Tail gas recovery device for preparing dry ice

Abstract

The invention relates to the technical field of dry ice tail gas recovery, and discloses a tail gas recovery device for preparing dry ice, which comprises a tail gas pipe, the left end of the tail gas pipe is communicated with a tail gas outlet of dry ice production equipment, the right end of the tail gas pipe is communicated with an adsorption tower, and a carbon dioxide adsorption part is fixedly mounted in the adsorption tower. Carbon dioxide in tail gas is adsorbed through a carbon dioxide adsorption part in an adsorption tower, then the carbon dioxide is collected through a collecting cover, collected carbon dioxide gas flow enters a communicating pipe along an output pipe and then is guided into a compressor after being pressurized by a booster pump, the carbon dioxide gas is compressed through the compressor, and the compressed carbon dioxide gas flows into the tail gas. Compared with the mode that tail gas is introduced into a compressor, the mode that the tail gas is used as a raw material for preparing dry ice can purify the tail gas and increase the content of carbon dioxide, and then the high-temperature liquid state compressed by the compressor can meet the requirement for manufacturing the dry ice.

Description

Technical Field

[0001] The invention relates to the technical field of dry ice tail gas recovery, in particular to a tail gas recovery device for preparing dry ice. Background Art

[0002] During the production process of dry ice, a large amount of dry ice tail gas is released, resulting in low utilization rate of raw material liquid carbon dioxide, causing great waste. The existing solution is to collect the dry ice tail gas into an air bag, then pressurize it through a compressor, and cool and liquefy it through a refrigerator to obtain liquid carbon dioxide. However, during the preparation of dry ice, other gases may be mixed into the tail gas for various reasons. For example, since the equipment cannot achieve an absolute sealed state, a small amount of air may enter the reaction system. During the preparation of dry ice, these air components (mainly nitrogen and oxygen) will be discharged along with the carbon dioxide tail gas. Therefore, directly collecting the carbon dioxide tail gas and then using it as raw material to prepare dry ice will result in impure raw materials and cause the preparation requirements to change. Summary of the invention

[0003] The object of the present invention is to provide an exhaust gas recovery device for preparing dry ice to solve the problems raised in the above background technology.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an exhaust gas recovery device for preparing dry ice, comprising an exhaust pipe, the left end of the exhaust pipe is connected to the exhaust outlet of the dry ice production equipment, the right end of the exhaust pipe is connected to an adsorption tower, a carbon dioxide adsorption component is fixedly installed inside the adsorption tower, a collection cover is arranged above the carbon dioxide adsorption component, the top of the collection cover is connected to an output pipe, the output pipe extends from the adsorption tower, and the right end of the output pipe is connected to a connecting pipe, the top of the adsorption tower is connected to an exhaust pipe, and the A support frame is arranged on the right side of the adsorption tower, a booster pump is fixedly installed on the top of the support frame, an air inlet end of the booster pump is connected with the right end of the connecting pipe, a compressor is fixedly installed on the top of the support frame, a shock-absorbing pad is arranged at the connection between the compressor and the support frame, an air outlet end of the booster pump is connected with the air inlet end of the compressor through a pipeline; the carbon dioxide adsorption component comprises a mounting frame, the mounting frame is fixedly installed on the inner wall of the adsorption tower, a heating plate is fixedly installed on the inner side of the mounting frame, and the gap between the mounting frame and the heating plate is filled with carbon dioxide adsorption filler.

[0005] Furthermore, the boost pump and the compressor communication pipeline passes through a high-pressure storage tank, the high-pressure storage tank is fixedly mounted on a support frame, an air outlet of the high-pressure storage tank is connected with an input pipe, and the input pipe is connected with an air inlet of the compressor.

[0006] Furthermore, valves are provided at the connection point between the exhaust pipe and the adsorption tower, at the connection point between the tail gas pipe and the adsorption tower, and at the connection point between the high-pressure storage tank and the input pipe.

