Method for capturing carbon dioxide

Abstract

The present application relates to the technical field of carbon dioxide capture, and discloses a carbon dioxide capture method, which comprises the following steps: (1) contacting raw gas with a perfluorinated solvent under a pressure of 2-7 MPa to perform absorption, so as to obtain purified gas G i and absorption liquid X containing carbon dioxide and nitrogen i ; optionally, the absorption liquid X i is at least divided into A i and B i parts, wherein the A i part is returned to step (1) to be added into the raw gas; the absorption liquid X i or the B i part is subjected to desorption, so as to obtain regenerated perfluorinated solvent Z i and desorption gas J containing carbon dioxide and nitrogen i ; (2) judging the carbon dioxide concentration in the desorption gas J i , when the carbon dioxide concentration in the desorption gas J i is less than 90 wt%, the desorption gas J i is used as the raw gas, and the step (1) is repeated. The method in the present application uses the perfluorinated solvent as the carbon dioxide absorbent, and can reduce the energy consumption of regeneration by pressure reduction, and is suitable for industrial popularization.

Description

Technical Field

[0001] This invention relates to the field of carbon dioxide capture technology, and more specifically to a method for capturing carbon dioxide. Background Technology

[0002] Among numerous flue gas CO2 capture technologies, carbon capture processes using organic amines as absorbents are currently the most mature and widely used in industrial applications. MEA (ethanolamine) as an absorbent boasts advantages such as high absorption efficiency, low cost, recyclability, and high product purity, achieving a decarbonization efficiency of up to 90%. However, the chemical absorption method of MEA has excessively high energy consumption, with absorbent regeneration accounting for approximately 70% of the total system energy consumption. Furthermore, MEA absorbents suffer significant losses due to oxidation and degradation during operation. According to analysis results from the Norwegian TCM carbon capture test, up to 1.5 kg of MEA is lost for every 1 ton of CO2 captured. Therefore, research into novel absorbents is attracting increasing attention.

[0003] Perfluorinated solvents are a new type of green solvent that can dissolve large amounts of carbon dioxide, making them suitable for carbon dioxide capture. However, perfluorinated solvents also have some solubility for nitrogen, so directly using them to capture carbon dioxide from flue gas cannot yield high-purity carbon dioxide. Furthermore, perfluorinated solvents are volatile, leading to significant losses. Summary of the Invention

[0004] The purpose of this invention is to solve the problems of low carbon dioxide purity and high loss when using perfluorinated solvents to capture carbon dioxide in the prior art, and to provide a carbon dioxide capture method that has the advantages of low regeneration energy consumption, strong carbon dioxide absorption capacity, low loss and high carbon dioxide purity.

[0005] To achieve the above objectives, the present invention provides a carbon dioxide capture method, the method comprising the following steps:

[0006] (1) The raw gas is contacted with a perfluorinated solvent at 2-7 MPa for absorption to obtain purified gas G. i And absorbent liquid X containing carbon dioxide and nitrogen i ;

[0007] Optionally, the absorbent liquid X i At least divided into A i Part and B i Part, wherein, the A i Partial return step (1) involves adding the raw material gas;

[0008] The absorbent liquid X i Or the aforementioned B i Partial desorption yields regenerated perfluorinated solvent Z.i And desorbed gas containing carbon dioxide and nitrogen J i ;

[0009] (2) Determine the desorption gas J i The carbon dioxide concentration in the desorbed gas J i When the carbon dioxide concentration in the gas is <90wt%, the desorbed gas J i As the feed gas, repeat step (1); when the desorbed gas J i When the carbon dioxide concentration in the solution is ≥90wt%, the repeated operation is stopped; where i is the number of operations in step (1);

[0010] (3) After stopping the repeated operation, optionally remove the desorbed gas J i It is liquefied to obtain liquefied carbon dioxide.

