Gas treatment apparatus

Abstract

To provide a gas treatment apparatus which efficiently separates and recovers recovered gas in treatment in a gas to be treated with less energy by a simple structure.SOLUTION: A gas treatment apparatus has a treatment tower which stores a treatment liquid, and has a nozzle for blowing a gas to be treated into the treatment liquid provided on its lower part, in which in the treatment tower, a partition plate for partitioning the treatment tower into a nozzle region including a blowout hole of the nozzle and other regions other than the nozzle region in a vertical direction is provided in a range excluding the upper end of the treatment tower.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an apparatus for separating and recovering specific gas components such as carbon dioxide (hereinafter referred to as "gas to be recovered") from a gas to be treated such as exhaust gas. [Background technology]

[0002] Carbon dioxide is a greenhouse gas that causes global warming, and therefore research is being conducted into techniques for separating and recovering carbon dioxide from combustion gases, etc. Patent Document 1 discloses a carbon dioxide gas recovery device that brings a gas to be treated into contact with a lean absorbing solution capable of absorbing carbon dioxide gas in an absorption tower, causes the carbon dioxide gas in the gas to be treated to be absorbed by the lean absorbing solution to generate a rich absorbing solution, and heats the rich absorbing solution in a regeneration tower to separate and recover carbon dioxide as a gas.

[0003] In the above-mentioned device, an aqueous solution of isopropylaminoethanol or the like is used as an absorbing liquid, and when the gas to be treated is brought into contact with the absorbing liquid in the absorption tower, the carbon dioxide gas is selectively absorbed into the absorbing liquid to become a rich absorbing liquid. Next, when this rich absorbing liquid is heated in the regeneration tower, the carbon dioxide in the rich absorbing liquid is separated as a gas, and the separated carbon dioxide gas is recovered.

[0004] In addition, examples of treatment liquids that absorb carbon dioxide from the gas to be treated and separate it as a solid precipitate include isophorone diamine and calcium hydroxide aqueous solution. When using these treatment liquids, it is possible to separate carbon dioxide as a solid precipitate, heat and decompose this solid precipitate by batch processing, and recover the carbon dioxide gas. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2015-131735 A Summary of the Invention [Problem to be solved by the invention]

[0006] In the technology described in the above Patent Document 1, since carbon dioxide is absorbed in the lean absorbing solution, it is necessary to send all of the rich absorbing solution that has absorbed carbon dioxide to a regenerator and heat it to separate the carbon dioxide, which causes problems such as the increase in size of the absorption tower and the regenerator, and the complexity of the equipment. There is also a problem that a lot of energy is consumed to move and heat the rich absorbing solution and the lean absorbing solution.

[0007] Furthermore, when carbon dioxide is separated as a solid precipitate, it is expected that the treatment device will be made smaller, but since the decomposition of the solid precipitate is carried out in a batch process, there is a problem in improving the efficiency of the treatment.

[0008] An object of the present disclosure is to provide a gas treatment device that has a simple structure and that separates and recovers a gas to be recovered from a gas to be treated efficiently with little energy. [Means for solving the problem]

[0009] The gas treatment device of the present disclosure has a treatment tower that contains a treatment liquid and has a nozzle at the bottom that injects a gas to be treated into the treatment liquid, and the treatment tower is provided with a partition plate that vertically divides the treatment tower into a nozzle area including the nozzle outlet hole and other areas, in an area excluding the upper end of the treatment tower. Effect of the Invention

[0010] According to the gas treatment device of the present disclosure, a treatment liquid containing a reactive component that reacts with the gas to be recovered in the gas to be treated and precipitates as a solid precipitate is placed in a treatment tower, and the gas to be treated is blown into the treatment liquid from a nozzle to bring the gas to be treated into contact with the treatment liquid, whereby the gas to be recovered reacts with the reactive component in the treatment liquid and precipitates as a solid precipitate. When the bubbles of the gas to be treated rise in the nozzle region, the solid precipitate also rises. When the solid precipitate reaches the top of the other region, it descends the other region and settles at the bottom of the treatment tower, so that the solid precipitate can be easily extracted continuously. [Brief description of the drawings]

[0011] [Figure 1] FIG. 2 is a schematic diagram showing a gas treatment device. [Diagram 2] FIG. 2 is a schematic diagram showing details of a treatment tower. [Diagram 3] FIG. 2 is a schematic diagram showing the operation of the gas treatment device. [Figure 4] FIG. 13 is a schematic diagram showing a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. Fig. 1 is a schematic diagram showing an example of a gas treatment device 1 of the present disclosure. The gas treatment device 1 has a treatment tower 10, a regenerator 30, and a communication pipe 40 that connects the treatment tower 10 and the lower part of the regenerator 30.

