Pipeline gas replacement characteristic test system based on modular dead cavity

Abstract

The invention discloses a pipeline gas replacement characteristic test system based on a modular dead cavity, relates to the technical field of gas replacement characteristic tests, and aims to solve the problem that a traditional gas replacement characteristic test device cannot obtain gas concentration changes in a complex dead cavity structure in an actual working condition, so that a dead cavity gas replacement rule is difficult to obtain. Comprising a gas source assembly, the gas source assembly is connected with a gas supply pipeline through a pipeline, the gas supply pipeline is sequentially connected with a measured dead cavity pipeline and an exhaust pipeline, a flow control unit and a temperature control unit are arranged between the gas source assembly and the gas supply pipeline, the tail end of the measured dead cavity pipeline is connected with a measuring module, and the exhaust pipeline is connected with a pressure control unit. According to the pipeline gas replacement characteristic test system based on the modularized dead cavity, the replacement characteristics of gas under different structures and replacement conditions can be simulated and researched more accurately.

Description

Technical Field

[0001] The invention relates to the technical field of gas displacement characteristic test, and in particular to a pipeline gas displacement characteristic test system based on modular dead space. Background Art

[0002] In the fields of petrochemicals, hydrogen energy equipment, natural gas transportation, and environmental monitoring, small pipeline systems are widely used for gas transmission and processing. In these applications, the displacement efficiency, flow characteristics, and retention of gas in the pipeline have an important impact on the operational safety of the system. During the gas displacement process, the dead space area that may exist in the pipeline system will seriously affect the displacement efficiency, resulting in reduced production efficiency, waste of resources, and even potential safety hazards.

[0003] Dead space refers to the area in the pipeline where some gases flow slowly or almost stop during the gas replacement process. Since the gas is trapped in the dead space, it is difficult for the newly injected gas to effectively replace the original gas, thereby reducing the overall replacement efficiency. The existence of dead space not only affects the gas replacement efficiency, but also may lead to uneven composition of exported products and safety hazards of flammable, explosive and toxic gases.

[0004] Existing studies on gas displacement characteristics are mostly aimed at large-scale natural gas pipelines or long-distance natural gas transmission pipelines. For example, Chinese patent publication number CN118218334A discloses a purging device and method for LNG pipelines, including a purging pipeline connected to the inlet pipeline of a high-pressure pump and related regulating valves; Chinese patent publication number CN208662011U discloses a nitrogen purging structure for tank truck loading and unloading pipelines. However, traditional studies on gas displacement characteristics mostly use pipelines with specific structures or simple experimental devices for testing. These test devices are usually unable to obtain the changes in gas concentration in complex dead space structures under actual working conditions, and therefore it is difficult to derive the dead space gas displacement law. For different optimization forms of dead space, it is difficult for traditional fixed pipeline testing systems to quickly compare the displacement efficiency of different dead space structures. Summary of the invention

[0005] The present invention solves the problem that traditional gas displacement characteristic testing devices cannot obtain the gas concentration changes in complex dead space structures under actual working conditions, and thus it is difficult to derive the dead space gas displacement law. A pipeline gas displacement characteristic test system based on modular dead space is proposed to more accurately simulate and study the displacement characteristics of gas under different structures and displacement conditions.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a pipeline gas displacement characteristic test system based on modular dead space, comprising an air source component, wherein the air source component is connected to an air supply pipeline through a pipeline, and the air supply pipeline is connected to a dead space pipeline to be tested and an exhaust pipeline in turn, a flow control unit and a temperature control unit are respectively arranged between the air source component and the air supply pipeline, the end of the dead space pipeline to be tested is connected to a measuring module, and the exhaust pipeline is connected to a pressure control unit.

[0007] The present application proposes a pipeline gas displacement characteristic test system based on modular dead space, which can measure the gas displacement characteristics of the dead space pipeline under different displacement gases, displacement modes, gas pressures, and gas temperatures, and realize the testing and optimization of the dead space pipeline structure.

[0008] The present invention is further configured as follows: the gas source assembly includes a background gas high-pressure gas cylinder and a replacement gas high-pressure gas cylinder, the outlet of the background gas high-pressure gas cylinder is connected to a background gas regulating valve and a background gas cylinder pressure gauge; the outlet of the replacement gas high-pressure gas cylinder is connected to a replacement gas regulating valve and a replacement gas cylinder pressure gauge.

