A continuous separation device for C4F7N / CO2 mixed gas and a method for measuring the separation and recovery of C4F7N.

Abstract

A kind of C4F7N / CO2 Mixed gas continuous separation device and C4F7N separation recovery quantity metering method, belong to electrical equipment insulation gas field, solve the problems of low separation purification efficiency, high cost and unable to accurately measure the quantity of separated and recovered C4F7N gas of existing C4F7N / CO2 Separation recovery device, the device of the present application is by circulating air, cryogenic liquefaction, residual backflow, re-into, using impurity adsorption, C4F7N / CO2 Mixed gas mixing ratio detection, C4F7N gas and CO2 Gas cryogenic separation in cryogenic liquefaction separation tank, CO2 Adsorption tower desorption regeneration, calculate the quantity of liquid C4F7N separated in cryogenic liquefaction separation tank, improve the efficiency of separation and purification, while accurately measure the quantity of C4F7N separation recovery, avoid using metering device manual directly take the mass of liquefied C4F7N exists C4F7N mass measurement inaccurate problem.

Description

Technical Field

[0001] This invention belongs to the field of insulating gas technology for electrical equipment, and relates to a continuous separation device for C4F7N / CO2 mixed gas and a method for measuring the amount of C4F7N separated and recovered. Background Technology

[0002] SF6 gas is used in electrical equipment as an insulation and arc-quenching medium; however, SF6 is a strong greenhouse gas. In recent years, C4F7N / CO2 mixed gas has gained widespread popularity in the electrical field, and some substations have already installed C4F7N / CO2 mixed gas electrical equipment. However, since C4F7N / CO2 mixed gas electrical equipment is relatively new, the relevant operation and maintenance technologies are not yet fully developed.

[0003] Separation and purification have always been key aspects of mixed gas operation and maintenance. Currently, commonly used techniques include cryogenic separation, membrane separation, and adsorbent adsorption. Since C4F7N / CO2 mixtures typically contain no more than 10% C4F7N, and its liquefaction temperature is similar to that of CO2 (which accounts for over 90%), cryogenic separation methods, based on the difference in liquefaction temperatures between different gas components, are not suitable for the separation and purification of C4F7N / CO2 mixtures. Furthermore, related research indicates that C4F7N can cause permanent and irreversible damage to polymer membranes; therefore, membrane separation methods are also unsuitable for the separation and purification of this mixture. As for adsorbent adsorption, due to the limited quantity of adsorbent, it is difficult to adsorb large amounts of gas; therefore, it is generally used for the purification of trace impurities in gas separation and purification processes. In addition, regulations require maintenance personnel to measure the amount of C4F7N gas recovered. Currently, this is mainly done by weighing the recovered C4F7N gas, which is complex, prone to errors, and difficult to manage on-site.

[0004] Existing separation and purification methods are insufficient for effectively separating C4F7N / CO2 mixed gases, resulting in low gas recovery and reuse rates. Furthermore, the high price of C4F7N gas (generally not less than 5,000 yuan / kg) leads to high operation and maintenance costs for power systems. Therefore, there is an urgent need to improve the separation and purification efficiency of C4F7N / CO2 mixed gases, reduce economic costs, and automatically and accurately measure the amount of C4F7N gas recovered. Summary of the Invention

[0005] This invention addresses the problems of low separation and purification efficiency, high cost, and inability to accurately measure the amount of C4F7N gas separated and recovered in existing C4F7N / CO2 separation and recovery devices.

