Compressor purge gas recovery system and method of use thereof

Abstract

The present application belongs to the technical field of vent gas recovery, and relates to a compressor vent gas recovery system and a use method thereof. The present application comprises a compressor interface pipeline; the pressure in the compressor interface pipeline and a buffer tank is monitored in real time through a pipeline pressure transmitter and a buffer tank pressure transmitter; in an emergency, a first emergency vent valve is opened, gas is safely discharged into a flare system through a flare interface pipeline; a primary recovery interface pipeline is conducive to the preliminary recovery and reuse of residual process gas; the residual process gas is introduced into the buffer tank for storage, which can balance the system pressure; the buffer tank is connected to a secondary recovery interface pipeline through a third remote on-off valve, and the residual process gas in the buffer tank is subjected to more in-depth treatment and recovery; when the gas pressure in the buffer tank is too high, a second emergency vent valve is opened, gas is safely discharged into the flare system through the flare interface pipeline; through a control system, the running state of the entire system can be remotely monitored and controlled.

Description

Technical Field

[0001] This invention belongs to the field of air venting recovery technology, and relates to a compressor air venting recovery system and its usage method. Background Technology

[0002] Compressors, as key pieces of equipment, play a crucial role in industries such as petroleum and chemical engineering. They are primarily used to pressurize process gases to ensure the smooth operation of production processes. However, when a compressor is shut down, the residual process gases inside must typically be safely released.

[0003] Currently, most common methods for venting residual process gas from compressors on the market involve directly discharging the residual process gas into a flare for combustion. While this approach is simple and direct, it has several drawbacks.

[0004] First, current methods lack effective control over compressor venting, potentially leading to instability and safety issues in the gas release process. Second, the lack of monitoring mechanisms prevents real-time understanding of compressor venting pressure, increasing potential risks during venting. Furthermore, this direct emission method results in the waste of significant recyclable resources. Process gases often contain energy and valuable components; direct combustion not only fails to recover these resources but also pollutes the environment.

[0005] In summary, existing methods for venting residual process gas from compressors have several drawbacks, including the inability to accurately control the release of vented air, the inability to monitor the vented air pressure, and the resulting waste of residual process gas. Summary of the Invention

[0006] The purpose of this invention is to provide a compressor venting air recovery system and its usage method to solve the technical problems of existing compressor residual process gas venting methods, which cannot accurately control compressor venting air release, cannot monitor compressor venting air pressure, and result in residual process gas waste. This invention can detect and accurately control the venting and discharge process of residual process gas in real time, and realize the effective recovery and utilization of residual process gas.

[0007] To achieve the above objectives, the present invention employs the following technical solution: This invention discloses a compressor vent air recovery system, including compressor interface pipelines; The compressor interface pipeline is connected to the flare interface pipeline through the first emergency vent valve, the compressor interface pipeline is connected to the buffer tank through the first remote switch valve, and the compressor interface pipeline is connected to the primary recovery interface pipeline through the second remote switch valve. The buffer tank is connected to the flare interface pipeline via a second emergency vent valve, and the buffer tank is connected to the secondary recovery interface pipeline via a third remote switching valve. A pipeline pressure transmitter is installed on the compressor interface pipeline, and the pipeline pressure transmitter is electrically connected to the first emergency vent valve. A buffer tank pressure transmitter is installed on the buffer tank, and the buffer tank pressure transmitter is electrically connected to the third remote switching valve. The first emergency vent valve, the second emergency vent valve, the first remote switching valve, the second remote switching valve, the third remote switching valve, the pipeline pressure transmitter, and the buffer tank pressure transmitter are all connected to the control system.

[0008] Furthermore, the control system includes a SIS safety instrumented system and a DCS distributed control system; The SIS safety instrumented system is connected to the first emergency vent valve, the second emergency vent valve, the pipeline pressure transmitter, and the buffer tank pressure transmitter, respectively. The DCS distributed control system is connected to the first remote switching valve, the second remote switching valve, the third remote switching valve, the pipeline pressure transmitter, and the buffer tank pressure transmitter, respectively.

