Supercritical carbon dioxide production system and method and medium

Abstract

The invention provides a supercritical carbon dioxide production system and method and a medium, and relates to the technical field of supercritical carbon dioxide conveying, the system comprises a carbon dioxide module, a replacement module, a pressurization module and a heating module, and the carbon dioxide module, the pressurization module and the heating module are all arranged on a main pipeline; the main pipeline is arranged in front of the supercritical carbon dioxide pipeline; the carbon dioxide module is used for injecting liquid-phase carbon dioxide into the main pipeline; the input end of the replacement module is connected with the carbon dioxide module, and the output end of the replacement module is connected with the supercritical carbon dioxide pipeline through an eleventh stop valve; the pressurization module is connected in series with the carbon dioxide module and connected in parallel with the replacement module; and the input end of the heating module is connected with the pressurization module, and the output end of the heating module is connected with the ninth stop valve of the replacement module. Therefore, the production efficiency is improved, and the production time is saved.

Description

Technical Field

[0001] This invention relates to the field of supercritical carbon dioxide transportation technology, and more specifically, to a supercritical carbon dioxide commissioning system, method, and medium. Background Technology

[0002] As the application of supercritical phase carbon dioxide becomes more and more widespread, people's demand for supercritical phase carbon dioxide is increasing.

[0003] Currently, carbon dioxide is generally used as the medium for establishing back pressure when supercritical carbon dioxide pipelines are put into operation. When gaseous carbon dioxide is used to establish back pressure, the high-pressure carbon dioxide expands after entering the pipeline at normal temperature and pressure, resulting in slow back pressure establishment. Furthermore, after establishing back pressure, it is necessary to switch carbon dioxide pressurization equipment to convert the carbon dioxide into a liquid phase, and then further convert the liquid carbon dioxide into a supercritical phase, resulting in low commissioning efficiency.

[0004] When liquid carbon dioxide is used to establish back pressure, due to the Joule-Thompson effect of carbon dioxide vaporization and expansion, dry ice is easily formed when the pipeline temperature drops to the triple point of carbon dioxide, causing pipeline blockage. At the same time, the lowest temperature caused by the vaporization of liquid carbon dioxide in the pipeline can reach -70℃, which greatly exceeds the temperature resistance range of the pipeline and can easily induce brittle fracture of the pipeline during commissioning.

[0005] To address the problems of existing technologies, this invention provides a supercritical carbon dioxide production system, method, and medium. Summary of the Invention

[0006] To address the problems of existing technologies, this invention provides a supercritical carbon dioxide production system, method, and medium. The system includes a carbon dioxide module, a displacement module, a pressurization module, and a heating module. The carbon dioxide module, the pressurization module, and the heating module are all installed on a main pipeline, which is connected to a supercritical carbon dioxide pipeline.

[0007] The carbon dioxide module is used to inject liquid carbon dioxide into the main pipeline;

[0008] The displacement module has its input end connected to the carbon dioxide module and its output end connected to the supercritical carbon dioxide pipeline via an eleventh shut-off valve installed on the main pipeline. It is used to displace the air in the supercritical carbon dioxide pipeline with liquid carbon dioxide and to keep the first temperature and first pressure of the liquid carbon dioxide within a first temperature range and a first pressure range, respectively.

[0009] The pressurization module is connected in series with the carbon dioxide module and in parallel with the displacement module, and is used to pressurize the liquid carbon dioxide in the first temperature range and the first pressure range to obtain the target carbon dioxide, wherein the target carbon dioxide is in the liquid phase;

[0010] The heating module has its input end connected to the pressurization module and its output end connected to the ninth shut-off valve of the displacement module. It is used to heat the target carbon dioxide to obtain supercritical phase carbon dioxide, which is then transmitted to the supercritical carbon dioxide pipeline through the ninth and eleventh shut-off valves.

[0011] According to one embodiment of the present invention, the replacement module includes a sixth shut-off valve and the ninth shut-off valve connected in sequence;

[0012] The sixth shut-off valve has its input end connected to the carbon dioxide module and its output end connected to the output end of the heating module.

[0013] The ninth shut-off valve has its input end connected to the output end of the heating module, and its output end connected to the eleventh shut-off valve.

[0014] According to one embodiment of the present invention, the system further includes: a ball receiving and launching module, disposed on the main pipeline, comprising: a seventh shut-off valve, a ball receiving and launching tube, and a tenth shut-off valve connected in sequence;

[0015] The seventh shut-off valve is connected to the output terminal of the heating module and the output terminal of the sixth shut-off valve;

[0016] The launching and receiving tube is equipped with a pigging device for cleaning the supercritical carbon dioxide pipeline.

[0017] The tenth shut-off valve is connected to the eleventh shut-off valve.

[0018] According to one embodiment of the present invention, the system further includes: a venting module, comprising: an eighth shut-off valve, a first throttle valve, a second throttle valve, and a safety valve;

[0019] The eighth shut-off valve is connected to the launcher / receiver tube and also to the ninth shut-off valve;

[0020] The safety valve is connected in parallel with the eighth shut-off valve and is also connected to the carbon dioxide heater in the heating module and the carbon dioxide booster pump in the pressurization module, for making the operating pressure of the carbon dioxide heater less than the first safety pressure threshold and the operating pressure of the carbon dioxide booster pump less than the second safety pressure threshold.