[0009] In this technical solution, the background gas high-pressure gas cylinder provides background gas for the entire replacement pipeline, and the replacement gas high-pressure gas cylinder provides replacement gas for the entire replacement pipeline. The gas supply pressure of the background gas high-pressure gas cylinder is monitored and controlled by the background gas cylinder pressure gauge and the background gas regulating valve; the gas supply pressure of the replacement gas high-pressure gas cylinder is monitored and controlled by the replacement gas cylinder pressure gauge and the replacement gas regulating valve.

[0010] The present invention is further configured as follows: the dead space pipeline to be measured includes a first pipeline connected to the air supply pipeline flange and a third pipeline connected to the exhaust pipeline flange, a second pipeline is arranged at the intersection of the first pipeline and the third pipeline, and the end of the second pipeline is connected to the measurement module.

[0011] In this technical solution, the dead cavity pipeline to be measured presents a modular setting, which is convenient for replacement and debugging; the easily disassembled dead cavity pipeline block to be measured can realize the rapid replacement of the dead cavity structure, thereby adjusting the parameters of the dead cavity length, dead cavity diameter, axial angle and circumferential angle.

[0012] The present invention is further configured as follows: the flow control unit includes a flow regulating valve and a gas flow meter connected to the flow regulating valve, and the opening of the flow regulating valve is regulated by feedback from the gas flow meter to control the pipeline flow.

[0013] In this technical solution, the flow regulating valve and the gas flow meter can monitor and control the gas supply flow rate.

[0014] The present invention is further configured as follows: the temperature control unit includes a three-way regulating valve, which is connected to a liquid tank and a temperature sensor in sequence, and controls the temperature of the heat exchange medium in the liquid tank and adjusts the opening of the three-way regulating valve using temperature sensor feedback to control the temperature of the gas medium.

[0015] In this technical solution, the gas is divided into two paths after passing through the three-way regulating valve. One path enters the liquid tank, and its outlet temperature is the temperature of the liquid tank, and is mixed with the other path. By adjusting the opening of the three-way regulating valve, the ratio of the two gases is controlled to achieve gas temperature control.

[0016] The present invention is further configured as follows: the temperature control unit includes an electric heater and a temperature sensor connected to the electric heater, the gas temperature is detected by the temperature sensor, and the power supply of the electric heater is feedback-controlled to control the temperature of the gas medium.

[0017] In the present technical solution, the temperature control unit may also be in the form of a combination of an electric heater and a temperature sensor.

[0018] The present invention is further configured as follows: the measurement module includes a gas chromatograph, the gas chromatograph is further connected to a control platform, and the gas chromatograph can transmit the measurement result to the control platform.

[0019] In this technical solution, the gas concentration at the end of the dead space is measured by a gas chromatograph and the result is transmitted to the control platform for recording.

[0020] The present invention is further configured as follows: the pressure control unit includes a pressure sensor, the pressure sensor is connected to a pressure regulating valve, the other end of the pressure regulating valve is respectively connected to a first stop valve and a second stop valve, and the other end of the second stop valve is connected to a vacuum pump.

[0021] In this technical solution, the pressure sensor feedback is used to adjust the opening of the pressure regulating valve, thereby controlling the pressure in the dead cavity pipeline to be measured, and the replacement mode of the dead cavity pipeline to be measured is controlled by the stop valve, the stop valve and the vacuum pump.

[0022] The present invention is further configured such that: the dead space pipeline to be measured is fixedly connected to a sampling port of a gas chromatograph.

[0023] In the technical solution, the end of the dead cavity pipeline to be measured and the sampling port of the gas chromatograph can be connected by threaded connection, flange connection, welding, groove connection, ferrule connection or compression connection.

[0024] The second pipeline includes a main pipeline and a secondary pipeline fixedly connected to the main pipeline, and the main pipeline and the secondary pipeline are arranged to intersect.

[0025] In the present technical solution, the dead space pipeline to be measured may not only be a primary dead space structure, but may also be a secondary dead space structure including a main pipeline and a secondary pipeline.