[0011] The technical effects that can be achieved by the present invention through the above technical solution are as follows:

[0012] 1) The carbon dioxide capture method provided in this invention uses a perfluorinated solvent as a carbon dioxide absorbent and reduces regeneration energy consumption through depressurization regeneration.

[0013] 2) The carbon dioxide capture method provided in this invention utilizes the difference in the absorption capacity of perfluorinated solvents for carbon dioxide and nitrogen under high pressure. By repeatedly performing absorption-desorption operations on the desorbed gas, high-purity liquefied carbon dioxide can be obtained.

[0014] 3) The carbon dioxide capture method provided in this invention can avoid the volatilization of perfluorinated solvents and minimize the volatilization of perfluorinated solvents by adding silicone oil and setting a two-stage condenser;

[0015] 4) The carbon dioxide capture method provided in this invention can separate a portion of high-purity carbon dioxide from flue gas, which is suitable for industrial application. Detailed Implementation

[0016] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0017] This invention provides a method for capturing carbon dioxide, the method comprising the following steps:

[0018] (1) The raw gas is contacted with a perfluorinated solvent at 2-7 MPa for absorption to obtain purified gas G. iAnd absorbent liquid X containing carbon dioxide and nitrogen i ;

[0019] Optionally, the absorbent liquid X i At least divided into A i Part and B i Part, wherein, the A i Partial return step (1) involves adding the raw material gas;

[0020] The absorbent liquid X i Or the aforementioned B i Partial desorption yields regenerated perfluorinated solvent Z. i And desorbed gas containing carbon dioxide and nitrogen J i ;

[0021] (2) Determine the desorption gas J i The carbon dioxide concentration in the desorbed gas J i When the carbon dioxide concentration in the gas is <90wt%, the desorbed gas J i As the feed gas, repeat step (1); when the desorbed gas J i When the carbon dioxide concentration in the solution is ≥90wt%, the repeated operation is stopped; where i is the number of operations in step (1);

[0022] (3) After stopping the repeated operation, optionally remove the desorbed gas J i It is liquefied to obtain liquefied carbon dioxide.

[0023] In this invention, the perfluorinated solution has different absorption capacities for carbon dioxide and nitrogen under high pressure. By repeatedly absorbing and desorbing the desorbed gas containing carbon dioxide and nitrogen, the nitrogen in the desorbed gas can be gradually separated by utilizing the difference in absorption capacity of the perfluorinated solution for carbon dioxide and nitrogen, thus obtaining high-purity carbon dioxide.

[0024] In a preferred embodiment, the feed gas contains carbon dioxide and nitrogen, and is preferably flue gas. However, this invention does not specifically limit the type of flue gas; common flue gases used in carbon dioxide capture can be used, such as power plant flue gas or refinery waste gas.

[0025] In a preferred embodiment, the feed pressure of the raw material gas is 2-7 MPa, preferably 2.5-4 MPa; the feed temperature of the raw material gas is 10-60°C, preferably 25-40°C. In this invention, the raw material gas is compressed using a compressor before being brought into contact with the perfluorinated solvent under high pressure.

[0026] In a preferred embodiment, the perfluorinated solvent has a molecular weight of 200-500 g / mol, a viscosity of 0.4-0.6 mPa·s at 20°C, and a density of 1-1.8 g / cm³. 3 The boiling point is 40-100℃. The density and boiling point of the perfluorinated solvent are measured at room temperature and pressure.

[0027] In a preferred embodiment, the perfluorinated solvent is selected from one or more of perfluorohexanone, perfluorohexane, perfluoroheptanone, perfluorooctanone, and perfluorooctane.

[0028] In a preferred embodiment, the volume ratio of the raw material gas to the perfluorinated solvent is 1-30:1, preferably 5-15:1.

[0029] In a preferred embodiment, the contact is carried out at 2.5-4 MPa and the contact temperature is 10-60°C, preferably 25-40°C.