[0006] The present invention solves the above-mentioned technical problems through the following technical solutions: A C4F7N / CO2 mixed gas continuous separation device includes: an inlet (1), a first solenoid valve (2), an impurity adsorption tower (3), a first compressor (4), a pressure sensor (5), a temperature sensor (6), a cryogenic liquefaction separation tank (7), a second solenoid valve (8), a third solenoid valve (9), a liquid pump (10), a filling port (11), a proportional valve (12), a mixing ratio detection module (13), a fourth solenoid valve (14), a first CO2 adsorption tower (15), a first heating module (16), a fifth solenoid valve (17), a sixth solenoid valve (18), a seventh solenoid valve (19), a second CO2 adsorption tower (20), a second heating module (21), an eighth solenoid valve (22), a ninth solenoid valve (23), a vacuum gauge (24), a vacuum compressor (25), and a vacuum discharge port (26). The input end of the first solenoid valve (2) serves as the air inlet (1) of the device. The output end of the first solenoid valve (2) is sealed to the input end of the impurity adsorption tower (3) through a pipe. The output end of the impurity adsorption tower (3) is sealed to the input end of the first compressor (4) through a pipe. The output end of the first compressor (4) is sealed to the input end of the cryogenic liquefaction separator (7) through a pipe. The pressure sensor (5) and temperature sensor (6) are respectively installed on the cryogenic liquefaction separator (7) to detect the pressure and temperature of the cryogenic liquefaction separator (7). The first output end of the cryogenic liquefaction separator (7) is sealed to the input end of the second solenoid valve (8) through a pipe. The second output end of the cryogenic liquefaction separator (7) is sealed to the input end of the third solenoid valve (9). The inlet is sealed by a pipe. The output end of the third solenoid valve (9) is sealed by a pipe to the input end of the liquid pump (10). The output end of the liquid pump (10) serves as the filling port (11). The output end of the second solenoid valve (8) is sealed by a pipe to the input end of the seventh solenoid valve (19). The output end of the seventh solenoid valve (19) is sealed by a pipe to the input end of the eighth solenoid valve (22). The output end of the eighth solenoid valve (22) is sealed by a pipe to the input end of the vacuum compressor (25). The output end of the vacuum compressor (25) serves as the vacuum discharge port (26). The input end of the proportional valve (12) is connected by a pipe to the input end of the first compressor (4). The output end of the proportional valve (12) and the mixing ratio detection module (1) are connected by a pipe to the input end of the first compressor (4). The input end of the third solenoid valve (3) and the output end of the second solenoid valve (8) are sealed together by a three-way pipe. The output end of the mixing ratio detection module (13) is sealed together by a pipe between the output end of the second solenoid valve (8) and the input end of the seventh solenoid valve (19). The input end of the fourth solenoid valve (14) is sealed together by a pipe between the output end of the second solenoid valve (8) and the input end of the seventh solenoid valve (19). The output end of the fourth solenoid valve (14), the input end of the first CO2 adsorption tower (15), and the input end of the fifth solenoid valve (17) are sealed together by a three-way pipe. The output end of the first CO2 adsorption tower (15) and the input end of the sixth solenoid valve (18) are sealed together by a pipe. The output end of the fifth solenoid valve (17) is sealed together by a three-way pipe. The output end of the second CO2 adsorption tower (20) is sealed and connected to the pipeline between the output end of the eighth solenoid valve (22) and the input end of the vacuum compressor (25) via a pipeline. The input end of the second CO2 adsorption tower (20) is sealed and connected to the pipeline between the output end of the seventh solenoid valve (19) and the input end of the eighth solenoid valve (22) via a pipeline. The output end of the second CO2 adsorption tower (20) is sealed and connected to the input end of the ninth solenoid valve (23) via a pipeline. The output end of the sixth solenoid valve (18) is sealed and connected to the output end of the ninth solenoid valve (23) via a pipeline, and then sealed and connected to the output end of the impurity adsorption tower (3) via a pipeline. The vacuum gauge (24) is sealed and installed on the pipeline between the output end of the eighth solenoid valve (22) and the input end of the vacuum compressor (25).The first heating module (16) and the second heating module (21) are respectively installed on the outer walls of the first CO2 adsorption tower (15) and the second CO2 adsorption tower (20), and are used to heat or cool the first CO2 adsorption tower (15) and the second CO2 adsorption tower (20).

[0007] Furthermore, the working process of the device is as follows: S1. The C4F7N / CO2 mixed gas to be separated and purified enters through the inlet (1). The first solenoid valve (2) is opened, and the C4F7N / CO2 mixed gas to be separated and purified enters the impurity adsorption tower (3) for impurity adsorption. The proportional valve (12) is opened, and the C4F7N / CO2 mixed gas to be separated and purified after removing impurities is input into the mixing ratio detection module (13). The proportion of C4F7N in the C4F7N / CO2 mixed gas is detected as follows: ; S2. Start the first compressor (4) and set the boost pressure to 3.0 MPa. Pressurize the C4F7N / CO2 mixed gas (after removing impurities) and input it into the cryogenic liquefaction separator (7). Set the temperature of the cryogenic liquefaction separator (7) to -5℃ to liquefy the C4F7N gas. At this time, open the second solenoid valve (8) and the fourth solenoid valve (14). The mixing ratio detection module (13) detects the proportion of C4F7N gas in the mixed gas before the nth start-up of the liquid injection. After detection, the mixed gas flows to the CO2 adsorption tower; S3. After detection, close the second solenoid valve (8), then open the third solenoid valve (9) and start the liquid pump (10) to fill the cylinder with liquid C4F7N. After the liquid filling is completed, close the third solenoid valve (9) and the liquid pump (10). S4. Open the second solenoid valve (8) and the solenoid valve of the gas path of the first CO2 adsorption tower, and start the first compressor (4). The mixed gas in the cryogenic liquefaction separation tank (7) enters the cryogenic liquefaction separation tank (7) again after passing through the first CO2 adsorption tower. During this process, the mixing ratio detection module (13) continuously detects the mixing ratio. Due to the adsorption effect, the amount of CO2 gas gradually decreases and the proportion of C4F7N gas gradually increases. When the proportion of C4F7N gas reaches 6%, close the fourth solenoid valve (14). After 1 minute, close the sixth solenoid valve (18) and the first compressor (4). At this time, open the second solenoid valve (8), use the mixing ratio detection module (13) to detect the proportion of C4F7N gas, and record the value after 1 minute. This is denoted as the percentage of C4F7N after the nth adsorption. S5, Detection and Acquisition Afterwards, close the second solenoid valve (8) and the mixing ratio detection module (13), start the first compressor (4), open the solenoid valve of the CO2 adsorption tower gas path, pump gas for 3 minutes, and pump all the gas in the CO2 adsorption tower and pipeline into the cryogenic liquefaction separator (7), and control the temperature of the cryogenic liquefaction separator (7) at -5℃, and record the pressure of the cryogenic liquefaction separator (7) at this time. , is the pressure of the cryogenic liquefaction separator (7) after the nth cryogenic separation; then the solenoid valve of the CO2 adsorption tower gas path is closed, the first solenoid valve (2) is opened to continue gas intake, and the next round of cryogenic separation operation is carried out.