[0021] The first throttle valve is used to adjust the flow rate of the discharged liquid carbon dioxide in response to receiving a first instruction from the phase monitoring module, so that the first temperature and the first pressure are respectively within the first temperature range and the first pressure range;

[0022] The second throttle valve is used to, in response to receiving the first command, secondarily regulate the flow rate of the discharged liquid carbon dioxide so that the first temperature and the first pressure are respectively within the first temperature range and the first pressure range.

[0023] According to one embodiment of the present invention, the system further includes the phase monitoring module, which includes a pressure sensor, a temperature sensor, a phase analysis submodule, and an execution submodule connected in sequence.

[0024] The pressure sensor is used to acquire the first pressure at the eighth shut-off valve;

[0025] The temperature sensor is used to obtain the first temperature at the eighth shut-off valve;

[0026] The phase analysis submodule is used to determine whether the first pressure is within the first pressure range and whether the first temperature is within the first temperature range.

[0027] The execution submodule is configured to issue the first command to the first throttle valve and the second throttle valve if the first pressure is not within the first pressure range or the first temperature is not within the first temperature range, so as to adjust the opening degree of the first throttle valve and the second throttle valve.

[0028] According to one embodiment of the present invention, the pressurization module includes: a first shut-off valve and the carbon dioxide booster pump connected in sequence;

[0029] The first shut-off valve is connected to the carbon dioxide module;

[0030] The carbon dioxide booster pump is used to pressurize the liquid carbon dioxide within the first temperature range and the first pressure range to obtain the target carbon dioxide.

[0031] According to one embodiment of the present invention, the heating module further includes: a second shut-off valve, a regulating valve, and a third shut-off valve connected in sequence;

[0032] The second shut-off valve is connected to the carbon dioxide booster pump;

[0033] The regulating valve is used to regulate the flow rate of the target carbon dioxide in response to receiving a second command from the phase monitoring module, so that the main pipeline is filled with the target carbon dioxide.

[0034] The third shut-off valve is connected to the launch and receiver module and transmits the target carbon dioxide to the venting module via the launch and receiver module.

[0035] According to one embodiment of the present invention, the pressure sensor is used to acquire a second pressure at the eighth shut-off valve;

[0036] The phase analysis submodule is used to determine whether the second pressure is within the second pressure range;

[0037] The execution submodule is used to issue the second command to the regulating valve to adjust the opening degree of the regulating valve if the pressure is not within the second pressure range.

[0038] According to one embodiment of the present invention, the pressurization module further includes: a pressure regulating valve, the input end of which is connected to the carbon dioxide booster pump, and the output end of which is connected to the second shut-off valve, for pressurizing the target carbon dioxide to obtain the first target carbon dioxide.

[0039] According to one embodiment of the present invention, the heating module further includes: a fourth shut-off valve, a carbon dioxide heater, and a fifth shut-off valve connected in sequence;

[0040] The fourth shut-off valve is connected in parallel with the second shut-off valve and in series with the pressure regulating valve.

[0041] The carbon dioxide heater is used to heat the first target carbon dioxide to obtain the supercritical phase carbon dioxide;

[0042] The fifth shut-off valve is connected to the input end of the ninth shut-off valve.

[0043] According to one embodiment of the present invention, the regulating valve is further configured to regulate the flow rate of the target carbon dioxide in response to receiving a third instruction from the phase monitoring module, so that the main pipeline is filled with the supercritical phase carbon dioxide.

[0044] According to one embodiment of the present invention, the temperature sensor is used to acquire a second temperature at the eighth shut-off valve;

[0045] The phase analysis submodule is used to determine whether the second temperature is within the second temperature range;

[0046] The execution submodule is further configured to, if the second temperature is not within the second temperature range, issue the third instruction to the regulating valve to adjust the opening degree of the regulating valve.

[0047] According to one embodiment of the present invention, before purging the air in the supercritical carbon dioxide pipeline, the first shut-off valve, the second shut-off valve, the third shut-off valve, the fourth shut-off valve, the fifth shut-off valve, the seventh shut-off valve, and the eighth shut-off valve are opened to purge the air in the main pipeline with the liquid carbon dioxide.

[0048] According to another aspect of the present invention, a method for supercritical carbon dioxide production is also provided, executed by a system as described in any of the preceding claims, the method comprising:

[0049] Liquid carbon dioxide is injected into a main pipeline connected to a supercritical carbon dioxide pipeline; the liquid carbon dioxide replaces the air in the supercritical carbon dioxide pipeline and brings the first temperature and first pressure of the liquid carbon dioxide to a first temperature range and a first pressure range, respectively.

[0050] The liquid carbon dioxide in the first temperature range and the first pressure range is pressurized to obtain target carbon dioxide, wherein the target carbon dioxide is in the liquid phase;

[0051] The target carbon dioxide is heated to obtain supercritical phase carbon dioxide, which is then transported to the supercritical carbon dioxide pipeline.

[0052] According to another aspect of the invention, a storage medium is also provided, comprising a series of instructions for performing the steps of the method as described in any of the preceding claims.

[0053] This invention provides a supercritical carbon dioxide production system, method, and medium, which have the following advantages compared with the prior art:

[0054] This invention comprises a carbon dioxide module, a displacement module, a pressurization module, and a heating module. The carbon dioxide module injects liquid carbon dioxide, and the displacement module displaces the air in the supercritical carbon dioxide pipeline, bringing the first temperature and first pressure of the liquid carbon dioxide within a first temperature range and a first pressure range, respectively, thus achieving displacement of the supercritical carbon dioxide pipeline. Next, the pressurization module pressurizes the liquid carbon dioxide within the first temperature and first pressure range to obtain the target carbon dioxide. Then, the heating module heats the target carbon dioxide to obtain supercritical phase carbon dioxide. In this way, on the one hand, the production efficiency is improved, the production time is saved, and the stability of the supercritical phase carbon dioxide is ensured; on the other hand, blockage of the main pipeline and the supercritical carbon dioxide pipeline is avoided, ensuring the normal operation of the main pipeline and the supercritical carbon dioxide pipeline, thus taking into account the reliability and safety of production and operation.