[0007] Furthermore, a sewage pipe is provided at the bottom of the adsorption tower, and a valve is provided at the connection point between the sewage pipe and the adsorption tower.

[0008] Furthermore, a feeding pipe is provided at the bottom of the high-pressure storage tank, a valve is provided at the connection between the feeding pipe and the high-pressure storage tank, a pressure gauge is fixedly installed on the outer wall of the high-pressure storage tank, and the air inlet end of the pressure gauge is connected to the interior of the high-pressure storage tank.

[0009] Furthermore, a cold water tank is fixedly installed on the top of the support frame, the connecting pipe passes through the cold water tank, and a liquid injection pipe is provided on the top of the cold water tank.

[0010] Furthermore, a temperature sensor is fixedly installed on the top of the cold water tank, and the detection end of the temperature sensor extends into the cold water tank. The back of the cold water tank is connected to a hose, and the rear end of the hose is connected to a nozzle.

[0011] Furthermore, a dry ice maker is arranged at the rear of the compressor, the air inlet end of the dry ice maker is connected to the air outlet end of the compressor through a pipeline, a discharge pipe is arranged at the top of the dry ice maker, a dry ice collector is arranged at the rear of the dry ice maker, and the discharge pipe extends into the dry ice collector.

[0012] Furthermore, the connecting pipe includes a front end pipe and a rear end pipe, and a secondary separation box is provided between the front end pipe and the rear end pipe. The secondary separation box is located in the cold water tank, and a selective permeable membrane is fixedly installed inside the secondary separation box. An air outlet pipe is provided on the front and back sides of the secondary separation box, and one end of the air outlet pipe away from the secondary separation box extends out from the cold water tank.

[0013] Furthermore, the selective permeable membrane is a polyimide membrane, the selective permeable membrane is tapered, and the smaller end of the selective permeable membrane faces the rear end tube.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1. The carbon dioxide in the tail gas is adsorbed by the carbon dioxide adsorption component in the adsorption tower, and then the carbon dioxide is collected by the collection hood. The collected carbon dioxide gas flows into the connecting pipe along the output pipe, and then is pressurized by the booster pump and introduced into the compressor. The compressor is used to compress the carbon dioxide gas, and then used as the raw material for preparing dry ice. Compared with the tail gas being introduced into the compressor, this method can purify the tail gas and increase the content of carbon dioxide, so that the high-temperature liquid after being compressed by the compressor can meet the requirements for making dry ice;

[0016] 2. Use the selective permeable membrane in the secondary separation box to purify carbon dioxide for the second time. The carbon dioxide gas can pass through the selective permeable membrane and then enter the rear end pipe. The remaining gas cannot pass through the selective permeable membrane and can only be discharged from the outlet pipe. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the present invention;

[0018] Figure 2 For the present invention Figure 1 A schematic diagram of the structure of the back view;

[0019] Figure 3 It is a structural schematic diagram of a front cross-sectional view of an adsorption tower of the present invention;

[0020] Figure 4 It is a structural schematic diagram of an exploded view of a carbon dioxide adsorption component of the present invention;

[0021] Figure 5 It is a schematic diagram of the structure of the compressor, high-pressure storage tank and booster pump of the present invention;

[0022] Figure 6 It is a structural schematic diagram of a front cross-sectional view of a cold water tank of the present invention;

[0023] Figure 7 It is a structural schematic diagram of the front cross-sectional view of the secondary separation box of the present invention.