[0030] In a preferred embodiment, the absorption is carried out in an adsorption tower; wherein the feed gas is fed from the bottom of the adsorption tower, the perfluorinated solvent is fed from the top of the adsorption tower, the feed gas and the perfluorinated solvent are contacted countercurrently, and part of the carbon dioxide and part of the nitrogen in the feed gas are absorbed by the perfluorinated solvent, and an absorbent liquid X containing carbon dioxide and nitrogen can be collected from the bottom of the adsorption tower. i The remaining raw material gas is purified gas G. i It is extracted from the top of the absorption tower.

[0031] In a preferred embodiment, when the absorbent X i When the carbon dioxide concentration in the absorbent is 40-80 wt%, the absorbent X i At least divided into A i Part and B i Part, wherein, the A i Partial return to step (1) as raw material gas, wherein B i Partially sent for desorption; the A i Partially accounting for the absorbent liquid X i 30-60% of the total mass, preferably 40-50%.

[0032] In this invention, by adjusting the absorbent liquid X i Diverting the flow can further reduce the overall energy consumption of carbon dioxide capture methods and reduce the number of repetitive operations.

[0033] In a preferred embodiment, the absorbent liquid X iThe feed pressure for desorption is 2-7 MPa, preferably 2.5-4 MPa; the feed temperature is 10-60℃, preferably 20-40℃. In this invention, a heat exchanger can be used to adjust the absorbent X. i The feed temperature of the absorbent liquid X i The feed pressure and feed temperature during desorption are preferably the same as those of the flue gas.

[0034] In a preferred embodiment, the desorption operating conditions include: a desorption temperature of 5-50°C, preferably 10-20°C; and a desorption pressure of 0.1-2 MPa, preferably 0.1-0.5 MPa.

[0035] In this invention, a perfluorinated solvent is used as a carbon dioxide absorbent, which can be desorbed by reducing pressure and thus reducing regeneration energy consumption.

[0036] In a preferred embodiment, the desorption is carried out in a desorption tower; wherein the bottom of the desorption tower contains silicone oil, and the silicone oil is the absorbent X that enters the desorption tower. i The total mass of the perfluorinated solvent contained in it is 0.5-3%; a two-stage condenser is provided at the top of the analytical column.

[0037] In this invention, by adding silicone oil to the bottom of the tower and setting up a two-stage condenser, the volatilization of perfluorinated solvents can be avoided and the volatilization of perfluorinated solvents can be minimized.

[0038] In a preferred embodiment, the regenerated perfluorinated solvent Z i Return to the source for repeated use.

[0039] In a preferred embodiment, the present invention does not specifically limit the number of repetitions, and can adjust them according to the content of carbon dioxide and nitrogen in the raw material gas. Preferably, i is 1-5, more preferably 2-4.

[0040] In a preferred embodiment, the method includes (3) after stopping the repeated operation, removing the desorbed gas J i It is liquefied to obtain liquefied carbon dioxide.

[0041] In this invention, by desorbing gas J i Liquefaction can separate a portion of high-purity carbon dioxide from the flue gas, thereby reducing carbon dioxide emissions.

[0042] The present invention will be described in detail below through embodiments. In these embodiments, the silicone oil added to the stripping tower accounts for a proportion of the absorbent liquid X fed into the stripping tower. i The total mass of the perfluorinated solvent is 1 wt%, and a two-stage condenser is installed at the top of the stripping column. The flue gas is simulated flue gas, consisting of 85 wt% N2 and 15 wt% CO2.

[0043] Example 1

[0044] (1) The raw material gas is flue gas. After being compressed in the compressor, the flue gas enters the absorption tower from the bottom of the absorption tower. Perfluorohexanone enters the absorption tower from the top of the absorption tower. The raw material gas and perfluorohexanone are absorbed in countercurrent contact at 3MPa and 30℃. The absorbent liquid X1 containing carbon dioxide and nitrogen is collected from the bottom of the absorption tower, and the purified gas G1 is collected from the top of the absorption tower. The feed pressure of the flue gas is 3MPa, the feed temperature is 30℃, the volume ratio of raw material gas to perfluorosolvent is 10:1, and the carbon dioxide concentration in absorbent liquid X1 is 50wt%.