[0055] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the description, claims, and drawings. Attached Figure Description

[0056] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with the embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0057] Figure 1 A schematic diagram of a supercritical carbon dioxide production system according to an embodiment of the present invention is shown;

[0058] Figure 2 A schematic diagram of a supercritical carbon dioxide production system according to yet another embodiment of the present invention is shown.

[0059] Figure 3 A schematic diagram of a supercritical carbon dioxide production system according to another embodiment of the present invention is shown;

[0060] Figure 4 A schematic diagram of a venting module according to an embodiment of the present invention is shown.

[0061] Figure 5 A flowchart of a supercritical carbon dioxide production method according to an embodiment of the present invention is shown.

[0062] In the accompanying drawings, the same parts use the same reference numerals. Also, the drawings are not drawn to scale.

[0063] The meanings of the reference numerals in the attached figures are as follows:

[0064] 10 – Main pipeline; 20 – Supercritical carbon dioxide pipeline; 100 – Carbon dioxide module

[0065] 200 – Replacement Module; 201 – Sixth Shut-off Valve; 202 – Ninth Shut-off Valve

[0066] 300 – Pressurization module; 301 – First shut-off valve; 302 – Carbon dioxide booster pump

[0067] 303 – Pressure regulating valve; 400 – Heating module; 401 – Second shut-off valve

[0068] 402 – Control valve; 403 – Third shut-off valve; 404 – Fourth shut-off valve

[0069] 405 – Carbon dioxide heater; 406 – Fifth shut-off valve; 500 – Ball launcher / receiver module

[0070] 501 – Seventh shut-off valve; 502 – Ball receiver / launcher tube; 503 – Tenth shut-off valve

[0071] 600 – Vent Module; 601 – Eighth Shut-off Valve; 602 – First Throttle Valve

[0072] 603 – Second throttle valve; 604 – Safety valve; 701 – Eleventh shut-off valve Detailed Implementation

[0073] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0074] When liquid carbon dioxide is used to establish back pressure, the liquid carbon dioxide entering the pipeline rapidly vaporizes, and the pressure increases abruptly. When the pressure exceeds the pressure when carbon dioxide is injected, gas lock is easily formed, making it difficult to inject liquid carbon dioxide. Further vaporization can easily lead to pipeline overpressure.

[0075] The prior art (CN111536420A) mentions a safe filling unit and method for liquid ethane pipelines after maintenance, including: a main line unit, a main line valve chamber unit, an ethane filling unit, and a pipeline temperature and pressure detection unit. The main line valve chamber unit is responsible for venting and restarting the upstream and downstream pipelines of the valve chamber, and also provides a channel for main line pipeline replacement. The ethane filling unit is used to introduce ethane from the upstream main line and heat and adjust its temperature before sending it to the downstream main line to be restarted before restarting the downstream main line. This invention, based on the functional requirement of restarting a liquid ethane pipeline after maintenance and venting, and taking advantage of the low-pressure vaporization and cryogenic characteristics of liquid ethane, effectively controls the low-temperature problem of the medium during the filling process of the isolated maintenance section of the liquid ethane pipeline by adopting measures such as using a valve chamber bypass to provide a filling medium channel in the upstream pipeline section, using external equipment for vaporization and heating of the initial filling medium, and pressurizing and liquefying during the middle and later stages of filling. This ensures the safe operation of the liquid ethane pipeline and provides effective protection for its safe operation. The structure differs from that of the supercritical carbon dioxide production system of this invention.

[0076] The existing technology (CN212273709U) mentions a safe filling system for liquid ethane pipelines after maintenance, including: a main pipeline system, a main pipeline valve chamber system, an ethane filling system, and a pipeline temperature and pressure detection system. The main pipeline valve chamber system is responsible for venting and restarting the upstream and downstream pipelines of the valve chamber, and also provides a channel for pipeline replacement. The ethane filling system is used to introduce ethane from the upstream main pipeline and heat and adjust its temperature before sending it to the downstream main pipeline to be restarted before restarting. This invention, based on the functional requirement of restarting a liquid ethane pipeline after maintenance and venting, and leveraging the low-pressure vaporization and cryogenic characteristics of liquid ethane, effectively controls the low-temperature problem of the medium during the filling process of the isolated maintenance section of the liquid ethane pipeline by adopting measures such as using a valve chamber bypass to provide a filling medium channel in the upstream pipeline section, using external equipment for vaporization and heating of the initial filling medium, and pressurizing and liquefying during the middle and later stages of filling. This ensures the safe operation of the liquid ethane pipeline and provides effective protection for its safe operation. This differs in structure from the supercritical carbon dioxide production system of this invention.

[0077] To address the aforementioned deficiencies in the prior art, this invention provides a supercritical carbon dioxide production system, method, and medium. Figure 1 A schematic diagram of a supercritical carbon dioxide production system according to an embodiment of the present invention is shown. Figure 2 A schematic diagram of a supercritical carbon dioxide production system according to yet another embodiment of the present invention is shown. Figure 3 A schematic diagram of a supercritical carbon dioxide production system according to another embodiment of the present invention is shown, as follows. Figure 1 , Figure 2 and Figure 3 As shown, the system includes: a carbon dioxide module 100, a displacement module 200, a pressurization module 300, and a heating module 400; the carbon dioxide module 100, the pressurization module 300, and the heating module 400 are all installed on the main pipeline 10; the main pipeline 10 is connected to the supercritical carbon dioxide pipeline 20.