[0009] Furthermore, the pipeline pressure transmitter includes a first pressure transmitter, which is located between the compressor interface pipeline and the first emergency vent valve, and the first pressure transmitter is electrically connected to the first emergency vent valve. The buffer tank pressure transmitter includes a second pressure transmitter, which is electrically connected to a second emergency vent valve. Both the first and second pressure transmitters are connected to the SIS safety instrumented system.

[0010] Furthermore, the pipeline pressure transmitter includes a third pressure transmitter, which is located between the compressor interface pipeline and the second remote switching valve, and is electrically connected to the first remote switching valve. The buffer tank pressure transmitter includes a fourth pressure transmitter, which is connected to a third remote switching valve. Both the third and fourth pressure transmitters are connected to the DCS distributed control system.

[0011] Furthermore, the secondary recovery interface pipeline is equipped with a first regulating valve and a fifth pressure transmitter. The first regulating valve is located between the third remote switching valve and the fifth pressure transmitter. The first regulating valve and the fifth pressure transmitter are electrically connected to the control system.

[0012] Furthermore, the buffer tank is connected to the three-stage recovery interface pipeline via a fourth remote switching valve, which is electrically connected to both the control system and the buffer tank pressure transmitter.

[0013] Furthermore, the three-stage recovery interface pipeline is equipped with a second regulating valve and a sixth pressure transmitter. The second regulating valve is located between the fourth remote switching valve and the sixth pressure transmitter, and the second regulating valve and the sixth pressure transmitter are electrically connected to the control system.

[0014] Furthermore, the buffer tank is equipped with a level transmitter, which is electrically connected to the control system.

[0015] Furthermore, a second check valve is provided on the primary recycling interface pipeline.

[0016] Based on the above method, the present invention also discloses a method for using a compressor vent air recovery system, comprising the following steps: The pressure in the compressor interface pipeline is obtained in real time through the pipeline pressure transmitter, and the pressure in the buffer tank is obtained in real time through the buffer tank pressure transmitter. When the pressure in the compressor interface pipeline is greater than or equal to the first threshold pressure, the control system closes the second emergency vent valve, the first remote switching valve and the second remote switching valve, and opens the first emergency vent valve. The residual process gas of the compressor is discharged to the flare for combustion treatment through the first emergency vent valve and the flare interface pipeline. When the pressure in the compressor interface pipeline is greater than or equal to the second threshold pressure and less than the first threshold pressure, the control system activates the pipeline pressure transmitter alarm. When the pressure in the compressor interface pipeline is greater than or equal to the third threshold pressure and less than the second threshold pressure, the control system closes the first emergency vent valve and the first remote switching valve, and opens the second remote switching valve. The residual process gas of the compressor is discharged and recovered through the second remote switching valve and the first-stage recovery interface pipeline. When the pressure in the compressor interface pipeline is greater than or equal to the fourth threshold pressure and less than the third threshold pressure, the control system closes the first emergency vent valve, the second emergency vent valve and the second remote switching valve, and opens the first remote switching valve. The residual process gas of the compressor is discharged into the buffer tank through the first remote switching valve. When the pressure in the buffer tank is greater than or equal to the fifth threshold pressure, the control system closes the first emergency vent valve, the first remote switching valve and the third remote switching valve, and opens the second emergency vent valve. The residual process gas of the compressor is discharged to the flare for combustion treatment through the second emergency vent valve and the flare interface pipeline. When the pressure inside the buffer tank is greater than or equal to the sixth threshold pressure and less than the fifth threshold pressure, the buffer tank pressure transmitter is activated to trigger an alarm. When the pressure inside the buffer tank is greater than or equal to the seventh threshold pressure and less than the sixth threshold pressure, the control system closes the second emergency vent valve and opens the third remote switching valve. The residual process gas from the compressor is discharged and recovered through the third remote switching valve and the secondary recovery interface pipeline.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention includes a compressor interface pipeline for introducing residual process gas into the recovery system of this invention; the pressure in the compressor interface pipeline and the buffer tank is monitored in real time by pipeline pressure transmitters and buffer tank pressure transmitters; in an emergency, the first emergency vent valve is quickly opened to safely discharge the gas into the flare system for combustion through the flare interface pipeline, preventing gas leakage from causing environmental pollution or safety accidents; the compressor interface pipeline is connected to the primary recovery interface pipeline through a second remote switching valve, which is beneficial for the initial recovery and reuse of residual process gas; the residual process gas is introduced into the buffer tank for storage, so that it can be further processed or recovered when needed. In addition, the buffer tank serves as a gas... The system uses a buffer tank for storage and buffering, balancing system pressure and preventing damage from gas pressure fluctuations. The buffer tank is connected to a secondary recovery interface pipeline via a third remote switching valve for further processing and recovery of residual process gas. When the buffer tank pressure is too high, the second emergency vent valve is quickly opened, safely releasing the gas into the flare system for combustion via the flare interface pipeline. Furthermore, the first emergency vent valve, second emergency vent valve, first remote switching valve, second remote switching valve, pipeline pressure transmitter, and buffer tank pressure transmitter are all connected to a control system. Through this control system, operators can remotely monitor and control the entire system's operation, achieving automated and intelligent management. In short, this invention enables real-time detection and accurate control of the residual process gas venting process, achieving effective recovery and utilization of residual process gas.