[0045] The absorbent X1 is divided into part A1 and part B1. Part A1 accounts for 50% of the total mass of absorbent X1. Part A1 is returned to step (1) and mixed with flue gas to be used as raw gas. Part B1 is sent to the desorption tower for desorption. The desorption temperature is 20℃ and the desorption pressure is 0.1MPa. Desorbed gas J1 is collected from the top of the desorption tower and regenerated perfluorohexanone Z1 is collected from the bottom of the desorption tower. The collected regenerated perfluorohexanone Z1 is returned to the absorber tower for reuse.

[0046] (2) The carbon dioxide concentration in the desorbed gas J1 is 80wt%. Repeat step (1): the desorbed gas J1 is contacted countercurrently with perfluorohexanone for absorption to obtain an absorbent liquid X2 containing carbon dioxide and nitrogen and a purified gas G2.

[0047] The carbon dioxide concentration in absorbent X2 is 80 wt%. Absorbent X2 is divided into part A2 and part B2. Part A2 accounts for 40% of the total mass of absorbent X2. Part A2 is returned to step (1) and mixed with desorbed gas J1 to be used as raw gas. Part B2 is sent to the desorption tower for desorption to obtain desorbed gas J2 containing carbon dioxide and nitrogen and regenerated perfluorinated solvent Z2. Among them, the collected regenerated perfluorohexanone Z2 is returned to the absorption tower for reuse.

[0048] (3) The carbon dioxide concentration in the desorbed gas J2 is 91 wt%. Stop the repeated operation and liquefy the obtained desorbed gas J2 to obtain liquefied carbon dioxide with a purity of 99.9%. The total loss of perfluorinated solvent used in the whole process is calculated to be 4%.

[0049] Example 2

[0050] (1) The raw material gas is flue gas. After being compressed in the compressor, the flue gas enters the absorption tower from the bottom of the absorption tower. Perfluorohexanone enters the absorption tower from the top of the absorption tower. The raw material gas and perfluorohexanone are absorbed in countercurrent contact at 3MPa and 30℃. The absorbent liquid X1 containing carbon dioxide and nitrogen is collected from the bottom of the absorption tower, and the purified gas G1 is collected from the top of the absorption tower. The feed pressure of the flue gas is 3MPa, the feed temperature is 30℃, the volume ratio of raw material gas to perfluorosolvent is 10:1, and the carbon dioxide concentration in absorbent liquid X1 is 50wt%.

[0051] The absorbent X1 is sent to the desorption tower for desorption at a temperature of 10°C and a pressure of 0.1 MPa. The desorbed gas J1 is collected from the top of the desorption tower, and the regenerated perfluorohexanone Z1 is collected from the bottom of the desorption tower. The collected regenerated perfluorohexanone Z1 is returned to the absorption tower for reuse.

[0052] (2) The carbon dioxide concentration in the desorbed gas J1 is 50wt%. Repeat step (1): the desorbed gas J1 is contacted countercurrently with perfluorohexanone for absorption to obtain an absorbent liquid X2 containing carbon dioxide and nitrogen and a purified gas G2.

[0053] The carbon dioxide concentration in absorbent X2 is 80 wt%. All of absorbent X2 is sent to the desorption tower for desorption to obtain desorbed gas J2 containing carbon dioxide and nitrogen and regenerated perfluorinated solvent Z2. Among them, the collected regenerated perfluorohexanone Z2 is returned to the absorbent tower for reuse.

[0054] The carbon dioxide concentration in the desorbed gas J2 is 80 wt%. Step (1) is repeated again: the desorbed gas J2 is contacted countercurrently with perfluorohexanone for absorption to obtain an absorbent liquid X3 containing carbon dioxide and nitrogen and a purified gas G3.