[0078] Carbon dioxide module 100 is used to inject liquid carbon dioxide into the main pipeline 10;

[0079] The displacement module 200 has its input end connected to the carbon dioxide module 100 and its output end connected to the supercritical carbon dioxide pipeline 20 via the eleventh shut-off valve 701. It is used to replace the air in the supercritical carbon dioxide pipeline 20 with liquid carbon dioxide and to keep the first temperature and first pressure of the liquid carbon dioxide within the first temperature range and the first pressure range, respectively.

[0080] The pressurization module 300 is connected in series with the carbon dioxide module 100 and in parallel with the displacement module 200. It is used to pressurize liquid carbon dioxide in a first temperature range and a first pressure range to obtain the target carbon dioxide.

[0081] The heating module 400 has its input end connected to the pressurization module 300 and its output end connected to the ninth shut-off valve 202 of the displacement module 200. It is used to heat the target carbon dioxide to obtain supercritical phase carbon dioxide, which is then transmitted to the supercritical carbon dioxide pipeline 20 through the ninth shut-off valve 202 and the eleventh shut-off valve 701 installed on the main pipeline 10.

[0082] The target carbon dioxide can be a cryogenic liquid phase. For example, the temperature and pressure at the ninth shut-off valve 202 can be monitored by temperature and pressure sensors in the phase monitoring module, so that the first temperature and first pressure of the liquid carbon dioxide at the ninth shut-off valve 202 are within a first temperature range and a first pressure range, respectively.

[0083] This invention comprises a carbon dioxide module, a displacement module, a pressurization module, and a heating module. The carbon dioxide module injects liquid carbon dioxide, and the displacement module displaces the air in the supercritical carbon dioxide pipeline, bringing the first temperature and first pressure of the liquid carbon dioxide within a first temperature range and a first pressure range, respectively, thus achieving displacement of the supercritical carbon dioxide pipeline. Next, the pressurization module pressurizes the liquid carbon dioxide within the first temperature and first pressure range to obtain the target carbon dioxide. Then, the heating module heats the target carbon dioxide to obtain supercritical phase carbon dioxide. In this way, on the one hand, the production efficiency is improved, the production time is saved, and the stability of the supercritical phase carbon dioxide is ensured; on the other hand, blockage of the main pipeline and the supercritical carbon dioxide pipeline is avoided, ensuring the normal operation of the main pipeline and the supercritical carbon dioxide pipeline, thus taking into account the reliability and safety of production and operation.

[0084] like Figure 2 As shown, before replacing the air in the supercritical carbon dioxide pipeline 20, the first shut-off valve 301, the second shut-off valve 401, the third shut-off valve 403, the fourth shut-off valve 404, the fifth shut-off valve 406, the seventh shut-off valve 501, and the eighth shut-off valve 601 are opened to replace the air in the main pipeline 10 with liquid carbon dioxide.

[0085] According to the pipeline transportation process requirements, carbon dioxide module 100, pressurization module 300, heating module 400, launcher / receiver module 500, and venting module 600 are installed along the pipeline. After the pipeline construction is completed, the remaining medium in the pipeline is air. The first shut-off valve 301, the second shut-off valve 401, the third shut-off valve 403, the fourth shut-off valve 404, the fifth shut-off valve 406, the seventh shut-off valve 501, and the eighth shut-off valve 601 in each module are opened in sequence. Liquid carbon dioxide is used to purge and replace each module. The oxygen content is measured by an oxygen sensor placed in the venting module 600. If the oxygen content at the venting module 600 is less than 0.5%, it is determined that the main pipeline 10 has been replaced. At this time, the main pipeline 10 contains liquid carbon dioxide.

[0086] like Figure 3 As shown, the replacement module 200 includes a sixth shut-off valve 201 and a ninth shut-off valve 202 connected in sequence;

[0087] The sixth shut-off valve 201 has its input end connected to the carbon dioxide module 100 and its output end connected to the output end of the heating module 400.

[0088] The ninth shut-off valve 202 has its input end connected to the output end of the heating module 400, and its output end connected to the eleventh shut-off valve 701.

[0089] like Figure 2 As shown, the system also includes: a ball receiving and launching module 500, which is installed on the main pipeline 10, including: a seventh shut-off valve 501, a ball receiving and launching tube 502, and a tenth shut-off valve 503 connected in sequence;

[0090] The seventh shut-off valve 501 is connected to the output terminal of the heating module 400 and the output terminal of the sixth shut-off valve 201;

[0091] The launcher and receiver tube 502 is equipped with a pigging device for cleaning the supercritical carbon dioxide pipeline 20.

[0092] The tenth shut-off valve 503 is connected to the eleventh shut-off valve 701.

[0093] During the replacement of air in the supercritical carbon dioxide pipeline 20, the sixth shut-off valve 201, the seventh shut-off valve 501, the tenth shut-off valve 503, and the eleventh shut-off valve 701 are opened sequentially. When liquid carbon dioxide enters the pipeline at normal temperature and pressure, it vaporizes, causing the pipeline temperature to drop. The pressure generated by the vaporization of the liquid carbon dioxide pushes the pig from the launcher / receiver cylinder 502 into the supercritical carbon dioxide pipeline 20 to clean it. Next, the ninth shut-off valve 202 is opened, and the seventh shut-off valve 501 and the tenth shut-off valve 503 are closed, continuously injecting liquid carbon dioxide. The vaporization of the liquid carbon dioxide propels the pig to move downstream of the supercritical carbon dioxide pipeline 20 to replace the air in the pipeline. The pig also isolates the injected liquid carbon dioxide from the air at its inlet.