[0024] In the figure: 1. tail gas pipe; 2. adsorption tower; 201. sewage pipe; 3. exhaust pipe; 4. carbon dioxide adsorption component; 401. mounting frame; 402. heating plate; 403. carbon dioxide adsorption filler; 5. collecting cover; 6. output pipe; 7. connecting pipe; 701. front end pipe; 702. rear end pipe; 8. booster pump; 9. high pressure storage tank; 901. feeding pipe; 902. pressure gauge; 10. support frame; 11. input pipe; 12. compressor; 13. shock pad; 14. dry ice maker; 1401. discharge pipe; 15. dry ice collector; 16. cold water tank; 1601. injection pipe; 17. temperature sensor; 18. hose; 19. nozzle; 20. secondary separation box; 21. selective permeable membrane; 22. outlet pipe. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0026] Embodiment 1

[0027] See also Figure 1-Figure 5 The present invention provides a technical solution: an exhaust gas recovery device for preparing dry ice, comprising an exhaust pipe 1, the left end of the exhaust pipe 1 is connected to the exhaust outlet of the dry ice production equipment, the right end of the exhaust pipe 1 is connected to an adsorption tower 2, a carbon dioxide adsorption component 4 is fixedly installed inside the adsorption tower 2, a collection cover 5 is arranged above the carbon dioxide adsorption component 4, an output pipe 6 is connected to the top of the collection cover 5, the output pipe 6 extends from the adsorption tower 2, and a connecting pipe 7 is connected to the right end of the output pipe 6, an exhaust pipe 3 is connected to the top of the adsorption tower 2, a support frame 10 is arranged on the right side of the adsorption tower 2, a booster pump 8 is fixedly installed on the top of the support frame 10, the air inlet end of the booster pump 8 is connected to the right end of the connecting pipe 7, and a A compressor 12 is provided with a shock-absorbing pad 13 at the connection between the compressor 12 and the support frame 10. The outlet end of the booster pump 8 is connected to the inlet end of the compressor 12 through a pipeline. The carbon dioxide in the tail gas is adsorbed by the carbon dioxide adsorption component 4 in the adsorption tower 2, and then the carbon dioxide is collected by the collection hood 5. The collected carbon dioxide gas flows along the output pipe 6 into the connecting pipe 7, and then is pressurized by the booster pump 8 and introduced into the compressor 12. The carbon dioxide gas is compressed by the compressor 12 and then used as a raw material for preparing dry ice. Compared with the tail gas being introduced into the compressor 12, this method can purify the tail gas and increase the content of carbon dioxide, so that the high-temperature liquid state after being compressed by the compressor 12 can meet the requirements for manufacturing dry ice;

[0028] The carbon dioxide adsorption component 4 includes a mounting frame 401, which is fixedly mounted on the inner wall of the adsorption tower 2. A heating plate 402 is fixedly mounted on the inner side of the mounting frame 401. A carbon dioxide adsorption filler 403 (metal-organic framework material) is filled in the gap between the mounting frame 401 and the heating plate 402. The mounting frame 401 and the heating plate 402 are provided to provide an attachment position for the carbon dioxide adsorption filler 403. After the carbon dioxide adsorption filler 403 adsorbs carbon dioxide to a certain extent, the heating plate 402 works to heat the carbon dioxide adsorption filler 403, so that the carbon dioxide adsorbed by the carbon dioxide adsorption filler 403 is released and then collected by the collection cover 5.

[0029] The pipeline connecting the booster pump 8 and the compressor 12 passes through the high-pressure storage tank 9, which is fixedly mounted on the support frame 10. The gas outlet of the high-pressure storage tank 9 is connected with an input pipe 11, which is connected with the gas inlet of the compressor 12. The high-pressure storage tank 9 is used to store the carbon dioxide gas pressurized by the booster pump 8, so that a stable carbon dioxide gas flow can be continuously input into the compressor 12, ensuring that the compressor 12 can be in a good working state;

[0030] Valves are provided at the connection points between the exhaust pipe 3 and the adsorption tower 2, the connection points between the tail gas pipe 1 and the adsorption tower 2, and the connection points between the high-pressure storage tank 9 and the input pipe 11, for controlling the closing of the tail gas pipe 1 and the exhaust pipe 3. When the carbon dioxide adsorption component 4 releases carbon dioxide, the tail gas pipe 1 and the exhaust pipe 3 need to be closed, and when the carbon dioxide adsorption component 4 adsorbs carbon dioxide, the tail gas pipe 1 and the exhaust pipe 3 are opened;

