfurization device of claim 1, wherein 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.

3. The flue gas dust removal and desulfurization device of claim 1, wherein the internal circulation system comprises an internal circulation tank, the internal circulation tank is connected with the liquid discharge pipe, and the internal circulation tank is further connected with the second absorption liquid annular pipeline through an internal circulation pipe.

4. The flue gas dust removal and desulfurization device of claim 1, wherein when the liquid level of the internal circulation system exceeds a set height, the transfer pump is started to transfer the solution of the internal circulation system to the external circulation system through the transfer pipe.

5. The flue gas dust removal and desulfurization device of claim 1, wherein the drain pipe extends to the outside of the desulfurization device and is connected with an inverted U-shaped pipeline, and a drain pipeline is arranged at the bottom of the inverted U-shaped pipeline.

6. The flue gas dust removal and desulfurization device of claim 1, wherein the external circulation system comprises an external circulation tank, the internal circulation system comprises an internal circulation tank, and the volume of the external circulation tank is larger than that of the internal circulation tank.

7. 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.

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

9. 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.

10. 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.