[0094] When supercritical carbon dioxide is obtained, the ninth shut-off valve 202 is closed, and the seventh shut-off valve 501 and the tenth shut-off valve 503 are opened in sequence. The pig is pushed out from the pig receiving and launching cylinder 502 and pushed into the supercritical carbon dioxide pipeline 20 to clean the supercritical carbon dioxide pipeline 20. Then, the ninth shut-off valve 202 is opened and the seventh shut-off valve 501 and the tenth shut-off valve 503 are closed. Supercritical carbon dioxide is continuously injected into the supercritical carbon dioxide pipeline 20. Using the pressure difference before and after the pig, the pig is pushed to move downstream to the station. The supercritical carbon dioxide at the rear end is isolated from the cryogenic liquid at the front end of the pig through the pig. After the downstream pig receiving cylinder receives the pig, liquid phase carbon dioxide is continued to be injected into the main pipeline 10.

[0095] like Figure 4 As shown, the system also includes: a venting module 600, which includes: an eighth shut-off valve 601, a first throttle valve 602, a second throttle valve 603, and a safety valve 604;

[0096] The eighth shut-off valve 601 is connected to the ball receiving and launching tube 502 and also to the ninth shut-off valve 202;

[0097] Safety valve 604 is connected in parallel with eighth shut-off valve 601, and is also connected to carbon dioxide heater 405 in heating module 400 and carbon dioxide booster pump 302 in pressurization module 300. It is used to make the operating pressure of carbon dioxide heater 405 less than the first safety pressure threshold and the operating pressure of carbon dioxide booster pump 302 less than the second safety pressure threshold.

[0098] The first throttle valve 602 is used to adjust the flow rate of the discharged liquid carbon dioxide in response to receiving the first instruction from the phase monitoring module, so that the first temperature and the first pressure are respectively within the first temperature range and the first pressure range;

[0099] The second throttle valve 603 is used to, in response to receiving the first command, regulate the flow rate of the discharged liquid carbon dioxide in a secondary manner so that the first temperature and the first pressure are respectively within the first temperature range and the first pressure range.

[0100] In one possible embodiment, the system further includes a phase state monitoring module, comprising a pressure sensor, a temperature sensor, a phase state analysis submodule, and an execution submodule connected in sequence.

[0101] A pressure sensor is used to acquire the first pressure at the eighth shut-off valve 601;

[0102] A temperature sensor is used to obtain the first temperature at the eighth shut-off valve 601;

[0103] The phase analysis submodule is used to determine whether the first pressure is within the first pressure range and whether the first temperature is within the first temperature range;

[0104] The execution submodule is used to issue a first command to the first throttle valve 602 and the second throttle valve 603 if the first pressure is not within the first pressure range or the first temperature is not within the first temperature range, so as to adjust the opening degree of the first throttle valve 602 and the second throttle valve 603.

[0105] During the replacement process, the temperature and pressure at the eighth shut-off valve 601 in the venting module 600 can be monitored using temperature and pressure sensors in the phase monitoring module. Based on the first temperature and pressure, the openings of the first throttle valve 602 and the second throttle valve 603 are adjusted to ensure that the first pressure and temperature are within the first temperature range, and then the first throttle valve 602 and the second throttle valve 603 are closed. The first temperature range can be the temperature at which liquid carbon dioxide is injected, for example, -10 to -15°C; the first pressure range can be the pressure at which liquid carbon dioxide is injected, for example, 1 to 2 MPa. This avoids the gas resistance phenomenon caused by excessive vaporization pressure after the liquid carbon dioxide is injected, ensuring the safety of the pipeline.

[0106] like Figure 3 As shown, the pressurization module 300 includes a first shut-off valve 301 and a carbon dioxide booster pump 302 connected in sequence.

[0107] The first shut-off valve 301 is connected to the carbon dioxide module 100;

[0108] The carbon dioxide booster pump 302 is used to pressurize liquid carbon dioxide within a first temperature range and a first pressure range to obtain the target carbon dioxide.

[0109] After replacement, the sixth shut-off valve 201 is closed, and the carbon dioxide booster pump 302 and the first shut-off valve 301 are turned on to pressurize the liquid carbon dioxide in the first temperature range and the first pressure range to obtain the target carbon dioxide. The discharge pressure of the carbon dioxide booster pump 302 can be 2 to 4 MPa. At this time, the temperature inside the main pipeline 10 can be obtained by the temperature sensor in the phase state monitoring module as -15 to -20℃. Then, the target carbon dioxide can be obtained by looking up the existing phase state diagram.

[0110] like Figure 3 As shown, the heating module 400 also includes: a second shut-off valve 401, a regulating valve 402, and a third shut-off valve 403 connected in sequence;

[0111] The second shut-off valve 401 is connected to the carbon dioxide booster pump 302;

[0112] The regulating valve 402 is used to regulate the flow rate of the target carbon dioxide in response to receiving a second command from the phase state monitoring module, so that the main pipeline 10 is filled with the target carbon dioxide.

[0113] The third shut-off valve 403 is connected to the launch and receiver module 500 and transmits the target carbon dioxide to the venting module 600 via the launch and receiver module 500.