[0026] The present invention can bring the following beneficial effects: 1. The pipeline gas replacement characteristic test system proposed in the present invention can measure the gas replacement characteristics of the dead space pipeline under different replacement gases, replacement modes, gas pressures, and gas temperatures, and realize the testing and optimization of the dead space pipeline structure; 2. The present invention proposes a modular dead space pipeline structure that is easy to replace and debug, which is convenient for quickly adjusting and replacing the dead space pipeline structure in a pipeline gas displacement characteristic test system. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of an implementation of a pipeline gas displacement characteristics test system based on modular dead space in the present application.

[0028] Figure 2 It is a schematic diagram of another implementation of a pipeline gas displacement characteristics test system based on modular dead space in the present application.

[0029] Figure 3 This is a schematic diagram of dead space pipelines at different circumferential angles of a pipeline gas displacement characteristics test system based on modular dead space in the present application.

[0030] Figure 4 This is a schematic diagram of dead space pipelines at different axial angles of a pipeline gas displacement characteristics test system based on modular dead space in the present application.

[0031] Figure 5 It is a structural schematic diagram of a secondary dead space pipeline of a pipeline gas displacement characteristics test system based on modular dead space in the present application.

[0032] Reference numerals: Background gas high-pressure gas cylinder 1, background gas regulating valve 2, background gas cylinder pressure gauge 3, replacement gas high-pressure gas cylinder 4, replacement gas regulating valve 5, replacement gas cylinder pressure gauge 6, flow regulating valve 7, gas flow meter 8, three-way regulating valve 9, liquid tank 10, temperature sensor 11, gas supply pipeline 12, measured dead cavity pipeline 13, gas chromatograph 14, control platform 15, exhaust pipeline 16, pressure sensor 17, pressure regulating valve 18, stop valve 19, stop valve 20, vacuum pump 21, first pipeline 131, second pipeline 132, third pipeline 133, main pipeline 1321, and auxiliary pipeline 1322. DETAILED DESCRIPTION

[0033] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific implementation method described herein is only an optimal embodiment of the present invention, which is only used to explain the present invention and does not limit the scope of protection of the present invention. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0034] Example 1 This embodiment proposes a pipeline gas displacement characteristic test system based on modular dead space, which can flexibly adjust the dead space pipeline structure to more accurately simulate and study the displacement characteristics of gas under different structures and displacement conditions. Modular design can not only realize the efficient configuration of the test system, but also effectively reduce the test cost and meet the test needs of different industries and application scenarios.

[0035] refer to Figure 1 and Figure 2 The pipeline gas displacement characteristic test system of this embodiment mainly includes a gas source component, a gas supply pipeline 12, a dead space pipeline to be tested 13, an exhaust pipeline 16, a flow control unit, a temperature control unit, a measurement module and a pressure control unit.

[0036] The gas source assembly is specifically connected to one end of the gas supply pipe 12 through a pipe, the other end of the gas supply pipe 12 is connected to one end of the dead space pipe 13 to be measured, the other end of the dead space pipe 13 to be measured is connected to one end of the exhaust pipe 16, the other end of the exhaust pipe 16 is connected to the pressure control unit, and a flow control unit and a temperature control unit are sequentially arranged between the gas source assembly and the gas supply pipe 12; in addition, the end of the dead space pipe 13 to be measured is connected to the measurement module.

[0037] In this embodiment, the air supply pipeline 12, the measured dead space pipeline 13 and the exhaust pipeline 16 can adopt vacuum pipelines or other heat insulation measures to reduce the temperature change inside the pipelines during the replacement process.

[0038] refer to Figure 1 The gas source component mainly includes a background gas high-pressure gas cylinder 1 and a replacement gas high-pressure gas cylinder 4. The outlet of the background gas high-pressure gas cylinder 1 is connected to the inlet of the background gas regulating valve 2, and the outlet of the background gas regulating valve 2 is connected to the background gas cylinder pressure gauge 3; the outlet of the replacement gas high-pressure gas cylinder 4 is connected to the inlet of the replacement gas regulating valve 5, and the outlet of the replacement gas regulating valve 5 is connected to the replacement gas cylinder pressure gauge 6.