[0031] The bottom of the adsorption tower 2 is connected with a drain pipe 201, and a valve is provided at the connection between the drain pipe 201 and the adsorption tower 2, because the low-temperature water vapor and the like that enter the adsorption tower 2 along with the tail gas, the water vapor condenses in the adsorption tower 2 and needs to be discharged regularly;

[0032] A feeding pipe 901 is provided at the bottom of the high-pressure storage tank 9, and a valve is provided at the connection between the feeding pipe 901 and the high-pressure storage tank 9. When the tail gas cannot extract enough carbon dioxide to be input into the high-pressure storage tank 9, in order to ensure the operation of the compressor 12, it is necessary to supplement carbon dioxide into the high-pressure storage tank 9 from the feeding pipe 901. A pressure gauge 902 is fixedly installed on the outer wall of the high-pressure storage tank 9. The air inlet end of the pressure gauge 902 is connected to the inside of the high-pressure storage tank 9, and is used to monitor the air pressure in the high-pressure storage tank 9 to avoid danger caused by excessive air pressure in the high-pressure storage tank 9.

[0033] A cold water tank 16 is fixedly installed on the top of the support frame 10, and the connecting pipe 7 passes through the cold water tank 16. A liquid injection pipe 1601 is connected to the top of the cold water tank 16. When the carbon dioxide adsorption filler 403 is heated by the heating plate 402 to release carbon dioxide, the temperature of the carbon dioxide itself is relatively high (60°C-80°C). In order to avoid the problem of high temperature inside the high-pressure storage tank 9 caused by the high-temperature carbon dioxide being input into the high-pressure storage tank 9 after being pressurized by the booster pump 8, the carbon dioxide flowing through the connecting pipe 7 is cooled by the cold water in the cold water tank 16, and a liquid injection pipe 1601 is provided to replenish cold water into the cold water tank 16;

[0034] A temperature sensor 17 is fixedly installed on the top of the cold water tank 16. The detection end of the temperature sensor 17 extends into the cold water tank 16 to monitor the temperature of the water in the cold water tank 16. When the temperature of the cold water rises to the point where the carbon dioxide cannot be cooled quickly, it is necessary to add cold water to the cold water tank 16. A hose 18 is provided at the back of the cold water tank 16. A nozzle 19 is provided at the rear end of the hose 18. The heated water in the cold water tank 16 is introduced into the nozzle 19 through the hose 18. The nozzle 19 sprays the water onto the equipment to be cleaned to clean the equipment.

[0035] A dry ice maker 14 is arranged at the rear of the compressor 12. The air inlet end of the dry ice maker 14 is connected to the air outlet end of the compressor 12 through a pipeline. A discharge pipe 1401 is arranged at the top of the dry ice maker 14. A dry ice collector 15 is arranged at the rear of the dry ice maker 14. The discharge pipe 1401 extends into the dry ice collector 15. The liquid carbon dioxide compressed by the compressor 12 is condensed and decompressed by the dry ice maker 14, so that the liquid carbon dioxide is quickly solidified into dry ice, and the dry ice is collected and stored by the dry ice collector 15.

[0036] Working principle: When in use, the exhaust gas of the dry ice production equipment enters the adsorption tower 2 from the exhaust pipe 1, and then rises along the inside of the adsorption tower 2. When it flows through the carbon dioxide adsorption component 4, the carbon dioxide therein is adsorbed by the carbon dioxide adsorption filler 403 in the carbon dioxide adsorption component 4, and the remaining gas is discharged from the exhaust pipe 3. After the carbon dioxide adsorption filler 403 adsorbs enough carbon dioxide, the valves on the exhaust pipe 1 and the exhaust pipe 3 are closed, and the heating plate 402 is turned on to heat the carbon dioxide adsorption filler 403, so that the carbon dioxide adsorption filler 403 releases carbon dioxide. The carbon dioxide is collected by the collection cover 5 and enters the output pipe 6, and then flows into the connecting pipe 7. The booster pump 8 works to draw the carbon dioxide in the connecting pipe 7 and then pressurizes it into the high-pressure storage tank 9. The high-pressure storage tank 9 opens the valve at the outlet end, so that the carbon dioxide enters the compressor 12 from the input pipe 11. The compressor 12 works to compress the carbon dioxide gas into high-pressure carbon dioxide liquid. The carbon dioxide liquid enters the dry ice maker 14 and is made into dry ice by the dry ice maker 14.