[0018] 2. The first regulating valve of this invention is used to adjust the flow rate of the secondary recovery interface pipeline, and the fifth pressure transmitter is used to detect the pressure of the compressor inlet pipeline in the secondary recovery system. When the pressure of the compressor inlet pipeline in the secondary recovery system is greater than the threshold, the third remote switching valve is closed to ensure the safety of the system gas circuit.

[0019] 3. The buffer tank of the present invention is connected to a three-stage recovery interface pipeline through a fourth remote switching valve. The fourth remote switching valve is electrically connected to the control system and the pressure transmitter of the buffer tank. By adding a recovery interface pipeline, the purpose of graded recovery of residual process gas according to pressure is achieved, which is conducive to achieving more refined recovery and utilization of residual process gas.

[0020] 4. The buffer tank of the present invention is equipped with a level transmitter, which is electrically connected to the control system, so as to facilitate the real-time acquisition of the liquid level in the buffer tank and facilitate the precise control of the system.

[0021] 5. The method of this invention acquires the pressure in the compressor interface pipeline in real time through a pipeline pressure transmitter and the pressure in the buffer tank in real time through a buffer tank pressure transmitter. When the pressure in the compressor interface pipeline is greater than or equal to the first threshold pressure, the control system closes the second emergency vent valve, the first remote switching valve, and the second remote switching valve, and opens the first emergency vent valve. The residual process gas of the compressor is discharged to the flare for combustion treatment through the first emergency vent valve and the flare interface pipeline. When the pressure in the compressor interface pipeline is greater than or equal to the second threshold pressure and less than the first threshold pressure, the control system activates the pipeline pressure transmitter alarm. When the pressure in the compressor interface pipeline is greater than or equal to the third threshold pressure and less than the second threshold pressure, the control system closes the first emergency vent valve and the first remote switching valve, and opens the second remote switching valve. The residual process gas of the compressor is discharged and recovered through the second remote switching valve and the first-stage recovery interface pipeline. When the pressure in the compressor interface pipeline... When the pressure is greater than or equal to the fourth threshold pressure and less than the third threshold pressure, the control system closes the first emergency vent valve, the second emergency vent valve, and the second remote switching valve, and opens the first remote switching valve. The residual process gas from the compressor is discharged into the buffer tank through the first remote switching valve. When the pressure in the buffer tank is greater than or equal to the fifth threshold pressure, the control system closes the first emergency vent valve, the first remote switching valve, and the third remote switching valve, and opens the second emergency vent valve. The residual process gas from the compressor is discharged to the flare for combustion treatment through the second emergency vent valve and the flare interface pipeline. When the pressure in the buffer tank is greater than or equal to the sixth threshold pressure and less than the fifth threshold pressure, the control system activates the buffer tank pressure transmitter to trigger an alarm. When the pressure in the buffer tank is greater than or equal to the seventh threshold pressure and less than the sixth threshold pressure, the control system closes the second emergency vent valve and opens the third remote switching valve. The residual process gas from the compressor is discharged and recovered through the third remote switching valve and the secondary recovery interface pipeline. This invention enables real-time detection and accurate control of the residual process gas venting process, achieving effective recovery and utilization of the residual process gas. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a program logic diagram of the compressor air recovery system of the present invention; Figure 3 This is a flowchart of the method of the present invention.