[0008] A method for measuring the amount of C4F7N separated and recovered in the above-mentioned continuous separation device for C4F7N / CO2 mixed gas includes the following steps: 1) Calculate the volume of CO2 in the cryogenic tank before the nth injection under standard conditions. Given that the effective volume of the cryogenic liquefaction separator (7) is V, and the mixing ratio detection module (13) detects that the proportion of C4F7N before liquid injection is... After adsorption by the liquid, the proportion of C4F7N was 10%. Cryogenic liquefaction separation tank before liquid injection (7) The pressure is constant at 3.0 MPa. According to Dalton's law of partial pressures, the partial pressure of C4F7N gas before liquid injection in the cryogenic liquefaction separator (7) can be obtained. and CO2 gas partial pressure They are respectively: (1) (2) Since the volume of liquid C4F7N is extremely small and negligible, CO2 gas can be considered an ideal gas, according to the ideal gas law. (R is a constant), convert CO2 gas to its standard volume under the same molar amounts. for: (3) 2) Calculate the standard volume of C4F7N after the nth adsorption. First, calculate the partial pressure of C4F7N after the liquid is adsorbed by the CO2 adsorption tower and enters the cryogenic liquefaction separation tank (7). and CO2 gas partial pressure They are respectively: (4) (5) Calculate the volume under standard conditions. for: (6) The standard volume of C4F7N in the gas after the nth liquid adsorption is: (7) 3) Calculate the total standard gas volume in the cryogenic liquefaction separator (7) during the nth cryogenic separation. ; Given that the total intake gas includes the gas after the (n-1)th liquid adsorption and the newly introduced gas, let the standard volume of the newly introduced gas in the nth cryogenic separation be... Let the standard volume of the total C4F7N gas in the cryogenic tank before the nth liquid injection be . The total standard volume of CO2 gas is The newly introduced mixed gas has a mixing ratio based on the initial mixing ratio detected in the first test. calculate: (8) Sorted as: (9) The total standard volume of C4F7N gas before the nth separation is: (10) 4) Calculate the mass of recovered C4F7N Calculate the standard volume of C4F7N recovered in the nth separation. for: (11) The density of C4F7N gas under standard conditions is known to be 8.298 kg / m³. 3 Therefore, the mass of C4F7N recovered in the nth separation is: (12) The total mass of C4F7N gas recovered is: (13) The total recovery rate was: (14) An electronic device includes a memory and a processor, the memory being used to store a program that supports the processor in executing the C4F7N separation and recovery measurement method described above, and the processor being configured to execute the program stored in the memory.

[0009] A storage medium storing a computer program, which, when executed by a processor, performs the steps of the C4F7N separation and recovery measurement method described above.

[0010] The advantages of this invention are: This invention improves separation and purification efficiency by employing a process of circulating air intake, cryogenic liquefaction, residual gas recirculation, and re-intake. It utilizes impurity adsorption, detection of the C4F7N / CO2 mixed gas ratio, cryogenic separation of C4F7N and CO2 gases in the cryogenic liquefaction separation tank, and desorption and regeneration of the CO2 adsorption tower. The amount of liquid C4F7N separated in the cryogenic liquefaction separation tank is calculated. Simultaneously, it accurately measures the amount of C4F7N separated and recovered, avoiding the inaccurate measurement of C4F7N mass caused by manually weighing the liquefied C4F7N using metering devices. This provides assistance for further purification of C4F7N. Attached Figure Description