[0037] Embodiment 2

[0038] See also Figure 1-Figure 7The present invention provides a technical solution: an exhaust gas recovery device for preparing dry ice, comprising an exhaust pipe 1, the left end of the exhaust pipe 1 is connected to the exhaust outlet of the dry ice production equipment, the right end of the exhaust pipe 1 is connected to an adsorption tower 2, a carbon dioxide adsorption component 4 is fixedly installed inside the adsorption tower 2, a collection cover 5 is arranged above the carbon dioxide adsorption component 4, the top of the collection cover 5 is connected to an output pipe 6, the output pipe 6 extends from the adsorption tower 2, and the right end of the output pipe 6 is connected to a connecting pipe 7, the top of the adsorption tower 2 is connected to an exhaust pipe 3, and a support frame 10 is arranged on the right side of the adsorption tower 2, A booster pump 8 is fixedly installed on the top of the support frame 10, and the air inlet end of the booster pump 8 is connected to the right end of the connecting pipe 7. A compressor 12 is fixedly installed on the top of the support frame 10, and a shock-absorbing pad 13 is provided at the connection between the compressor 12 and the support frame 10. The air outlet end of the booster pump 8 is connected to the air inlet end of the compressor 12 through a pipeline; the carbon dioxide adsorption component 4 includes a mounting frame 401, and the mounting frame 401 is fixedly installed on the inner wall of the adsorption tower 2. A heating plate 402 is fixedly installed on the inner side of the mounting frame 401, and the gap between the mounting frame 401 and the heating plate 402 is filled with a carbon dioxide adsorption filler 403;

[0039] The booster pump 8 and the compressor 12 are connected through a pipeline through a high-pressure storage tank 9, which is fixedly mounted on a support frame 10. The outlet of the high-pressure storage tank 9 is connected with an input pipe 11, which is connected to the inlet of the compressor 12.

[0040] Valves are provided at the connection point between the exhaust pipe 3 and the adsorption tower 2, at the connection point between the tail gas pipe 1 and the adsorption tower 2, and at the connection point between the high-pressure storage tank 9 and the input pipe 11;

[0041] The bottom of the adsorption tower 2 is connected to a sewage pipe 201, and a valve is provided at the connection between the sewage pipe 201 and the adsorption tower 2;

[0042] A feeding pipe 901 is provided at the bottom of the high-pressure storage tank 9, a valve is provided at the connection between the feeding pipe 901 and the high-pressure storage tank 9, a pressure gauge 902 is fixedly installed on the outer wall of the high-pressure storage tank 9, and the air inlet end of the pressure gauge 902 is connected to the inside of the high-pressure storage tank 9;

[0043] A cold water tank 16 is fixedly installed on the top of the support frame 10, and the connecting pipe 7 passes through the cold water tank 16. A liquid injection pipe 1601 is connected to the top of the cold water tank 16;

[0044] A temperature sensor 17 is fixedly installed on the top of the cold water tank 16, and the detection end of the temperature sensor 17 extends into the cold water tank 16. A hose 18 is connected to the back of the cold water tank 16, and a nozzle 19 is connected to the rear end of the hose 18.

[0045] A dry ice maker 14 is disposed at the rear of the compressor 12. The air inlet of the dry ice maker 14 is connected to the air outlet of the compressor 12 through a pipeline. A discharge pipe 1401 is disposed at the top of the dry ice maker 14. A dry ice collector 15 is disposed at the rear of the dry ice maker 14. The discharge pipe 1401 extends into the dry ice collector 15.