[0023] The components include: 1. Compressor; 2. SIS Safety Instrumented System; 3. DCS Distributed Control System; 4. First Emergency Vent Valve; 5. First Pressure Transmitter; 6. Second Emergency Vent Valve; 7. Second Pressure Transmitter; 8. Third Pressure Transmitter; 9. First Remote Switch Valve; 10. First Check Valve; 11. Second Remote Switch Valve; 12. Second Check Valve; 13. Fourth Pressure Transmitter; 14. Third Remote Switch Valve; 15. Fourth Remote Switch Valve; 16. Level Transmitter; 17. First Control Valve; 18. Fifth Pressure Transmitter; 19. Second Control Valve; 20. Sixth Pressure Transmitter; 21. Buffer Tank; 22. Primary Recovery Interface Pipeline; 23. Compressor Interface Pipeline; 24. Flare Interface Pipeline; 25. Secondary Recovery Interface Pipeline; 26. Tertiary Recovery Interface Pipeline; 27. Pipeline Pressure Transmitter; 28. Buffer Tank Pressure Transmitter. Detailed Implementation

[0024] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0025] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0026] The present invention will now be described in further detail with reference to the accompanying drawings: See Figure 1 The present invention discloses a compressor vent gas recovery system, including a compressor interface line 23, which is used to introduce residual process gas into the recovery system of the present invention. The compressor interface line 23 is connected to the flare interface line 24 via the first emergency vent valve 4. In an emergency, the first emergency vent valve 4 can be quickly opened to safely discharge the gas into the flare system for combustion through the flare interface line 24, preventing gas leakage from causing environmental pollution or safety accidents. The compressor interface line 23 is connected to the buffer tank 21 via the first remote switching valve 9, allowing residual process gas to be introduced into the buffer tank 21 for storage, so that it can be further processed or recovered when needed. In addition, the buffer tank, as a container for gas storage and buffering, can balance the system pressure and prevent gas pressure fluctuations from damaging the system. The compressor interface line 23 is connected to the primary recovery interface line 22 via the second remote switching valve 11, which is beneficial for the initial recovery and reuse of residual process gas.

[0027] The buffer tank 21 is connected to the flare interface line 24 via the second emergency vent valve 6. When the gas pressure in the buffer tank 21 is too high, the second emergency vent valve 6 is quickly opened, and the gas is safely discharged into the flare system for combustion through the flare interface line 24. The buffer tank 21 is connected to the secondary recovery interface line 25 via the third remote switching valve 14, which discharges the residual process gas into the compressor inlet network of the secondary recovery system for further processing and recovery of the residual process gas.

[0028] A pipeline pressure transmitter 27 is installed on the compressor interface pipeline 23, and the pipeline pressure transmitter 27 is electrically connected to the first emergency vent valve 4. A buffer tank pressure transmitter 28 is installed on the buffer tank 21, and the buffer tank pressure transmitter 28 is electrically connected to the third remote switching valve 14. The pipeline pressure transmitter 27 and the buffer tank pressure transmitter 28 are used to monitor the pressure in the compressor interface pipeline 23 and the buffer tank 21 in real time, so as to facilitate the control system to adjust the opening and closing status of each valve in real time and ensure the safe and stable operation of the system.