[0013] The main body 11 of the treatment tower 10 is a container having a substantially cylindrical or rectangular shape capable of containing the treatment liquid 19 therein, and has a discharge hole 13 formed at the top for discharging the treated gas. The bottom wall 15 of the treatment tower 10 slopes downward as it approaches the portion where the communicating pipe 40 described below is connected.

[0014] A nozzle 17 is provided at the bottom of the treatment tower 10 for blowing the target gas such as exhaust gas into the treatment tower 10. The nozzle 17 has an injection hole configured to inject the target gas from a large number of small holes so that the target gas is blown in as fine bubbles.

[0015] 2, the treatment tower 10 is divided into a nozzle region 27 and other regions 29 by a partition plate 21. The partition plate 21 is a flat plate having a height approximately half that of the treatment tower 10, and is provided in the vertical direction at the middle part of the height direction of the treatment tower 10. The inside of the treatment tower 10 is divided into a nozzle region 27 where the nozzles 17 are located, and other regions 29, and the nozzle region 27 and other regions 29 are connected above and below the partition plate 21.

[0016] A tubular member 23 is provided in the vertical direction above the nozzle 17 in the nozzle region 27. The diameter of the tubular member 23 is larger than that of the nozzle 17, and is formed and arranged so that almost all of the bubbles of the gas to be treated blown from the nozzle 17 into the treatment liquid 19 enter the tubular member 23.

[0017] A straightening plate 25 inclined toward the other region 29 is provided at the upper end of the tubular member 23, and configured so that air bubbles floating up inside the tubular member 23 are guided toward the other region 29. The straightening plate 25 has a size that extends from the nozzle region 27 beyond the partition plate 21 and covers approximately half of the other region 29.

[0018] 1, the regenerator 30 is a container having a substantially cylindrical or rectangular shape capable of accommodating the treatment liquid 39 therein, and has a recovery hole 33 formed in the upper portion for discharging and recovering the gas to be recovered separated from the solid precipitate. The bottom wall 35 of the regenerator 30 is formed in a substantially concave shape so as to accumulate the solid precipitate moving through a communication pipe 40 described later.

[0019] The regeneration tower 30 is provided with a heating device 37. The heating device 37 is for thermally decomposing the precipitated solid matter. The heating temperature depends on the type of gas to be treated and the treatment liquid 39, but when carbon dioxide is precipitated as a solid matter by an aqueous isophoronediamine solution, it is preferable to heat to about 60 degrees.

[0020] A communication pipe 40 that communicates between the inside of the treatment tower 10 and the inside of the regenerator 30 is connected to the lower part of the treatment tower 10 and the regenerator 30. The communication pipe 40 is inclined so that the regenerator 30 side is lower so that solid precipitate that has settled on the bottom wall 15 of the treatment tower 10 enters the communication pipe 40 due to the inclination of the bottom wall 15 and then moves onto the bottom wall 35 of the regenerator 30 by gravity.

[0021] Furthermore, the treatment tower 10 and the regenerator 30 are provided with treatment liquid transfer pipes 42, 44, which are connected by a connecting pipe (not shown). As a result, the treatment tower 10 and the regenerator 30 are in communication with each other via the treatment liquid transfer pipes 42, 44. The treatment liquid transfer pipes 42, 44 are provided with pumps (not shown), which are configured to be able to transfer the treatment liquid 39 in the regenerator 30 into the treatment tower 10.

[0022] The treatment tower 10, regeneration tower 30, and communication pipe 40 are filled with treatment liquids 19, 39 for absorbing the recovered gas from the gas to be treated and separating it as a solid precipitate. When the gas to be treated is a combustion gas and the gas to be recovered is carbon dioxide, isophoronediamine or an aqueous calcium hydroxide solution can be used as the treatment liquid. The treatment liquids 19, 39 are appropriately selected and used depending on the type of recovered gas to be absorbed.

[0023] Next, the operation of the gas treatment device 1 shown in Fig. 3 will be described. With the treatment tower 10, the regenerator 30, and the communicating pipe 40 filled with the treatment liquids 19, 39, the gas to be treated is blown into the treatment liquid 19 from the nozzle 17. Bubbles of the blown gas to be treated rise inside the tubular member 23 and reach the upper part of the other region 29 along the straightening plate 25. In addition, as the bubbles rise inside the tubular member 23, a flow that rises inside the tubular member 23 to the upper part of the other region 29 and a flow that descends inside the other region 29 are generated in the treatment liquid 19.

[0024] The gas to be recovered in the gas to be treated reacts with the treatment liquid 19 to form solid precipitates, which are carried by the flow of the treatment liquid 19 and rise within the tubular member 23 together with the air bubbles, and reach the upper part of the other region 29 .

[0025] The air bubbles that reach the upper part of the other region 29 along the straightening vane 25 pass through the upper end of the straightening vane 25, reach the liquid surface of the treatment liquid 19, and are discharged to the outside of the treatment tower 10 through the discharge hole 13. On the other hand, the solid precipitate that reaches the upper part of the other region 29 descends in the other region 29 along with the flow of the treatment liquid 19 descending in the other region 29.