[0039] The outlet of the background gas regulating valve 2 and the outlet of the replacement gas regulating valve 5 are both connected to the flow control unit.

[0040] In the above technical scheme, the background gas high-pressure gas cylinder 1 provides background gas for the entire replacement pipeline, and the replacement gas high-pressure gas cylinder 4 provides replacement gas for the entire replacement pipeline. The gas supply pressure of the background gas high-pressure gas cylinder 1 is monitored and controlled by the background gas cylinder pressure gauge 3 and the background gas regulating valve 2; the gas supply pressure of the replacement gas high-pressure gas cylinder 4 is monitored and controlled by the replacement gas cylinder pressure gauge 6 and the replacement gas regulating valve 5.

[0041] For the above-mentioned dead space pipeline 13 to be tested, refer to Figure 3 , which mainly includes a first pipeline 131, a second pipeline 132 and a third pipeline 133. In this embodiment, one end of the first pipeline 131 is connected to the air supply pipeline 12 through a flange, one end of the third pipeline 133 is connected to the exhaust pipeline 16 through a flange, and a second pipeline 132 is arranged at the intersection of the first pipeline 131 and the third pipeline 132, and the end of the second pipeline 132 is connected to the measurement module.

[0042] In the above technical solution, the dead space pipe 13 to be measured presents a modular setting, which is convenient for replacement and debugging; the easily disassembled dead space pipe block to be measured can realize the rapid replacement of the dead space structure, thereby adjusting the parameters of the dead space length, dead space diameter, axial angle and circumferential angle.

[0043] refer to Figure 1 The flow control unit mainly includes a flow regulating valve 7 and a gas flow meter 8. The flow regulating valve 7 is connected to the gas flow meter 8. The opening of the flow regulating valve 7 is adjusted through feedback from the gas flow meter 8 to achieve pipeline flow control.

[0044] In the above technical solution, the flow regulating valve and the gas flow meter can monitor and control the gas supply flow rate.

[0045] The temperature control unit mainly includes a three-way regulating valve 9, a liquid tank 10 and a temperature sensor 11. One outlet of the three-way regulating valve 9 is connected to the liquid tank 10, and the other outlet of the three-way regulating valve 9 is directly connected to the gas supply pipeline 12. One side of the liquid tank 10 is connected to the temperature sensor 11; by controlling the temperature of the heat exchange medium in the liquid tank 10, the opening of the three-way regulating valve 9 is adjusted according to the feedback from the sensor 11 to achieve the control of the temperature of the gas medium.

[0046] In the above technical solution, the gas is divided into two paths after passing through the three-way regulating valve 9. One path enters the liquid tank 10, and its outlet temperature is the temperature of the liquid tank 10, and is mixed with the other path. By adjusting the opening of the three-way regulating valve 9, the ratio of the two gases is controlled to achieve gas temperature control.

[0047] For measurement modules, refer to Figure 1, which mainly includes a gas chromatograph 14 and a control platform 15 . The gas chromatograph 14 can be connected to the control platform 15 . After completing the measurement, the gas chromatograph 14 transmits the measurement result to the control platform 15 .

[0048] In the above technical solution, the gas concentration at the end of the dead space is measured by the gas chromatograph 14 and the result is transmitted to the control platform 15 for recording.

[0049] The pressure control unit mainly includes a pressure sensor 17, a pressure regulating valve 18, a first stop valve 19, a second stop valve 20 and a vacuum pump 21. The pressure sensor 17 is connected to one end of the pressure regulating valve 18, and the other end of the pressure regulating valve 18 is respectively connected to one end of the first stop valve 19 and one end of the second stop valve 20, and the other end of the second stop valve 20 is connected to the vacuum pump 21.

[0050] In the above technical solution, the pressure sensor 17 is used to feedback and adjust the opening of the pressure regulating valve 18, thereby controlling the pressure in the dead space pipeline 13 to be measured, and the replacement mode of the dead space pipeline to be measured is controlled by the stop valve 19, the stop valve 20 and the vacuum pump 21; for example, the continuous purge replacement, inflation and emptying replacement and vacuum replacement mentioned in the subsequent embodiments.