[0114] The system can open the second shut-off valve 401, regulating valve 402, third shut-off valve 403, seventh shut-off valve 501, eighth shut-off valve 601, first throttle valve 602, second throttle valve 603, and safety valve 604, so that the target carbon dioxide can enter the venting module 600 through the second shut-off valve 401, regulating valve 402, third shut-off valve 403, and seventh shut-off valve 501 in the heating module 400. This avoids the gas resistance phenomenon caused by excessive vaporization pressure after liquid carbon dioxide is injected into the main pipeline 10, and improves the safety of the main pipeline 10.

[0115] In one possible embodiment, a pressure sensor is used to acquire the second pressure at the eighth shut-off valve 601;

[0116] The phase analysis submodule is used to determine whether the second pressure is within the second pressure range;

[0117] The execution submodule is used to issue a second command to the regulating valve 402 if the pressure is not within the second pressure range, so as to adjust the opening of the regulating valve 402.

[0118] After pressurization, the second pressure at the eighth shut-off valve 601 can be obtained through the pressure sensor in the phase monitoring module. The phase analysis submodule in the phase monitoring module can also determine whether the pressure at the eighth shut-off valve 601 is within the second pressure range, so as to determine whether the main pipeline 10 is filled with the target carbon dioxide. The second pressure range can be 2 to 4 MPa.

[0119] When the execution submodule determines that the carbon dioxide pressure at the eighth shut-off valve 601 is not within the second pressure range, it issues a second command to the regulating valve 402 to adjust the opening of the regulating valve 402 until the pressure in the main pipeline 10 is within the second target pressure range, and then closes the regulating valve 402, the first throttle valve 602 and the second throttle valve 603.

[0120] like Figure 3 As shown, the pressurization module 300 also includes a pressure regulating valve 303, the input end of which is connected to the carbon dioxide booster pump 302, and the output end of which is connected to the fourth shut-off valve 404, for pressurizing the target carbon dioxide to obtain the first target carbon dioxide.

[0121] When the main pipeline 10 is filled with the target carbon dioxide, the pressure regulating valve 303 is opened to pressurize the target carbon dioxide to the normal operating pressure of the main pipeline 10 (e.g., 8-12 MPa), thus obtaining the first target carbon dioxide. During the pressurization process, the venting module 600 is opened to adjust the pressure of the main pipeline 10 to be less than the maximum allowable pressure of the main pipeline 10.

[0122] like Figure 3 As shown, the heating module 400 also includes: a fourth shut-off valve 404, a carbon dioxide heater 405, and a fifth shut-off valve 406 connected in sequence;

[0123] The fourth shut-off valve 404 is connected in parallel with the second shut-off valve 401 and in series with the pressure regulating valve 303;

[0124] Carbon dioxide heater 405 is used to heat the first target carbon dioxide to obtain supercritical phase carbon dioxide;

[0125] The fifth shut-off valve 406 is connected to the input end of the ninth shut-off valve 202.

[0126] After obtaining the first target carbon dioxide, the fourth shut-off valve 404, the carbon dioxide heater 405, and the fifth shut-off valve 406 are opened to heat the first target carbon dioxide to the normal operating temperature of the main pipeline 10 (e.g., 35-45°C). At this temperature, the carbon dioxide is in the supercritical phase. During the heating process, the venting module 600 is opened to adjust the pressure of the main pipeline 10 to be less than the maximum allowable pressure of the main pipeline 10.

[0127] In one possible embodiment, the regulating valve 402 is also used to regulate the flow rate of the target carbon dioxide in response to receiving a third instruction from the phase monitoring module, so that the main pipeline 10 is filled with supercritical phase carbon dioxide.

[0128] In one possible embodiment, a temperature sensor is used to acquire a second temperature at the eighth shut-off valve 601;

[0129] The phase analysis submodule is used to determine whether the second temperature is within the second temperature range.

[0130] The execution submodule is also used to issue a third command to the regulating valve 402 to adjust the opening degree of the regulating valve 402 if the second temperature is not within the second temperature range.

[0131] After pressurization and heating, the second temperature at the eighth shut-off valve 601 can be detected by the temperature sensor in the phase monitoring module. The phase state analysis submodule in the phase monitoring module can also determine whether the second temperature is within a second temperature range, thus confirming whether the main pipeline 10 is entirely filled with supercritical carbon dioxide. The second temperature range can be 35–45°C. The execution submodule, if the second temperature is not within the second temperature range, issues a third command to the regulating valve 402 to adjust its opening, ensuring the supercritical carbon dioxide is within the second temperature range. When the main pipeline 10 is entirely filled with supercritical carbon dioxide, the regulating valve 402 is closed. During this process, the venting module 600 is activated to ensure the pressure in the main pipeline 10 is below its maximum allowable operating pressure, guaranteeing the safety of the main pipeline 10.

[0132] According to another aspect of the present invention, a method for supercritical carbon dioxide production is also provided, which is executed by a supercritical carbon dioxide production system. Figure 5 A flowchart of a supercritical carbon dioxide production method according to an embodiment of the present invention is shown, the method comprising:

[0133] S101, inject liquid carbon dioxide into the main pipeline, which is connected to the supercritical carbon dioxide pipeline;

[0134] S102, the air in the supercritical carbon dioxide pipeline is replaced by liquid carbon dioxide and the first temperature and first pressure of the liquid carbon dioxide are respectively within a first temperature range and a first pressure range.

[0135] S103, pressurize liquid carbon dioxide within a first temperature range and a first pressure range to obtain target carbon dioxide, wherein the target carbon dioxide is a liquid phase;

[0136] S104, the target carbon dioxide is heated to obtain supercritical phase carbon dioxide, which is then transported to the supercritical carbon dioxide pipeline.