[0011] Figure 1 This is a structural diagram of the C4F7N / CO2 mixed gas continuous separation device according to an embodiment of the present invention. Detailed Implementation

[0012] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0013] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments: I. Structure of the device like Figure 1 As shown, the C4F7N / CO2 mixed gas continuous separation device of the present invention includes: an air inlet (1), a first solenoid valve (2), an impurity adsorption tower (3), a first compressor (4), a pressure sensor (5), a temperature sensor (6), a cryogenic liquefaction separation tank (7), a second solenoid valve (8), a third solenoid valve (9), a liquid pump (10), a filling port (11), a proportional valve (12), a mixing ratio detection module (13), a fourth solenoid valve (14), a first CO2 adsorption tower (15), a first heating module (16), a fifth solenoid valve (17), a sixth solenoid valve (18), a seventh solenoid valve (19), a second CO2 adsorption tower (20), a second heating module (21), an eighth solenoid valve (22), a ninth solenoid valve (23), a vacuum gauge (24), a vacuum compressor (25), and a vacuum discharge port (26). The input end of the first solenoid valve (2) serves as the air inlet (1) of the device. The output end of the first solenoid valve (2) is sealed to the input end of the impurity adsorption tower (3) through a pipe. The output end of the impurity adsorption tower (3) is sealed to the input end of the first compressor (4) through a pipe. The output end of the first compressor (4) is sealed to the input end of the cryogenic liquefaction separator (7) through a pipe. The pressure sensor (5) and temperature sensor (6) are respectively installed on the cryogenic liquefaction separator (7) to detect the pressure and temperature of the cryogenic liquefaction separator (7). The first output end of the cryogenic liquefaction separator (7) is sealed to the input end of the second solenoid valve (8) through a pipe. The second output end of the cryogenic liquefaction separator (7) is sealed to the input end of the third solenoid valve (9). The inlet is sealed by a pipe. The output end of the third solenoid valve (9) is sealed by a pipe to the input end of the liquid pump (10). The output end of the liquid pump (10) serves as the filling port (11). The output end of the second solenoid valve (8) is sealed by a pipe to the input end of the seventh solenoid valve (19). The output end of the seventh solenoid valve (19) is sealed by a pipe to the input end of the eighth solenoid valve (22). The output end of the eighth solenoid valve (22) is sealed by a pipe to the input end of the vacuum compressor (25). The output end of the vacuum compressor (25) serves as the vacuum discharge port (26). The input end of the proportional valve (12) is connected by a pipe to the input end of the first compressor (4). The output end of the proportional valve (12) and the mixing ratio detection module (1) are connected by a pipe to the input end of the first compressor (4). The input end of the third solenoid valve (3) and the output end of the second solenoid valve (8) are sealed together by a three-way pipe. The output end of the mixing ratio detection module (13) is sealed together by a pipe between the output end of the second solenoid valve (8) and the input end of the seventh solenoid valve (19). The input end of the fourth solenoid valve (14) is sealed together by a pipe between the output end of the second solenoid valve (8) and the input end of the seventh solenoid valve (19). The output end of the fourth solenoid valve (14), the input end of the first CO2 adsorption tower (15), and the input end of the fifth solenoid valve (17) are sealed together by a three-way pipe. The output end of the first CO2 adsorption tower (15) and the input end of the sixth solenoid valve (18) are sealed together by a pipe. The output end of the fifth solenoid valve (17) is sealed together by a three-way pipe. The output end of the second CO2 adsorption tower (20) is sealed and connected to the pipeline between the output end of the eighth solenoid valve (22) and the input end of the vacuum compressor (25) via a pipeline. The input end of the second CO2 adsorption tower (20) is sealed and connected to the pipeline between the output end of the seventh solenoid valve (19) and the input end of the eighth solenoid valve (22) via a pipeline. The output end of the second CO2 adsorption tower (20) is sealed and connected to the input end of the ninth solenoid valve (23) via a pipeline. The output end of the sixth solenoid valve (18) is sealed and connected to the output end of the ninth solenoid valve (23) via a pipeline, and then sealed and connected to the output end of the impurity adsorption tower (3) via a pipeline. The vacuum gauge (24) is sealed and installed on the pipeline between the output end of the eighth solenoid valve (22) and the input end of the vacuum compressor (25).The first heating module (16) and the second heating module (21) are respectively installed on the outer walls of the first CO2 adsorption tower (15) and the second CO2 adsorption tower (20), and are used to heat or cool the first CO2 adsorption tower (15) and the second CO2 adsorption tower (20).