[0051] More specifically, the dead space pipe 13 to be tested is fixedly connected to the sampling port of the gas chromatograph 14. In this technical solution, the end of the dead space pipe 13 to be tested and the sampling port of the gas chromatograph 14 can be connected by thread, flange, welding, groove, ferrule or compression.

[0052] refer to Figure 3 , a and b are schematic diagrams of the dead space pipeline 13 to be measured with different circumferential angles, that is, the circumferential angles of the second pipeline 132 of the dead space pipeline 13 to be measured in a and b are different relative to the first pipeline 131 or the third pipeline 133.

[0053] refer to Figure 4 , c and d are schematic diagrams of the dead space pipeline 13 to be measured with different axial angles, that is, the axial angles of the second pipeline 132 of the dead space pipeline 13 to be measured in c and d are different relative to the first pipeline 131 or the third pipeline 133.

[0054] refer to Figure 5 The second pipeline 132 includes a main pipeline 1321 and a secondary pipeline 1322 fixedly connected to the main pipeline 1321, and the main pipeline 1321 and the secondary pipeline 1322 are arranged to intersect.

[0055] In the above technical solution, the dead space pipeline to be measured may not only be a primary dead space structure, but also a secondary dead space structure including a main pipeline and a secondary pipeline. Figure 5Figures e, f and g list three different secondary dead space structures including a main pipe and a secondary pipe.

[0056] Example 2 This embodiment proposes a pipeline gas displacement characteristic test system based on modular dead space, which can flexibly adjust the dead space pipeline structure to more accurately simulate and study the displacement characteristics of gas under different structures and displacement conditions. Modular design can not only realize the efficient configuration of the test system, but also effectively reduce the test cost and meet the test needs of different industries and application scenarios.

[0057] refer to Figure 1 and Figure 2 The pipeline gas displacement characteristic test system of this embodiment mainly includes a gas source component, a gas supply pipeline 12, a dead space pipeline to be tested 13, an exhaust pipeline 16, a flow control unit, a temperature control unit, a measurement module and a pressure control unit.

[0058] The gas source assembly is specifically connected to one end of the gas supply pipe 12 through a pipe, the other end of the gas supply pipe 12 is connected to one end of the dead space pipe 13 to be measured, the other end of the dead space pipe 13 to be measured is connected to one end of the exhaust pipe 16, the other end of the exhaust pipe 16 is connected to the pressure control unit, and a flow control unit and a temperature control unit are sequentially arranged between the gas source assembly and the gas supply pipe 12; in addition, the end of the dead space pipe 13 to be measured is connected to the measurement module.

[0059] refer to Figure 1 The gas source component mainly includes a background gas high-pressure gas cylinder 1 and a replacement gas high-pressure gas cylinder 4. The outlet of the background gas high-pressure gas cylinder 1 is connected to the inlet of the background gas regulating valve 2, and the outlet of the background gas regulating valve 2 is connected to the background gas cylinder pressure gauge 3; the outlet of the replacement gas high-pressure gas cylinder 4 is connected to the inlet of the replacement gas regulating valve 5, and the outlet of the replacement gas regulating valve 5 is connected to the replacement gas cylinder pressure gauge 6.

[0060] The outlet of the background gas regulating valve 2 and the outlet of the replacement gas regulating valve 5 are both connected to the flow control unit.

[0061] In the above technical scheme, the background gas high-pressure gas cylinder 1 provides background gas for the entire replacement pipeline, and the replacement gas high-pressure gas cylinder 4 provides replacement gas for the entire replacement pipeline. The gas supply pressure of the background gas high-pressure gas cylinder 1 is monitored and controlled by the background gas cylinder pressure gauge 3 and the background gas regulating valve 2; the gas supply pressure of the replacement gas high-pressure gas cylinder 4 is monitored and controlled by the replacement gas cylinder pressure gauge 6 and the replacement gas regulating valve 5.

[0062] For the above-mentioned dead space pipeline 13 to be tested, refer to Figure 3, which mainly includes a first pipeline 131, a second pipeline 132 and a third pipeline 133. In this embodiment, one end of the first pipeline 131 is connected to the air supply pipeline 12 through a flange, one end of the third pipeline 133 is connected to the exhaust pipeline 16 through a flange, and a second pipeline 132 is arranged at the intersection of the first pipeline 131 and the third pipeline 132, and the end of the second pipeline 132 is connected to the measurement module.