[0137] The supercritical carbon dioxide production method provided by this invention can also be used in conjunction with a computer-readable storage medium. The storage medium stores a computer program, which is executed to run the supercritical carbon dioxide production method. The computer program is capable of executing computer instructions, which include computer program code. The computer program code can be in the form of source code, object code, executable file, or some intermediate form.

[0138] Computer-readable storage media can include: any entity or device capable of carrying computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc.

[0139] It should be noted that the contents of computer-readable storage media may be appropriately added to or subtracted from the contents according to the requirements of legislation and patent practice in a jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable storage media may not include electrical carrier signals and telecommunication signals.

[0140] In summary, this invention provides a supercritical carbon dioxide production system, method, and medium, which have the following advantages compared with the prior art:

[0141] This invention comprises a carbon dioxide module, a displacement module, a pressurization module, and a heating module. The carbon dioxide module injects liquid carbon dioxide, and the displacement module displaces the air in the supercritical carbon dioxide pipeline, bringing the first temperature and first pressure of the liquid carbon dioxide within a first temperature range and a first pressure range, respectively, thus achieving displacement of the supercritical carbon dioxide pipeline. Next, the pressurization module pressurizes the liquid carbon dioxide within the first temperature and first pressure range to obtain the target carbon dioxide. Then, the heating module heats the target carbon dioxide to obtain supercritical phase carbon dioxide. In this way, on the one hand, the production efficiency is improved, the production time is saved, and the stability of the supercritical phase carbon dioxide is ensured; on the other hand, blockage of the main pipeline and the supercritical carbon dioxide pipeline is avoided, ensuring the normal operation of the main pipeline and the supercritical carbon dioxide pipeline, thus taking into account the reliability and safety of production and operation.

[0142] It should be understood that the embodiments disclosed herein are not limited to the specific structures, processing steps, or materials disclosed herein, but should be extended to equivalent substitutions of these features as understood by those skilled in the art. It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

[0143] In the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0144] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0145] Certain terms are used throughout this application to refer to specific system components. As those skilled in the art will recognize, the same components may often be referred to by different names, and therefore this application is not intended to distinguish those components that differ only in name and not in function. In this application, the terms “comprise,” “include,” and “have” are used in an open-ended manner and should therefore be interpreted as meaning “including, but not limited to…”. Furthermore, the terms “substantially,” “materially,” or “approximately” as used herein refer to industry-accepted tolerances for the corresponding terms. The term “coupling,” as may be used herein, includes direct coupling and indirect coupling via additional components, elements, circuits, or modules, wherein, for indirect coupling, the intermediate component, element, circuit, or module does not alter the information of the signal but may adjust its current level, voltage level, and / or power level. Inferred coupling (e.g., one element is inferredly coupled to another element) includes direct and indirect coupling between two elements in the same manner as “coupling.”

[0146] The phrase "an embodiment" or "an embodiment" used in this specification means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Therefore, the phrase "an embodiment" or "an embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment.

[0147] The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described in order to better illustrate the principles and practical application of the invention, and to enable those skilled in the art to understand the invention and to design various embodiments with various modifications suitable for a particular purpose.

[0148] While the embodiments disclosed in this invention are as described above, the content is merely for the purpose of facilitating understanding of the invention and is not intended to limit the invention. Any person skilled in the art to which this invention pertains may make any modifications and variations in form and detail of the implementation without departing from the spirit and scope disclosed herein; however, the scope of patent protection for this invention shall still be determined by the scope defined in the appended claims.

Claims

1. A supercritical carbon dioxide production system, characterized in that, The system includes a carbon dioxide module, a displacement module, a pressurization module, and a heating module. The carbon dioxide module, the pressurization module, and the heating module are all installed on the main pipeline, which is connected to the supercritical carbon dioxide pipeline. The carbon dioxide module is used to inject liquid carbon dioxide into the main pipeline; The displacement module has its input end connected to the carbon dioxide module and its output end connected to the supercritical carbon dioxide pipeline via an eleventh shut-off valve installed on the main pipeline. It is used to displace the air in the supercritical carbon dioxide pipeline with liquid carbon dioxide and to keep the first temperature and first pressure of the liquid carbon dioxide within a first temperature range and a first pressure range, respectively. The pressurization module is connected in series with the carbon dioxide module and in parallel with the displacement module, and is used to pressurize the liquid carbon dioxide in the first temperature range and the first pressure range to obtain the target carbon dioxide, wherein the target carbon dioxide is a liquid phase; The heating module has its input end connected to the pressurization module and its output end connected to the ninth shut-off valve of the displacement module. It is used to heat the target carbon dioxide to obtain supercritical phase carbon dioxide, which is then transmitted to the supercritical carbon dioxide pipeline through the ninth and eleventh shut-off valves.

2. The system as described in claim 1, characterized in that, The replacement module includes a sixth shut-off valve and a ninth shut-off valve connected in sequence; The sixth shut-off valve has its input end connected to the carbon dioxide module and its output end connected to the output end of the heating module. The ninth shut-off valve has its input end connected to the output end of the heating module, and its output end connected to the eleventh shut-off valve.

3. The system as described in claim 2, characterized in that, The system also includes a ball receiving and launching module, which is installed on the main pipeline and includes a seventh shut-off valve, a ball receiving and launching tube, and a tenth shut-off valve connected in sequence. The seventh shut-off valve is connected to the output terminal of the heating module and the output terminal of the sixth shut-off valve; The launching and receiving tube is equipped with a pigging device for cleaning the supercritical carbon dioxide pipeline. The tenth shut-off valve is connected to the eleventh shut-off valve.