[0014] II. Operating Procedures of the Device (1) The C4F7N / CO2 mixed gas to be separated and purified enters through the inlet (1). The first solenoid valve (2) is opened, and the C4F7N / CO2 mixed gas to be separated and purified enters the impurity adsorption tower (3). The impurity adsorption tower (3) is filled with filters, desiccants, CF4 adsorbents, CO adsorbents, C3F8 adsorbents, etc., to adsorb impurities from the input C4F7N / CO2 mixed gas to be separated and purified. The proportional valve (12) is opened (the flow rate is adjusted to 300 mL / min), and the C4F7N / CO2 mixed gas to be separated and purified after removing impurities is input into the mixing ratio detection module (13). The proportion of C4F7N in the C4F7N / CO2 mixed gas is detected. .

[0015] (2) Based on the characteristics of the C4F7N / CO2 mixed gas, the higher the proportion of C4F7N gas in the C4F7N / CO2 mixed gas, the higher the liquefaction temperature of C4F7N gas. For example, at 3.0 MPa, the liquefaction temperatures of C4F7N gas with a proportion of 3% and CO2 gas with a proportion of 97% in the C4F7N / CO2 mixed gas are -7.43℃ and -7.03℃, respectively. The liquefaction temperatures of C4F7N gas with a proportion of 4% and CO2 gas with a proportion of 96% in the C4F7N / CO2 mixed gas are -0.62℃ and -7.4℃, respectively. Therefore, in this embodiment, the pressure is selected as 3.0 MPa and the liquefaction temperature is -5℃.

[0016] (3) Start the first compressor (4) Set the booster pressure to 3.0 MPa, pressurize the C4F7N / CO2 mixed gas (after removing impurities) and input it into the cryogenic liquefaction separator (7). Set the temperature of the cryogenic liquefaction separator (7) to -5℃ to liquefy the C4F7N gas. Most of the C4F7N gas in the cryogenic liquefaction separator (7) becomes liquid under low temperature and high pressure. At this time, open the second solenoid valve (8) and the fourth solenoid valve (14). At this time, the mixing ratio detection module (13) detects the proportion of C4F7N before the nth start of liquid injection. After detection, the gas flows to the first CO2 adsorption tower (15). (If the first CO2 adsorption tower (15) is in an activated state, the fourth solenoid valve (14) is closed and the seventh solenoid valve (19) is opened, and the gas flows to the second CO2 adsorption tower (20) after detection.)

[0017] (4) After detection, close the second solenoid valve (8), then open the third solenoid valve (9) and start the liquid pump (10) to fill the cylinder with liquid C4F7N; after the liquid pumping is completed, close the third solenoid valve (9) and the liquid pump (10) (since it is impossible to recover all the liquid C4F7N, the remaining liquid C4F7N will vaporize during the subsequent adsorption process), open the second solenoid valve (8), the fourth solenoid valve (14), and the sixth solenoid valve (18), and start the first compressor (4). The gas from the cryogenic liquefaction separator (7) passes through the first compressor. After passing through the CO2 adsorption tower (15), the CO2 gas enters the cryogenic liquefaction separation tank (7) again. During this process, the mixing ratio detection module (13) continuously detects the mixing ratio. Due to adsorption, the amount of CO2 gas gradually decreases, and the proportion of C4F7N gradually increases. When the proportion of C4F7N reaches 6%, the fourth solenoid valve (14) is closed. After 1 minute, the sixth solenoid valve (18) and the first compressor (4) are closed. At this time, the second solenoid valve (8) is opened, and the proportion of C4F7N is detected by the mixing ratio detection module (13). The value after 1 minute is recorded. Let it be denoted as the percentage of C4F7N after the nth adsorption.

[0018] (5) The first CO2 adsorption tower (15) and the second CO2 adsorption tower (20) serve as backups for each other and continuously adsorb CO2 gas. If the proportion of C4F7N is still less than 6% after 5 minutes, it indicates that the first CO2 adsorption tower (15) is saturated. At this time, the fourth solenoid valve (14) and the sixth solenoid valve (18) are closed, and the seventh solenoid valve (19) and the ninth solenoid valve (23) are opened. The second CO2 adsorption tower (20) is started to adsorb. At the same time, the fifth solenoid valve (17) is opened, the vacuum compressor (25) is turned on, and the first CO2 adsorption tower (15) is heated to 120°C through the first heating module (16) wrapped in the first CO2 adsorption tower (15). The adsorbent is heated and vacuumed to activate the first CO2 adsorption tower (15). The adsorbed CO2 is discharged from the vacuum outlet (26).