[0063] In the above technical solution, the dead space pipe 13 to be measured presents a modular setting, which is convenient for replacement and debugging; the easily disassembled dead space pipe block to be measured can realize the rapid replacement of the dead space structure, thereby adjusting the parameters of the dead space length, dead space diameter, axial angle and circumferential angle.

[0064] refer to Figure 1 The flow control unit mainly includes a flow regulating valve 7 and a gas flow meter 8. The flow regulating valve 7 is connected to the gas flow meter 8. The opening of the flow regulating valve 7 is adjusted through feedback from the gas flow meter 8 to achieve pipeline flow control.

[0065] In the above technical solution, the flow regulating valve and the gas flow meter can monitor and control the gas supply flow rate.

[0066] The measurement module mainly includes a gas chromatograph 14 and a control platform 15 . The gas chromatograph 14 can be connected to the control platform 15 . After completing the measurement, the gas chromatograph 14 transmits the measurement result to the control platform 15 .

[0067] In the above technical solution, the gas concentration at the end of the dead space is measured by the gas chromatograph 14 and the result is transmitted to the control platform 15 for recording.

[0068] The pressure control unit mainly includes a pressure sensor 17, a pressure regulating valve 18, a first stop valve 19, a second stop valve 20 and a vacuum pump 21. The pressure sensor 17 is connected to one end of the pressure regulating valve 18, and the other end of the pressure regulating valve 18 is respectively connected to one end of the first stop valve 19 and one end of the second stop valve 20, and the other end of the second stop valve 20 is connected to the vacuum pump 21.

[0069] In the above technical solution, the pressure sensor 17 is used to feedback and adjust the opening of the pressure regulating valve 18, thereby controlling the pressure in the dead space pipeline 13 to be measured, and the replacement mode of the dead space pipeline to be measured is controlled by the stop valve 19, the stop valve 20 and the vacuum pump 21; for example, continuous purge replacement, inflation and emptying replacement and vacuum replacement.

[0070] More specifically, the dead space pipe 13 to be tested is fixedly connected to the sampling port of the gas chromatograph 14. In this technical solution, the end of the dead space pipe 13 to be tested and the sampling port of the gas chromatograph 14 can be connected by thread, flange, welding, groove, ferrule or compression.

[0071] refer to Figure 5 The second pipeline 132 includes a main pipeline 1321 and a secondary pipeline 1322 fixedly connected to the main pipeline 1321, and the main pipeline 1321 and the secondary pipeline 1322 are arranged to intersect.

[0072] refer to Figure 2 , which is different from Example 1 in that the temperature control unit of this embodiment mainly includes an electric heater 22 and a temperature sensor 11. The electric heater 22 is connected to the temperature sensor 11, and the gas temperature is detected by the temperature sensor 11, and the power supply of the electric heater 10 is feedback-controlled, thereby finally realizing the temperature control of the gas medium.

[0073] In the present technical solution, the temperature control unit may also be in the form of a combination of an electric heater and a temperature sensor.

[0074] In addition, in addition to the temperature control methods described in this embodiment and embodiment 1, other heat exchange methods can also be used to adjust the temperature of the gas medium, which are not listed here one by one.

[0075] Example 3 refer to Figure 1 Based on the above-mentioned embodiment 1, the above-mentioned pipeline gas replacement characteristic test system can perform background gas replacement of the dead space pipeline. During the background gas replacement process, the tested pipeline is replaced with the background atmosphere according to the background gas provided by the background gas high-pressure gas cylinder 1.

[0076] During the background gas replacement process, the first stop valve 19 is opened and the second stop valve 20 is closed. The background gas high-pressure cylinder 1 can provide background gas for the entire replacement pipeline system, and its supply pressure is monitored and controlled by the background gas cylinder pressure gauge 3 and the background gas regulating valve 2. The supply flow of the background gas is monitored and controlled by the flow regulating valve 7 and the gas flow meter 8. The supply temperature is monitored by the temperature sensor 11. The background gas is divided into two paths by the three-way regulating valve 9. One path enters the liquid tank 10, and its outlet temperature is the temperature of the liquid tank 10, and is mixed with the other path. By adjusting the opening of the three-way regulating valve 9, the ratio of the two gases is controlled to achieve the control of the background gas temperature.