4. The system as described in claim 3, characterized in that, The system also includes: a venting module, comprising: an eighth shut-off valve, a first throttle valve, a second throttle valve, and a safety valve; The eighth shut-off valve is connected to the launcher / receiver tube and also to the ninth shut-off valve; The safety valve is connected in parallel with the eighth shut-off valve and is also connected to the carbon dioxide heater in the heating module and the carbon dioxide booster pump in the pressurization module, for making the operating pressure of the carbon dioxide heater less than the first safety pressure threshold and the operating pressure of the carbon dioxide booster pump less than the second safety pressure threshold. The first throttle valve is used to adjust the flow rate of the discharged liquid carbon dioxide in response to receiving a first instruction from the phase monitoring module, so that the first temperature and the first pressure are respectively within the first temperature range and the first pressure range; The second throttle valve is used to, in response to receiving the first command, secondarily regulate the flow rate of the discharged liquid carbon dioxide so that the first temperature and the first pressure are respectively within the first temperature range and the first pressure range.

5. The system as described in claim 4, characterized in that, The system also includes the phase monitoring module, which comprises a pressure sensor, a temperature sensor, a phase analysis submodule, and an execution submodule connected in sequence. The pressure sensor is used to acquire the first pressure at the eighth shut-off valve; The temperature sensor is used to obtain the first temperature at the eighth shut-off valve; The phase analysis submodule is used to determine whether the first pressure is within the first pressure range and whether the first temperature is within the first temperature range. The execution submodule is configured to issue the first command to the first throttle valve and the second throttle valve to adjust the opening degree of the first throttle valve and the second throttle valve if the first pressure is not within the first pressure range or the first temperature is not within the first temperature range.

6. The system as described in claim 5, characterized in that, The pressurization module includes: a first shut-off valve and the carbon dioxide booster pump connected in sequence; The first shut-off valve is connected to the carbon dioxide module; The carbon dioxide booster pump is used to pressurize the liquid carbon dioxide within the first temperature range and the first pressure range to obtain the target carbon dioxide.

7. The system as described in claim 6, characterized in that, The heating module further includes: a second shut-off valve, a regulating valve, and a third shut-off valve connected in sequence; The second shut-off valve is connected to the carbon dioxide booster pump; The regulating valve is used to regulate the flow rate of the target carbon dioxide in response to receiving a second command from the phase monitoring module, so that the main pipeline is filled with the target carbon dioxide. The third shut-off valve is connected to the launch and receiver module and transmits the target carbon dioxide to the venting module via the launch and receiver module.

8. The system as described in claim 7, characterized in that, The pressure sensor is used to acquire the second pressure at the eighth shut-off valve; The phase analysis submodule is used to determine whether the second pressure is within the second pressure range; The execution submodule is used to issue the second command to the regulating valve to adjust the opening degree of the regulating valve if the pressure is not within the second pressure range.

9. The system as described in claim 8, characterized in that, The pressurization module further includes a pressure regulating valve, the input end of which is connected to the carbon dioxide booster pump, and the output end of which is connected to the second shut-off valve, for pressurizing the target carbon dioxide to obtain the first target carbon dioxide.

10. The system as described in claim 9, characterized in that, The heating module further includes: a fourth shut-off valve, a carbon dioxide heater, and a fifth shut-off valve connected in sequence; The fourth shut-off valve is connected in parallel with the second shut-off valve and in series with the pressure regulating valve. The carbon dioxide heater is used to heat the first target carbon dioxide to obtain the supercritical phase carbon dioxide; The fifth shut-off valve is connected to the input end of the ninth shut-off valve.

11. The system as claimed in claim 10, characterized in that, The regulating valve is also used to regulate the flow rate of the target carbon dioxide in response to receiving a third command from the phase monitoring module, so that the main pipeline is filled with the supercritical phase carbon dioxide.

12. The system as claimed in claim 11, characterized in that, The temperature sensor is used to obtain the second temperature at the eighth shut-off valve; The phase analysis submodule is used to determine whether the second temperature is within the second temperature range; The execution submodule is further configured to, if the second temperature is not within the second temperature range, issue the third instruction to the regulating valve to adjust the opening degree of the regulating valve.

13. The system as described in claim 12, characterized in that, Before purging the air in the supercritical carbon dioxide pipeline, the first shut-off valve, the second shut-off valve, the third shut-off valve, the fourth shut-off valve, the fifth shut-off valve, the seventh shut-off valve, and the eighth shut-off valve are opened to purge the air in the main pipeline with liquid carbon dioxide.

14. A method for supercritical carbon dioxide production, characterized in that, The method, performed by the system as described in any one of claims 1-13, comprises: Liquid carbon dioxide is injected into a main pipeline, which is connected to a supercritical carbon dioxide pipeline; The air in the supercritical carbon dioxide pipeline is replaced by the liquid carbon dioxide, and the first temperature and first pressure of the liquid carbon dioxide are respectively within a first temperature range and a first pressure range. The liquid carbon dioxide in the first temperature range and the first pressure range is pressurized to obtain target carbon dioxide, wherein the target carbon dioxide is in the liquid phase; The target carbon dioxide is heated to obtain supercritical phase carbon dioxide, which is then transported to the supercritical carbon dioxide pipeline.

15. A storage medium, characterized in that, It includes a series of instructions for performing the steps of the method as described in claim 14.

Images