[0055] The carbon dioxide concentration in absorbent X3 is 90 wt%. All of absorbent X3 is sent to the desorption tower for desorption to obtain desorbed gas J3 containing carbon dioxide and nitrogen and regenerated perfluorinated solvent Z3. Among them, the collected regenerated perfluorohexanone Z3 is returned to the absorbent tower for reuse.

[0056] (3) The desorbed gas J3 carbon dioxide is 90 wt%. Stop the repeated operation and liquefy the obtained desorbed gas J3 to obtain liquefied carbon dioxide with a purity of 99.9%. The total loss of perfluorinated solvent used in the whole process is calculated to be 5%.

[0057] Comparative Example 1

[0058] Similar to Example 1, except that no silicone oil is added to the stripping tower, and the total loss of perfluorinated solvent used in the entire process is calculated to be 10%.

[0059] As can be seen from Examples 1 and 2, the carbon dioxide capture method provided in this invention utilizes the difference in the absorption capacity of perfluorinated solvents for carbon dioxide and nitrogen under high pressure, and obtains high-purity liquefied carbon dioxide by repeatedly performing absorption-desorption operations on the desorbed gas.

[0060] By comparing Example 1 and Example 2, it can be seen that by adjusting the absorbent X... i Diverting the flow can reduce the number of repetitive operations and further reduce the overall energy consumption of carbon dioxide capture methods.

[0061] By comparing Example 1 and Comparative Example 1, it can be seen that the carbon dioxide capture method provided in this invention can avoid the volatilization of perfluorinated solvents by adding silicone oil, thereby minimizing the volatilization of perfluorinated solvents and reducing the loss of perfluorinated solvents.

[0062] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for capturing carbon dioxide, characterized in that, The method includes the following steps: (1) The raw gas is contacted with the perfluorinated solvent at 10-60°C and 2-7 MPa to absorb, and the purified gas G is obtained i and the absorption liquid X containing carbon dioxide and nitrogen i ; Optionally, the absorption liquid X is added to the raw gas in step (1) i divided into at least A i and B i wherein the A i portion is returned to step (1) to add the raw gas desorbing the absorption liquid X i or the B i part to obtain a regenerated perfluorinated solvent Z i and a desorption gas J containing carbon dioxide and nitrogen i ; during the desorption process, silicone oil is present; (2) determining the carbon dioxide concentration in desorption gas J i When the carbon dioxide concentration in desorption gas J i is < 90 wt%, the desorption gas J i is used as raw material gas, and the step (1) is repeated; when the carbon dioxide concentration in desorption gas J i is ≥ 90 wt%, the repeating operation is stopped; wherein i is the number of operations of the step (1). (3) after the repetition operation is stopped, optionally, the desorption gas J i is liquefied to obtain liquefied carbon dioxide.

2. The method according to claim 1, wherein, The raw material gas contains carbon dioxide and nitrogen; And / or, the feed pressure of the raw material gas is 2-7 MPa; the feed temperature of the raw material gas is 10-60℃.

3. The method according to claim 2, wherein, The raw material gas is power plant flue gas or refinery waste gas; And / or, the feed pressure of the raw material gas is 2.5-4 MPa; the feed temperature of the raw material gas is 25-40℃.

4. The method according to any one of claims 1-3, wherein, The perfluorinated solvent has a molecular weight of 200-500 g / mol, a viscosity of 0.4-0.6 mPa-s at 20°C, a density of 1-1.8 g / cm 3 , and a boiling point of 40-120°C.

5. The method according to any one of claims 1-3, wherein, The perfluorinated solvent is selected from one or more of perfluorohexanone, perfluorohexane, perfluoroheptanone, perfluorooctanone, and perfluorooctane.