[0077] The liquid tank 10 is filled with liquid at room temperature, low temperature or high temperature to achieve a relatively stable temperature environment.

[0078] Subsequently, the background gas enters the gas supply pipeline 12 to supply gas to the pipeline system. The background gas supply pressure is monitored and controlled by the pressure sensor 17 and the pressure regulating valve 18 connected to the exhaust pipeline 16. When the background gas concentration sampled and detected by the gas chromatograph 14 reaches the set background atmosphere required concentration, the background gas replacement process ends.

[0079] Example 4 refer to Figure 1 The pipeline gas replacement characteristic test system based on modular dead space in this embodiment can also perform continuous purge replacement.

[0080] In the continuous purge and replacement characteristic test of pipeline gas, the replacement gas provided by the replacement gas high-pressure gas cylinder 4 is used to continuously purge and replace the dead space pipeline 13 to be tested. The replacement gas high-pressure gas cylinder 4 can provide replacement gas for the entire replacement pipeline system, and the control method of its gas supply temperature, pressure and flow rate is the same as that of the background gas in Example 3.

[0081] The replacement gas enters the gas supply pipeline 12 to supply gas to the pipeline system. The gas supply pressure is monitored and controlled by the pressure sensor 17 and the pressure regulating valve 18 connected to the exhaust pipeline 16. The replacement gas flow is rectified in the gas supply pipeline 12 and achieves stable flow, and enters the dead space pipeline 13 to be measured for replacement. The background gas concentration and replacement gas concentration at the end of the dead space pipeline 13 to be measured are sampled and detected by the gas chromatograph 14 and the control platform 15.

[0082] In the continuous purge replacement characteristic test, the first stop valve 19 is opened, and the replacement gas is discharged from the system through the exhaust pipe. When the background gas concentration sampled and detected by the gas chromatograph 14 is less than the set replacement required concentration, the replacement process ends.

[0083] Example 5 refer to Figure 1 The pipeline gas replacement characteristic test system based on modular dead space in this embodiment can also perform continuous inflation and emptying replacement.

[0084] In the pipeline gas inflation, emptying and replacement characteristics test, the control of replacement gas flow rate, temperature and pressure is the same as in Example 4.

[0085] During the inflation and emptying process, the first stop valve 19 and the second stop valve 20 are closed, and the dead space pipeline 13 to be measured is raised to a higher pressure by the replacement gas provided by the replacement gas high-pressure gas cylinder 4. Subsequently, the first stop valve 19 is opened to discharge the high-pressure mixed gas.

[0086] The inflation and evacuation process is cyclically continued until the background gas concentration detected by the gas chromatograph 14 is less than the set replacement required concentration, and then the inflation, evacuation and replacement process is completed.

[0087] Example 6 refer to Figure 2 The pipeline gas replacement characteristic test system based on modular dead space in this embodiment can also perform high-temperature gas replacement. During the high-temperature gas replacement process, the control of the replacement gas flow rate and pressure is the same as in Example 4. The replacement gas is heated by the electric heater 22, and the gas supply temperature is achieved by the temperature sensor 11 monitoring the replacement gas temperature and then controlling the power output of the electric heater 22, thereby achieving high-temperature gas purge replacement of the dead space pipeline.

[0088] Example 7 refer to Figure 1 The pipeline gas replacement characteristic test system based on modular dead space in this embodiment can also perform vacuum replacement.

[0089] In the pipeline gas vacuum replacement characteristic test, the control of replacement gas flow rate, temperature and pressure is the same as in Example 4.

[0090] During the vacuum replacement process, the first stop valve 19 is closed, the second stop valve 20 is opened, and the dead space pipeline 13 to be tested is evacuated using the vacuum pump 21. Subsequently, the second stop valve 20 and the vacuum pump 21 are closed, and the dead space pipeline 13 to be tested is raised to a higher pressure using the replacement gas provided by the replacement gas high-pressure gas cylinder 4.