[0046] The connecting pipe 7 includes a front end pipe 701 and a rear end pipe 702. A secondary separation box 20 is connected between the front end pipe 701 and the rear end pipe 702. The secondary separation box 20 is located in the cold water tank 16. A selective permeable membrane 21 is fixedly installed inside the secondary separation box 20. An outlet pipe 22 is connected to the front and back of the secondary separation box 20. One end of the outlet pipe 22 away from the secondary separation box 20 extends out of the cold water tank 16. The selective permeable membrane 21 in the secondary separation box 20 is used to perform secondary purification of carbon dioxide. The carbon dioxide gas can pass through the selective permeable membrane 21 and then enter the rear end pipe 702. The remaining gas cannot pass through the selective permeable membrane 21 and can only be discharged from the outlet pipe 22.

[0047] The selective permeable membrane 21 is a polyimide membrane. The selective permeable membrane 21 is conical, and the smaller end of the selective permeable membrane 21 faces the rear end tube 702. The airflow in the front end tube 701 enters the secondary separation box 20 and contacts the selective permeable membrane 21. At this time, the carbon dioxide gas in the airflow passes through the selective permeable membrane 21 and enters the rear end tube 702. The remaining gas will be blocked at the selective permeable membrane 21, and the subsequent airflow kinetic energy is greater than the blocked gas, so this part of the gas can be blown away, so that the gas flows along the inner wall of the selective permeable membrane 21 and is then guided to the outlet pipe 22.

[0048] Working principle: When in use, the tail gas of the dry ice production equipment enters the adsorption tower 2 from the tail gas pipe 1, and then rises along the inside of the adsorption tower 2. When flowing through the carbon dioxide adsorption component 4, the carbon dioxide therein is adsorbed by the carbon dioxide adsorption filler 403 in the carbon dioxide adsorption component 4, and the remaining gas is discharged from the exhaust pipe 3. After the carbon dioxide adsorption filler 403 adsorbs enough carbon dioxide, the valves on the tail gas pipe 1 and the exhaust pipe 3 are closed, and the heating plate 402 is turned on to heat the carbon dioxide adsorption filler 403, so that the carbon dioxide adsorption filler 403 releases carbon dioxide. The carbon dioxide is collected by the collection cover 5 and enters the output pipe 6, and then flows into the connecting pipe 7. The airflow enters the secondary separation box 20 along the front end pipe 701, and the carbon dioxide gas in the airflow enters the rear end pipe 702 through the selective permeable membrane 21, and then is pumped away by the booster pump 8. The remaining gas will be blocked at the selective permeable membrane 21, and the subsequent airflow kinetic energy is greater than the blocked gas, so this part of the gas can be blown away, so that the gas flows along the inner wall of the selective permeable membrane 21, and then is guided to the outlet pipe 22.

[0049] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

Claims

1. A tail gas recovery device for preparing dry ice, comprising a tail gas pipe (1), characterized in that: The left end of the tail gas pipe (1) is connected to the tail gas outlet of the dry ice production equipment, and the right end of the tail gas pipe (1) is connected to an adsorption tower (2). A carbon dioxide adsorption component (4) is fixedly installed inside the adsorption tower (2). A collection cover (5) is arranged above the carbon dioxide adsorption component (4). The top of the collection cover (5) is connected to an output pipe (6). The output pipe (6) extends from the adsorption tower (2), and the right end of the output pipe (6) is connected to a connecting pipe (7). The top of the adsorption tower (2) is connected to an exhaust pipe (3). A support frame (10) is arranged on the right side of the adsorption tower (2). A booster pump (10) is fixedly installed on the top of the support frame (10). 8), the air inlet end of the booster pump (8) is connected to the right end of the connecting pipe (7), a compressor (12) is fixedly installed on the top of the support frame (10), a shock-absorbing pad (13) is provided at the connection between the compressor (12) and the support frame (10), and the air outlet end of the booster pump (8) is connected to the air inlet end of the compressor (12) through a pipeline; the carbon dioxide adsorption component (4) comprises a mounting frame (401), the mounting frame (401) is fixedly installed on the inner wall of the adsorption tower (2), a heating plate (402) is fixedly installed on the inner side of the mounting frame (401), and the gap between the mounting frame (401) and the heating plate (402) is filled with a carbon dioxide adsorption filler (403).