6. The method according to claim 4, wherein, The perfluorinated solvent is selected from one or more of perfluorohexanone, perfluorohexane, perfluoroheptanone, perfluorooctanone, and perfluorooctane.

7. The method according to any one of claims 1-3 and 6, wherein, The volume ratio of the raw material gas to the perfluorinated solvent is 1-30:1; And / or, the contact is carried out at 2.5-4 MPa and the contact temperature is 25-40°C.

8. The method according to claim 7, wherein, The volume ratio of the raw material gas to the perfluorinated solvent is 5-15:

1.

9. The method according to claim 5, wherein, The volume ratio of the raw material gas to the perfluorinated solvent is 1-30:1; And / or, the contact is carried out at 2.5-4 MPa and the contact temperature is 25-40°C.

10. The method according to claim 9, wherein, The volume ratio of the raw material gas to the perfluorinated solvent is 5-15:

1.

11. The method according to any one of claims 1-3, 6, 8-10, wherein, When the carbon dioxide concentration in the absorption liquid X i is 40-80 wt%, the absorption liquid X i is divided into at least two parts A i and B i , wherein the A i part accounts for 30-60% of the total mass of the absorption liquid X i .

12. The method according to claim 11, wherein, When the carbon dioxide concentration in the absorption liquid X i is 40-80 wt%, the absorption liquid X i is divided into at least two parts A i and B i , wherein the A i part accounts for 40-50% of the total mass of the absorption liquid X i .

13. The method according to claim 4, wherein, When the carbon dioxide concentration in the absorption liquid X i is 40-80 wt%, the absorption liquid X i is divided into at least two parts A i and B i , wherein the A i part accounts for 30-60% of the total mass of the absorption liquid X i .

14. The method according to claim 13, wherein, When the carbon dioxide concentration in the absorption liquid X i is 40-80 wt%, the absorption liquid X i is divided into at least two parts A i and B i , wherein the A i part accounts for 40-50% of the total mass of the absorption liquid X i .

15. The method according to claim 5, wherein, When the carbon dioxide concentration in the absorption liquid X i is 40-80 wt%, the absorption liquid X i is divided into at least i a first part A i and a second part B i , wherein the first part A i comprises 30-60% of the total mass of the absorption liquid X.

16. The method according to claim 15, wherein, When the absorbent X i When the carbon dioxide concentration in the absorbent is 40-80 wt%, the absorbent X i At least divided into A i Part and B i Part, wherein, the A i Partially accounting for the absorbent liquid X i 40-50% of the total mass.

17. The method according to claim 7, wherein, When the absorbent X i When the carbon dioxide concentration in the absorbent is 40-80 wt%, the absorbent X i At least divided into A i Part and B i Part, wherein, the A i Partially accounting for the absorbent liquid X i 30-60% of the total mass.

18. The method according to claim 17, wherein, When the absorbent X i When the carbon dioxide concentration in the absorbent is 40-80 wt%, the absorbent X i At least divided into A i Part and B i Part, wherein, the A i Partially accounting for the absorbent liquid X i 40-50% of the total mass.

19. The method according to any one of claims 1-3, 6, 8-10, and 12-18, wherein, The desorption operating conditions include: a desorption temperature of 5-50℃ and a desorption pressure of 0.1-2MPa.

20. The method according to claim 19, wherein, The desorption temperature is 10-20℃; the desorption pressure is 0.1-0.5MPa.

21. The method according to claim 4, wherein, The desorption operating conditions include: a desorption temperature of 5-50℃ and a desorption pressure of 0.1-2MPa.

22. The method according to claim 21, wherein, The desorption temperature is 10-20℃; the desorption pressure is 0.1-0.5MPa.

23. The method according to claim 5, wherein, The desorption operating conditions include: a desorption temperature of 5-50℃ and a desorption pressure of 0.1-2MPa.

24. The method according to claim 23, wherein, The desorption temperature is 10-20℃; the desorption pressure is 0.1-0.5MPa.