[0091] The inflation and vacuuming process is circulated until the background gas concentration detected by the gas chromatograph 14 is less than the set replacement required concentration, and then the vacuuming replacement process is completed.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention is described in detail with reference to the embodiments, it should be understood by those skilled in the art that any modification or equivalent replacement of the technical solutions of the present invention does not depart from the spirit and scope of the technical solutions of the present invention and should be included in the scope of the claims of the present invention.

Claims

1. A pipeline gas displacement characteristics test system based on modular dead space, characterized in that: The invention comprises an air source component, wherein the air source component is connected to an air supply pipeline (12) via a pipeline, the air supply pipeline (12) is connected in sequence to a dead space pipeline (13) to be measured and an exhaust pipeline (16), a flow control unit and a temperature control unit are respectively arranged between the air source component and the air supply pipeline (12), the end of the dead space pipeline (13) to be measured is connected to a measuring module, and the exhaust pipeline (16) is connected to a pressure control unit.

2. According to claim 1, a pipeline gas displacement characteristic test system based on modular dead space is characterized in that: The gas source assembly comprises a background gas high-pressure gas cylinder (1) and a replacement gas high-pressure gas cylinder (4); the outlet of the background gas high-pressure gas cylinder (1) is connected to a background gas regulating valve (2) and a background gas cylinder pressure gauge (3); the outlet of the replacement gas high-pressure gas cylinder (4) is connected to a replacement gas regulating valve (5) and a replacement gas cylinder pressure gauge (6).

3. A pipeline gas displacement characteristic test system based on modular dead space according to claim 1 or 2, characterized in that: The dead space pipeline (13) to be measured comprises a first pipeline (131) flange-connected to the air supply pipeline (12) and a third pipeline (133) flange-connected to the exhaust pipeline (16); a second pipeline (132) is arranged at the intersection of the first pipeline (131) and the third pipeline (133); and a terminal end of the second pipeline (132) is connected to a measurement module.

4. According to the modular dead space-based pipeline gas displacement characteristic test system of claim 1, it is characterized in that: The flow control unit comprises a flow regulating valve (7) and a gas flow meter (8) connected to the flow regulating valve (7), and the opening of the flow regulating valve (7) is regulated by feedback from the gas flow meter (8) to control the pipeline flow.

5. A pipeline gas displacement characteristic test system based on modular dead space according to claim 1 or 4, characterized in that: The temperature control unit comprises a three-way regulating valve (9), which is sequentially connected to a liquid tank (10) and a temperature sensor (11). The temperature of the gas medium is controlled by controlling the temperature of the heat exchange medium in the liquid tank (10) and adjusting the opening of the three-way regulating valve (9) by feedback from the temperature sensor (11).

6. A pipeline gas displacement characteristic test system based on modular dead space according to claim 1 or 4, characterized in that: The temperature control unit comprises an electric heater (22) and a temperature sensor (11) connected to the electric heater (22), and detects the temperature of the gas through the temperature sensor (11), and feedback controls the power supply of the electric heater (10) to control the temperature of the gas medium.

7. A pipeline gas displacement characteristic test system based on modular dead space according to claim 1 or 2, characterized in that: The measurement module comprises a gas chromatograph (14), the gas chromatograph (14) is further connected to a control platform (15), and the gas chromatograph (14) is capable of transmitting measurement results to the control platform (15).

8. A pipeline gas displacement characteristic test system based on modular dead space according to claim 1, 2 or 4, characterized in that: The pressure control unit comprises a pressure sensor (17), the pressure sensor (17) is connected to a pressure regulating valve (18), the other end of the pressure regulating valve (18) is respectively connected to a first stop valve (19) and a second stop valve (20), and the other end of the second stop valve (20) is connected to a vacuum pump (21).

9. The pipeline gas displacement characteristic test system based on modular dead space according to claim 7 is characterized in that: The dead space pipeline (13) to be measured is specifically fixedly connected to a sampling port of a gas chromatograph (14).

10. The pipeline gas displacement characteristic test system based on modular dead space according to claim 3 is characterized in that: The second pipeline (132) comprises a main pipeline (1321) and a secondary pipeline (1322) fixedly connected to the main pipeline (1321), and the main pipeline (1321) and the secondary pipeline (1322) are arranged to intersect.

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