[0019] (6) Detection and acquisition Afterwards, close the second solenoid valve (8) and the mixing ratio detection module (13), start the first compressor (4), open the solenoid valve of the gas path where the CO2 adsorption tower is located (if the first CO2 adsorption tower (15) is used, then open the fourth solenoid valve (14) and the sixth solenoid valve (18); if the second CO2 adsorption tower (20) is used, then open the seventh solenoid valve (19) and the ninth solenoid valve (23)), evacuate the gas for 3 minutes, and evacuate all the gas in the CO2 adsorption tower and pipeline to the cryogenic liquefaction separator (7), and control the temperature of the cryogenic liquefaction separator (7) at -5℃, and record the pressure of the cryogenic liquefaction separator (7) at this time. , is the pressure of the cryogenic liquefaction separator (7) after the nth cryogenic separation. Then, the solenoid valve of the gas path where the CO2 adsorption tower is located is closed, and the first solenoid valve (2) is opened to continue gas intake for the next round of cryogenic separation. (Because the gas chamber mixing ratio does not change during the recovery process, there is no need to detect the mixing ratio of the incoming gas again; the initial mixing ratio is used.) calculate).

[0020] The C4F7N and CO2 are continuously separated and purified through the above steps to obtain C4F7N liquid. When the separation and purification work is completed, the small amount of mixed gas remaining in the cryogenic liquefaction separation tank (7) can be separated during the next separation and purification task.

[0021] III. Method for Measuring the Separation and Recovery of C4F7N 1) Calculate the CO2 volume in the cryogenic tank before the nth liquid injection (at 20℃ and 0.1MPa, hereinafter referred to as standard conditions). Given that the effective volume of the cryogenic liquefaction separator (7) is V, and the mixing ratio detection module (13) detects that the proportion of C4F7N before liquid injection is... After adsorption by the liquid, the proportion of C4F7N was 10%. Cryogenic liquefaction separation tank before liquid injection (7) The pressure is constant at 3.0 MPa. According to Dalton's law of partial pressures, the partial pressure of C4F7N gas before liquid injection in the cryogenic liquefaction separator (7) can be obtained. and CO2 gas partial pressure They are respectively: (1) (2) Since the volume of liquid C4F7N is extremely small and can be neglected, CO2 gas can be considered as an ideal gas, according to the ideal gas law. (R is a constant), convert CO2 gas to its standard volume under the same molar amounts. : (3) 2) Calculate the standard volume of C4F7N after the nth adsorption. First, calculate the partial pressure of C4F7N after the liquid is adsorbed by the CO2 adsorption tower and enters the cryogenic liquefaction separation tank (7). and CO2 gas partial pressure They are respectively: (4) (5) Calculate the volume under standard conditions. for: (6) The standard volume of C4F7N in the gas after the nth liquid adsorption is: (7) 3) Calculate the total standard gas volume in the cryogenic liquefaction separator (7) during the nth cryogenic separation. (Including the total gas volume of the newly introduced portion to be filled to 3.0 MPa and the gas volume of the gas that was previously adsorbed by the adsorption tower and then refilled into the cryogenic liquefaction separator (7).)

[0022] Because CO2 gas does not decrease during the nth cryogenic liquefaction, the standard volume of CO2 in the cryogenic tank before the nth liquid injection is the same as the standard volume of CO2 in the total gas. Since C4F7N liquefies upon entering the cryogenic tank, the mixing ratio of the total intake gas cannot be directly measured and needs to be calculated. The total intake gas includes the gas adsorbed after the (n-1)th liquid injection and the newly introduced gas. Let the standard volume of the newly introduced gas in the nth cryogenic separation be... Let be the standard volume of C4F7N gas in the cryogenic tank before the nth liquid injection (including the liquid and gaseous portions). Total CO2 gas volume under standard conditions The newly introduced gas mixture ratio is based on the initial mixture ratio detected in the first test. calculate: (8) Sorted as: (9) The total standard volume of C4F7N gas before the nth separation is: (10) 4) Calculate the mass of recovered C4F7N: First, calculate the standard volume of C4F7N recovered in the nth separation. : (11) The density of C4F7N gas under standard conditions is known to be 8.298 kg / m³. 3 Therefore, the mass of C4F7N recovered in the nth separation is: (12) The total mass of C4F7N gas recovered is: (13) The total recovery rate was: (14) An electronic device includes a memory and a processor, the memory being used to store a program that supports the processor in executing the C4F7N separation and recovery measurement method of Embodiment 1, the processor being configured to execute the program stored in the memory.

[0023] A storage medium storing a computer program, which, when executed by a processor, performs the steps of the C4F7N separation and recovery measurement method in Embodiment 1.