25. The method according to claim 7, wherein, The desorption operating conditions include: a desorption temperature of 5-50℃ and a desorption pressure of 0.1-2MPa.

26. The method of claim 25, wherein, The desorption temperature is 10-20℃; the desorption pressure is 0.1-0.5MPa.

27. The method according to claim 11, wherein, The desorption operating conditions include: a desorption temperature of 5-50℃ and a desorption pressure of 0.1-2MPa.

28. The method according to claim 27, wherein, The desorption temperature is 10-20℃; the desorption pressure is 0.1-0.5MPa.

29. The method according to any one of claims 1-3, 6, 8-10, 12-18, and 20-28, wherein, The desorption is carried out in a desorption tower; wherein the bottom of the desorption tower contains silicone oil, and a two-stage condenser is provided at the top of the desorption tower.

30. The method according to claim 4, wherein, The desorption is carried out in a desorption tower; wherein the bottom of the desorption tower contains silicone oil, and a two-stage condenser is provided at the top of the desorption tower.

31. The method according to claim 5, wherein, The desorption is carried out in a desorption tower; wherein the bottom of the desorption tower contains silicone oil, and a two-stage condenser is provided at the top of the desorption tower.

32. The method according to claim 7, wherein, The desorption is carried out in a desorption tower; wherein the bottom of the desorption tower contains silicone oil, and a two-stage condenser is provided at the top of the desorption tower.

33. The method according to claim 11, wherein, The desorption is carried out in a desorption tower; wherein the bottom of the desorption tower contains silicone oil, and a two-stage condenser is provided at the top of the desorption tower.

34. The method according to claim 19, wherein, The desorption is carried out in a desorption tower; wherein the bottom of the desorption tower contains silicone oil, and a two-stage condenser is provided at the top of the desorption tower.

35. The method according to any one of claims 1-3, 6, 8-10, 12-18, 20-28, and 30-34, wherein, The regenerated perfluorinated solvent Z i Return to the source for repeated use.

36. The method according to claim 4, wherein, The regenerated perfluorinated solvent Z i Return to the source for repeated use.

37. The method according to claim 5, wherein, The regenerated perfluorinated solvent Z i Return to the source for repeated use.

38. The method according to claim 7, wherein, The regenerated perfluorinated solvent Z i Return to the source for repeated use.

39. The method according to claim 11, wherein, The regenerated perfluorinated solvent Z i Return to the source for repeated use.

40. The method of claim 19, wherein, The regenerated perfluorinated solvent Z i Return to the source for repeated use.

41. The method according to claim 29, wherein, The regenerated perfluorinated solvent Z i Return to the source for repeated use.

42. The method according to any one of claims 1-3, 6, 8-10, 12-18, 20-28, 30-34, and 36-41, wherein, The method includes (3) desorbing the gas J i The mixture is liquefied to obtain liquefied carbon dioxide.

43. The method according to claim 4, wherein, The method includes (3) desorbing the gas J i The mixture is liquefied to obtain liquefied carbon dioxide.

44. The method according to claim 5, wherein, The method includes (3) desorbing the gas J i The mixture is liquefied to obtain liquefied carbon dioxide.

45. The method according to claim 7, wherein, The method includes (3) desorbing the gas J i The mixture is liquefied to obtain liquefied carbon dioxide.

46. ​​The method according to claim 11, wherein, The method includes (3) desorbing the gas J i The mixture is liquefied to obtain liquefied carbon dioxide.

47. The method according to claim 19, wherein, The method includes (3) desorbing the gas J i The mixture is liquefied to obtain liquefied carbon dioxide.

48. The method according to claim 29, wherein, The method includes (3) desorbing the gas J i The mixture is liquefied to obtain liquefied carbon dioxide.

49. The method according to claim 35, wherein, The method includes (3) desorbing the gas J i The mixture is liquefied to obtain liquefied carbon dioxide.