[0029] The first emergency vent valve 4, the second emergency vent valve 6, the first remote switching valve 9, the second remote switching valve 11, the third remote switching valve 14, the pipeline pressure transmitter 27, and the buffer tank pressure transmitter 28 are all connected to the control system. Through the control system, operators can remotely monitor and control the operating status of the entire system, achieving automated and intelligent management.

[0030] In summary, this invention enables real-time detection and accurate control of the venting and emission of residual process gas, achieving effective recovery and utilization of residual process gas.

[0031] Example 1: See Figure 1 This embodiment discloses a compressor vent air recovery system, including a compressor interface pipeline 23; The compressor interface line 23 is connected to the flare interface line 24 through the first emergency vent valve 4, the compressor interface line 23 is connected to the buffer tank 21 through the first remote switch valve 9, and the compressor interface line 23 is connected to the primary recovery interface line 22 through the second remote switch valve 11. The buffer tank 21 is connected to the flare interface pipeline 24 via the second emergency vent valve 6, and the buffer tank 21 is connected to the secondary recovery interface pipeline 25 via the third remote switch valve 14. The compressor interface pipeline 23 is equipped with a pipeline pressure transmitter 27, which is electrically connected to the first emergency vent valve 4. The buffer tank 21 is equipped with a buffer tank pressure transmitter 28, which is electrically connected to the third remote switching valve 14. The first emergency vent valve 4, the second emergency vent valve 6, the first remote switching valve 9, the second remote switching valve 11, the third remote switching valve 14, the pipeline pressure transmitter 27, and the buffer tank pressure transmitter 28 are all connected to the control system.

[0032] Preferably, the control system includes a SIS safety instrumented system 2 and a DCS distributed control system 3; The SIS safety instrumented system 2 is connected to the first emergency vent valve 4, the second emergency vent valve 6, the pipeline pressure transmitter 27, and the buffer tank pressure transmitter 28, respectively. The DCS distributed control system 3 is connected to the first remote switching valve 9, the second remote switching valve 11, the third remote switching valve 14, the pipeline pressure transmitter 27, and the buffer tank pressure transmitter 28, respectively.

[0033] Preferably, the pipeline pressure transmitter 27 includes a first pressure transmitter 5, which is located between the compressor interface pipeline 23 and the first emergency vent valve 4, and is electrically connected to the first emergency vent valve 4. The buffer tank pressure transmitter 28 includes a second pressure transmitter 7, which is electrically connected to a second emergency vent valve 6. The first pressure transmitter 5 and the second pressure transmitter 7 are both connected to the SIS safety instrumented system 2.

[0034] Preferably, the pipeline pressure transmitter 27 includes a third pressure transmitter 8, which is located between the compressor interface pipeline 23 and the second remote switching valve 11, and is electrically connected to the first remote switching valve 9. The buffer tank pressure transmitter 28 includes a fourth pressure transmitter 13, which is connected to a third remote switching valve 14. The third pressure transmitter 8 and the fourth pressure transmitter 13 are both connected to the DCS distributed control system 3.

[0035] Preferably, the secondary recovery interface line 25 is equipped with a first regulating valve 17 and a fifth pressure transmitter 18. The first regulating valve 17 is located between the third remote switching valve 14 and the fifth pressure transmitter 18. The first regulating valve 17 and the fifth pressure transmitter 18 are electrically connected to the control system. The first regulating valve 17 is used to adjust the flow rate of the secondary recovery interface line 25, and the fifth pressure transmitter 18 is used to detect the pressure of the compressor inlet pipeline in the secondary recovery system. When the compressor inlet pipeline pressure in the secondary recovery system is greater than a threshold, the third remote switching valve 14 is closed to ensure the safety of the system's gas path.