[0024] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A continuous separation device for a C4F7N / CO2 mixed gas, characterized in that, include: Air inlet (1), first solenoid valve (2), impurity adsorption tower (3), first compressor (4), pressure sensor (5), temperature sensor (6), cryogenic liquefaction separator (7), second solenoid valve (8), third solenoid valve (9), liquid pump (10), filling port (11), proportional valve (12), mixing ratio detection module (13), fourth solenoid valve (14), first CO2 adsorption tower (15), first heating module (16), fifth solenoid valve (17), sixth solenoid valve (18), seventh solenoid valve (19), second CO2 adsorption tower (20), second heating module (21), eighth solenoid valve (22), ninth solenoid valve (23), vacuum gauge (24), vacuum compressor (25), vacuum discharge port (26); The input end of the first solenoid valve (2) serves as the air inlet (1) of the device. The output end of the first solenoid valve (2) is sealed to the input end of the impurity adsorption tower (3) through a pipe. The output end of the impurity adsorption tower (3) is sealed to the input end of the first compressor (4) through a pipe. The output end of the first compressor (4) is sealed to the input end of the cryogenic liquefaction separator (7) through a pipe. The pressure sensor (5) and temperature sensor (6) are respectively installed on the cryogenic liquefaction separator (7) to detect the pressure and temperature of the cryogenic liquefaction separator (7). The first output end of the cryogenic liquefaction separator (7) is sealed to the input end of the second solenoid valve (8) through a pipe. The second output end of the cryogenic liquefaction separator (7) is sealed to the input end of the third solenoid valve (9). The inlet is sealed by a pipe. The output end of the third solenoid valve (9) is sealed by a pipe to the input end of the liquid pump (10). The output end of the liquid pump (10) serves as the filling port (11). The output end of the second solenoid valve (8) is sealed by a pipe to the input end of the seventh solenoid valve (19). The output end of the seventh solenoid valve (19) is sealed by a pipe to the input end of the eighth solenoid valve (22). The output end of the eighth solenoid valve (22) is sealed by a pipe to the input end of the vacuum compressor (25). The output end of the vacuum compressor (25) serves as the vacuum discharge port (26). The input end of the proportional valve (12) is connected by a pipe to the input end of the first compressor (4). The output end of the proportional valve (12) and the mixing ratio detection module (1) are connected by a pipe to the input end of the first compressor (4). The input end of the third solenoid valve (3) and the output end of the second solenoid valve (8) are sealed together by a three-way pipe. The output end of the mixing ratio detection module (13) is sealed together by a pipe between the output end of the second solenoid valve (8) and the input end of the seventh solenoid valve (19). The input end of the fourth solenoid valve (14) is sealed together by a pipe between the output end of the second solenoid valve (8) and the input end of the seventh solenoid valve (19). The output end of the fourth solenoid valve (14), the input end of the first CO2 adsorption tower (15), and the input end of the fifth solenoid valve (17) are sealed together by a three-way pipe. The output end of the first CO2 adsorption tower (15) and the input end of the sixth solenoid valve (18) are sealed together by a pipe. The output end of the fifth solenoid valve (17) is sealed together by a three-way pipe. The output end of the second CO2 adsorption tower (20) is sealed and connected to the pipeline between the output end of the eighth solenoid valve (22) and the input end of the vacuum compressor (25) via a pipeline. The input end of the second CO2 adsorption tower (20) is sealed and connected to the pipeline between the output end of the seventh solenoid valve (19) and the input end of the eighth solenoid valve (22) via a pipeline. The output end of the second CO2 adsorption tower (20) is sealed and connected to the input end of the ninth solenoid valve (23) via a pipeline. The output end of the sixth solenoid valve (18) is sealed and connected to the output end of the ninth solenoid valve (23) via a pipeline, and then sealed and connected to the output end of the impurity adsorption tower (3) via a pipeline. The vacuum gauge (24) is sealed and installed on the pipeline between the output end of the eighth solenoid valve (22) and the input end of the vacuum compressor (25).The first heating module (16) and the second heating module (21) are respectively installed on the outer walls of the first CO2 adsorption tower (15) and the second CO2 adsorption tower (20), and are used to heat or cool the first CO2 adsorption tower (15) and the second CO2 adsorption tower (20).