2. The exhaust gas recovery device for preparing dry ice according to claim 1, characterized in that: The pipeline connecting the boost pump (8) and the compressor (12) passes through a high-pressure storage tank (9), and the high-pressure storage tank (9) is fixedly mounted on a support frame (10). The air outlet of the high-pressure storage tank (9) is connected with an input pipe (11), and the input pipe (11) is connected with the air inlet of the compressor (12).

3. The tail gas recovery device for preparing dry ice according to claim 1, characterized in that: Valves are provided at the connection point between the exhaust pipe (3) and the adsorption tower (2), at the connection point between the tail gas pipe (1) and the adsorption tower (2), and at the connection point between the high-pressure storage tank (9) and the input pipe (11).

4. The tail gas recovery device for preparing dry ice according to claim 1, characterized in that: The bottom of the adsorption tower (2) is connected to a sewage discharge pipe (201), and a valve is provided at the connection point between the sewage discharge pipe (201) and the adsorption tower (2).

5. The exhaust gas recovery device for preparing dry ice according to claim 2, characterized in that: A feeding pipe (901) is provided at the bottom of the high-pressure storage tank (9), a valve is provided at the connection between the feeding pipe (901) and the high-pressure storage tank (9), a pressure gauge (902) is fixedly installed on the outer wall of the high-pressure storage tank (9), and an air inlet end of the pressure gauge (902) is connected to the inside of the high-pressure storage tank (9).

6. The tail gas recovery device for preparing dry ice according to claim 1, characterized in that: A cold water tank (16) is fixedly mounted on the top of the support frame (10), the connecting pipe (7) passes through the cold water tank (16), and a liquid injection pipe (1601) is provided at the top of the cold water tank (16).

7. The exhaust gas recovery device for preparing dry ice according to claim 6, characterized in that: A temperature sensor (17) is fixedly mounted on the top of the cold water tank (16), and a detection end of the temperature sensor (17) extends into the cold water tank (16). A hose (18) is connected to the back of the cold water tank (16), and a nozzle (19) is connected to the rear end of the hose (18).

8. The exhaust gas recovery device for preparing dry ice according to claim 1, characterized in that: A dry ice maker (14) is arranged at the rear of the compressor (12); an air inlet end of the dry ice maker (14) is connected to an air outlet end of the compressor (12) via a pipeline; a discharge pipe (1401) is arranged at the top of the dry ice maker (14); a dry ice collector (15) is arranged at the rear of the dry ice maker (14); and the discharge pipe (1401) extends into the dry ice collector (15).

9. The exhaust gas recovery device for preparing dry ice according to claim 1, characterized in that: The connecting pipe (7) comprises a front end pipe (701) and a rear end pipe (702); a secondary separation box (20) is provided between the front end pipe (701) and the rear end pipe (702); the secondary separation box (20) is located in the cold water tank (16); a selective permeable membrane (21) is fixedly installed inside the secondary separation box (20); an air outlet pipe (22) is provided at the front and back ends of the secondary separation box (20); an end of the air outlet pipe (22) away from the secondary separation box (20) extends out from the cold water tank (16).

10. The exhaust gas recovery device for preparing dry ice according to claim 9, characterized in that: The selective permeable membrane (21) is a polyimide membrane. The selective permeable membrane (21) is tapered, and the smaller end of the selective permeable membrane (21) faces the rear end tube (702).

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