[0026] The solid precipitate that has descended and settled in the other area 29 is guided by gravity along the inclination of the bottom wall 15 into the communicating pipe 40 and moves up to above the bottom wall 35 of the regenerator 30. The movement of the solid precipitate is achieved by its own weight, without any external action such as a pump.

[0027] In the regenerator 30, the solid precipitate 50 that has settled on the bottom wall 35 is heated by the heater 37. When the heater 37 heats the treatment liquid 39 in the regenerator 30, the treatment liquid 39 flows, and the heated treatment liquid 39 heats and lifts up the solid precipitate 50 on the bottom wall 35. The heated solid precipitate 50 decomposes, and the gas to be recovered is collected as a gas above the regenerator 30 and recovered from the recovery hole 33.

[0028] As the treatment progresses, the concentration of the treatment liquid 19 in the treatment tower 10 decreases, and the concentration of the treatment liquid 39 in the regenerator 30 increases. Therefore, the treatment liquid 39 in the regenerator 30 is sent to the treatment tower 10 through treatment liquid transfer pipes 42, 44 by a pump (not shown). This makes it possible to maintain the concentrations of the treatment liquid 19 in the treatment tower 10 and the treatment liquid 39 in the regenerator 30 approximately constant, so that the gas to be treated can be continuously blown in and the gas to be recovered can be continuously recovered.

[0029] (Modification) In the above example, the solid precipitate that has settled on the bottom wall 15 of the treatment tower 10 is configured to move by its own weight through the communicating pipe 40 to the regenerator 30, but a pump or the like may be provided to send the solid precipitate from the treatment tower 10 to the regenerator 30. Also, the solid precipitate may be decomposed by another decomposition device instead of using a regenerator.

[0030] (Comparative Example) 4 shows a comparative example in which the partition plate 21 is not provided in the treatment tower 10. When the gas to be treated is blown into the treatment liquid 19 from the nozzle 17 provided at the bottom of the treatment tower 10, bubbles of the gas to be treated rise in the treatment liquid 19. As a result, a flow that stirs the entire treatment liquid 19 in the treatment tower 10 is generated. Since the solid precipitates are very fine particles, they do not settle easily, and the recovery of the gas to be recovered does not progress easily.

[0031] The gas treatment device of the present disclosure is not limited in any way to the gas to be treated or the recovered gas to be separated, so long as it can separate the recovered gas as a solid precipitate using a treatment liquid, in addition to separating carbon dioxide from exhaust gas. [Industrial Applicability]

[0032] This is suitably applicable to cases where a gas to be recovered is separated from a gas to be treated and recovered. [Explanation of symbols]

[0033] 1 Gas treatment equipment 10 Processing Tower 21 Partition 23 Tubular member 25 Rectifier plate 30 Regeneration Tower 40 Communication pipe 42 Processing liquid transfer pipe 44 Processing liquid transfer pipe

Claims

1. a treatment tower containing a treatment liquid and having a nozzle at a lower portion for blowing a gas to be treated into the treatment liquid; The treatment tower is provided with a partition plate that vertically divides the treatment tower into a nozzle region including the nozzle outlet and other regions, except for the upper end of the treatment tower. Gas treatment equipment.

2. An exhaust hole for exhausting the treated gas is formed at the top of the treatment tower. The gas treatment device of claim 1 .

3. a treatment tower containing a treatment liquid and having a nozzle at its lower part for blowing the gas to be treated into the treatment liquid; a regeneration tower provided with a heating device; a communication pipe that communicates the lower part of the treatment tower with the lower part of the regeneration tower and is inclined so as to become lower from the treatment tower side toward the regeneration tower side; having The treatment tower is provided with a partition plate that vertically divides the treatment tower into a nozzle region including the nozzle outlet and other regions, except for the upper end of the treatment tower. Gas treatment equipment.

4. The bottom wall of the treatment tower is inclined so as to become lower toward the connection portion with the communicating pipe. The gas treatment device of claim 3.

5. a discharge hole for discharging the treated gas is formed at the top of the treatment tower; A recovery hole for recovering the gas to be recovered is formed at the top of the regeneration tower. The gas treatment device of claim 3.

6. A treatment liquid transfer pipe for transferring a treatment liquid from the regeneration tower to the treatment tower is provided. The gas treatment device of claim 3.

7. The treatment tower is provided with a guide member that guides the gas blown from the nozzle hole to above the other region via above the partition plate. The gas treatment device according to any one of claims 1 to 6.

8. The guide member includes a tubular member provided in the vertical direction, and a baffle plate provided at an upper end of the tubular member to guide the gas to an upper portion of the other region. The gas treatment device of claim 7.

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