2. The C4F7N / CO2 mixed gas continuous separation device according to claim 1, characterized in that, The device's workflow is as follows: S1. The C4F7N / CO2 mixed gas to be separated and purified enters through the inlet (1). The first solenoid valve (2) is opened, and the C4F7N / CO2 mixed gas to be separated and purified enters the impurity adsorption tower (3) for impurity adsorption. The proportional valve (12) is opened, and the C4F7N / CO2 mixed gas to be separated and purified after removing impurities is input into the mixing ratio detection module (13). The proportion of C4F7N in the C4F7N / CO2 mixed gas is detected as follows: ; S2. Start the first compressor (4) and set the boost pressure to 3.0 MPa. Pressurize the C4F7N / CO2 mixed gas (after removing impurities) and input it into the cryogenic liquefaction separator (7). Set the temperature of the cryogenic liquefaction separator (7) to -5℃ to liquefy the C4F7N gas. At this time, open the second solenoid valve (8) and the fourth solenoid valve (14). The mixing ratio detection module (13) detects the proportion of C4F7N gas in the mixed gas before the nth start-up of the liquid injection. After detection, the mixed gas flows to the CO2 adsorption tower; S3. After detection, close the second solenoid valve (8), then open the third solenoid valve (9) and start the liquid pump (10) to fill the cylinder with liquid C4F7N. After the liquid filling is completed, close the third solenoid valve (9) and the liquid pump (10). S4. Open the second solenoid valve (8) and the solenoid valve of the gas path of the first CO2 adsorption tower, and start the first compressor (4). The mixed gas in the cryogenic liquefaction separation tank (7) enters the cryogenic liquefaction separation tank (7) again after passing through the first CO2 adsorption tower. During this process, the mixing ratio detection module (13) continuously detects the mixing ratio. Due to the adsorption effect, the amount of CO2 gas gradually decreases and the proportion of C4F7N gas gradually increases. When the proportion of C4F7N gas reaches 6%, close the fourth solenoid valve (14). After 1 minute, close the sixth solenoid valve (18) and the first compressor (4). At this time, open the second solenoid valve (8), use the mixing ratio detection module (13) to detect the proportion of C4F7N gas, and record the value after 1 minute. This is denoted as the percentage of C4F7N after the nth adsorption. S5, Detection and Acquisition Afterwards, close the second solenoid valve (8) and the mixing ratio detection module (13), start the first compressor (4), open the solenoid valve of the CO2 adsorption tower gas path, pump gas for 3 minutes, and pump all the gas in the CO2 adsorption tower and pipeline into the cryogenic liquefaction separator (7), and control the temperature of the cryogenic liquefaction separator (7) at -5℃, and record the pressure of the cryogenic liquefaction separator (7) at this time. , is the pressure of the cryogenic liquefaction separator (7) after the nth cryogenic separation; then the solenoid valve of the CO2 adsorption tower gas path is closed, the first solenoid valve (2) is opened to continue gas intake, and the next round of cryogenic separation operation is carried out.

3. A method for measuring the C4F7N separation and recovery amount applied to the C4F7N / CO2 mixed gas continuous separation device according to any one of claims 1 to 2, characterized in that, Includes the following steps: 1) Calculate the volume of CO2 in the cryogenic tank before the nth injection under standard conditions. Given that the effective volume of the cryogenic liquefaction separator is V, and the proportion of C4F7N before liquid injection is determined by the mixing ratio detection module, the following is also given. After adsorption by the liquid, the proportion of C4F7N was 10%. Pressure of the cryogenic liquefaction separator before liquid injection The pressure is kept constant at 3.0 MPa; according to Dalton's law of partial pressures, the partial pressure of C4F7N gas before liquid injection in the cryogenic liquefaction separator can be obtained. and CO2 gas partial pressure They are respectively: （1） （2） Since the volume of liquid C4F7N is extremely small and negligible, CO2 gas can be considered an ideal gas, according to the ideal gas law. (R is a constant), convert CO2 gas to its standard volume under the same molar amounts. for: （3） 2) Calculate the standard volume of C4F7N after the nth adsorption. First, calculate the partial pressure of C4F7N gas entering the cryogenic liquefaction separator after the liquid has been adsorbed by the CO2 adsorption tower. and CO2 gas partial pressure They are respectively: （4） （5） Calculate the volume under standard conditions. for: （6） The standard volume of C4F7N in the gas after the nth liquid adsorption is: （7） 3) Calculate the total standard volume of gas in the cryogenic liquefaction separator during the nth cryogenic separation. ; Given that the total intake gas includes the gas after the (n-1)th liquid adsorption and the newly introduced gas, let the standard volume of the newly introduced gas in the nth cryogenic separation be... Let the standard volume of the total C4F7N gas in the cryogenic tank before the nth liquid injection be . The total standard volume of CO2 gas is The newly introduced mixed gas has a mixing ratio based on the initial mixing ratio detected in the first test. calculate: （8） Sorted as: （9） The total standard volume of C4F7N gas before the nth separation is: （10） 4) Calculate the mass of recovered C4F7N Calculate the standard volume of C4F7N recovered in the nth separation. for: （11） The density of C4F7N gas under standard conditions is known to be 8.298 kg / m³. 3 Therefore, the mass of C4F7N recovered in the nth separation is: （12） The total mass of C4F7N gas recovered is: （13） The total recovery rate was: （14）。 4. An electronic device, comprising a memory and a processor, characterized in that, The memory is used to store a program that supports the processor in executing the C4F7N separation and recovery measurement method as described in claim 3, the processor being configured to execute the program stored in the memory.

5. A storage medium storing a computer program, characterized in that, The computer program, when run by the processor, performs the steps of the C4F7N separation and recovery measurement method as described in claim 3.

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