[0036] Preferably, the buffer tank 21 is connected to the three-stage recovery interface pipeline 26 via the fourth remote switching valve 15. The fourth remote switching valve 15 is electrically connected to the control system and the buffer tank pressure transmitter 28 respectively. By adding a recovery interface pipeline, the purpose of graded recovery of residual process gas according to pressure can be achieved.

[0037] Preferably, the three-stage recovery interface pipeline 26 is provided with a second regulating valve 19 and a sixth pressure transmitter 20. The second regulating valve 19 is located between the fourth remote switching valve 15 and the sixth pressure transmitter 20. The second regulating valve 19 and the sixth pressure transmitter 20 are electrically connected to the control system.

[0038] The specific usage method of the secondary recycling interface line 25 and the tertiary recycling interface line 26 in conjunction is as follows: When the pressure in the buffer tank 21 is greater than or equal to the seventh threshold pressure and less than the sixth threshold pressure, the control system closes the fourth remote switch valve 15 and opens the third remote switch valve 14. The residual process gas of the compressor 1 is discharged to the compressor inlet pipeline of the secondary recovery system through the third remote switch valve 14 and the secondary recovery interface pipeline 25. When the fourth pressure transmitter 13 detects that the pressure in the buffer tank 21 is less than the seventh threshold pressure and the fifth pressure transmitter 18 detects that the pressure in the compressor inlet pipeline of the secondary recovery system is greater than the eighth threshold pressure, the third remote switching valve 14 is closed. When the pressure in the buffer tank 21 is greater than or equal to the ninth threshold pressure and less than the seventh threshold pressure, the control system closes the third remote switch valve 14 and opens the fourth remote switch valve 15. The residual process gas of the compressor 1 is discharged to the inlet pipeline of the stabilizing gas compressor of the tertiary recovery system through the fourth remote switch valve 15 and the tertiary recovery interface pipeline 26. When the fourth pressure transmitter 13 detects that the pressure in the buffer tank 21 is less than the ninth threshold pressure and the sixth pressure transmitter 20 detects that the pressure in the inlet pipeline of the stabilizing gas compressor of the three-stage recovery system is greater than the tenth threshold pressure, the fourth remote switching valve 15 is activated.

[0039] Preferably, the buffer tank 21 is equipped with a level transmitter 16, which is electrically connected to the control system.

[0040] Preferably, a second check valve 12 is provided on the primary recycling interface pipeline 22.

[0041] Example 2: Please see Figure 1 As shown, this embodiment discloses a compressor venting recovery system, including a compressor 1, a SIS safety instrumented system 2, a DCS distributed control system 3, a first emergency venting valve 4, a first pressure transmitter 5, a second emergency venting valve 6, a second pressure transmitter 7, a third pressure transmitter 8, a first remote switching valve 9, a first check valve 10, a second remote switching valve 11, a second check valve 12, a fourth pressure transmitter 13, a third remote switching valve 14, a fourth remote switching valve 15, a level transmitter 16, a first regulating valve 17, a fifth pressure transmitter 18, a second regulating valve 19, a sixth pressure transmitter 20, a buffer tank 21, and process pipelines.

[0042] Compressor 1 is used to pressurize the process gas on site. The outlet vent line of compressor 1 is connected to the vent gas recovery system of the present invention for vent gas recovery. At the same time, compressor 1 is controlled by the on-site PLC programmable logic controller.

[0043] The SIS Safety Instrumented System 2 receives signals from the first emergency vent valve 4, the first pressure transmitter 5, the second emergency vent valve 6, and the second pressure transmitter 7. Through logic configuration, it interlocks the first emergency vent valve 4 with the first pressure transmitter 5, and the second emergency vent valve 6 with the second pressure transmitter 7. It controls the opening and closing of the first emergency vent valve 4 and the second emergency vent valve 6, ensuring that the first emergency vent valve 4 opens when the first pressure transmitter 5 detects overpressure in the pipeline, and the second emergency vent valve 6 opens when the second pressure transmitter 7 detects overpressure in the buffer tank. Simultaneously, the SIS Safety Instrumented System 2 should meet the SIL2 level requirements.

[0044] The DCS distributed control system 3 receives signals from the third pressure transmitter 8, the first remote switching valve 9, the second remote switching valve 11, the fourth pressure transmitter 13, the third remote switching valve 14, the fourth remote switching valve 15, the level transmitter 16, the first regulating valve 17, the fifth pressure transmitter 18, the second regulating valve 19, and the sixth pressure transmitter 20. Through logic configuration, it achieves interlocking between the first remote switching valve 9 and the third pressure transmitter 8, the second remote switching valve 11 and the third pressure transmitter 8, the third remote switching valve 14 and the fourth pressure transmitter 13, the fourth remote switching valve 15 and the fourth pressure transmitter 13, the first regulating valve 17 and the fifth pressure transmitter 18, and the second regulating valve 19 and the sixth pressure transmitter 20. Simultaneously, a host computer for the DCS distributed control system 3 is set up in the main control room to monitor the parameters of the entire system.

[0045] The first emergency vent valve 4 is connected to and controlled by the SIS safety instrumented system 2. It uses compressed air of 0.6~1.0MPa as a power source for emergency venting when the pipeline is overpressured. At the same time, the first emergency vent valve 4 should meet the SIL2 level requirements.

[0046] The first pressure transmitter 5 is used to detect the pressure of the compressed outlet vent line. The signal is connected to the SIS safety instrumented system 2. When the pressure value of the first pressure transmitter 5 is greater than or equal to 39 MPa, an alarm is triggered. When the pressure value is greater than or equal to the set value of 40 MPa, the first emergency vent valve 4 is interlocked and opened. After manual confirmation that the emergency venting is completed, the first emergency vent valve 4 is manually closed. In the event of a fire or leakage accident, after manual confirmation, the first emergency vent valve 4 is manually opened, while ensuring that the first remote switch valve 9 and the second remote switch valve 11 are in the closed state. After the accident is resolved, the first emergency vent valve 4 is manually closed. The first pressure transmitter 5 should also meet the SIL2 level requirements.

[0047] The second emergency vent valve 6 is connected to and controlled by the SIS safety instrument system 2. It uses compressed air of 0.6~1.0MPa as a power source for emergency venting when the buffer tank is overpressured. At the same time, the second emergency vent valve 6 should meet the SIL2 level requirements.

[0048] The second pressure transmitter 7 is used to detect the pressure of the buffer tank 21. The signal is connected to the SIS safety instrumented system 2. When the second pressure transmitter 7 detects a pressure value higher than 7.5 MPa, it alarms. When it exceeds the high limit setting of 8.0 MPa, it interlocks and opens the second emergency vent valve 6 to release air to the high-pressure flare system. When the pressure of the buffer tank 21 is lower than 7.5 MPa, the second emergency vent valve 6 closes. In the event of a fire or leak at the station, after manual confirmation, the second emergency vent valve 6 is manually opened to release air to the high-pressure flare system. At the same time, it is confirmed that the first remote switch valve 9, the third remote switch valve 14, and the fourth remote switch valve 15 are in the closed state. After the accident is resolved, the second emergency vent valve 6 is manually closed. The second pressure transmitter 7 should also meet the SIL2 level requirements.

[0049] The third pressure transmitter 8 is used to detect the pressure of the compressor venting pipeline. The signal is connected to the DCS distributed control system 3. When the pressure value detected by the third pressure transmitter 8 is greater than or equal to 8.0 MPa, the second remote switching valve 11 is interlocked open, and the vented air goes to the external pipeline of the primary recovery system. When the pressure value detected by the third pressure transmitter 8 is less than or equal to 7.0 MPa, the second remote switching valve 11 is interlocked closed. When the pressure detected by the third pressure transmitter 8 is greater than 0.1 MPa and less than or equal to 7.5 MPa, and the second remote switching valve 11 is in the open state, the first remote switching valve 9 is interlocked open, and the vented air goes to the buffer tank 21. When the pressure value detected by the third pressure transmitter 8 is less than or equal to 0.1 MPa, the first remote switching valve 9 is interlocked closed. At the same time, the first remote switching valve 9 and the second remote switching valve 11 have manual control functions. The manual control priority can be selected according to the venting time and the recovery requirements of the venting amount, and the opening and closing of the first remote switching valve 9 and the second remote switching valve 11 can be manually controlled.

[0050] The first remote switching valve 9 receives a signal from the DCS distributed control system 3 and is controlled by it. It uses compressed air of 0.6~1.0MPa as a power source and is interlocked with the third pressure transmitter 8 to release air to the buffer tank 21.

[0051] The first check valve 10 is used to prevent process gas from returning from the buffer tank 21 to the compressor vent line.

[0052] The second remote switching valve 11 is connected to and controlled by the DCS distributed control system 3. It uses compressed air of 0.6~1.0MPa as a power source and is interlocked with the third pressure transmitter 8 to control the release of air to the external pipeline of the primary recovery system.

[0053] The second check valve 12 is used to prevent process gas from returning from the primary recovery system's external pipeline to the compressor's vent line.

[0054] The fourth pressure transmitter 13 is used to detect the pressure of the buffer tank 21. The signal is connected to the DCS distributed control system 3. When the fourth pressure transmitter 13 detects a pressure value greater than or equal to the set value of 1.9 MPa, it interlocks and opens the third remote switch valve 14 to release air to the inlet pipeline of the compressor in the secondary recovery system. When the fourth pressure transmitter 13 detects a pressure value less than the set value of 1.9 MPa, or when the fifth pressure transmitter 18 detects a pressure value greater than the set value of 1.85 MPa, it interlocks and closes the third remote switch valve 14. When the fourth pressure transmitter 13 detects a pressure value greater than 0.1 MPa and less than 1.9 MPa, it interlocks and opens the fourth remote switch valve 15 to release air to the inlet pipeline of the stabilizing gas compressor in the tertiary recovery system. When the fourth pressure transmitter 13 detects a pressure value less than or equal to the set value of 0.1 MPa, or when the sixth pressure transmitter 20 detects a pressure value greater than the set value of 0.065 MPa, it interlocks and closes the fourth remote switch valve 15.

[0055] The third remote switching valve 14 is connected to and controlled by the DCS distributed control system 3. It uses compressed air of 0.6~1.0MPa as a power source. The third remote switching valve 14 is interlocked with the fourth pressure transmitter 13 to control the vented air to the inlet pipeline of the compressor in the secondary recovery system.

[0056] The signal of the fourth remote switching valve 15 is connected to and controlled by the DCS distributed control system 3. It uses compressed air of 0.6~1.0MPa as a power source. The fourth remote switching valve 15 is interlocked with the fourth pressure transmitter 13 to control the release air to the inlet pipeline of the stabilizing gas compressor of the three-stage recovery system.

[0057] The level transmitter 16 signal is connected to the DCS distributed control system 3 to detect the level of the buffer tank 21 and set a high level alarm.

[0058] The first regulating valve 17 is connected to and controlled by the DCS distributed control system 3. It uses compressed air of 0.6~1.0MPa as a power source. The first regulating valve 17 is interlocked with the fifth pressure transmitter 18 to control the pressure of the inlet pipeline of the compressed air compressor in the secondary recovery system to 1.85MPa.

[0059] The second regulating valve 19 is connected to and controlled by the DCS distributed control system 3. It uses compressed air of 0.6~1.0MPa as a power source. The second regulating valve 19 is interlocked with the sixth pressure transmitter 20 to control the pressure of the vented air to the inlet pipeline of the stabilizing gas compressor of the three-stage recovery system to 0.065MPa.

[0060] The buffer tank 21 has a volume of 50 cubic meters and is used for air buffering and storage.

[0061] Process pipelines are used for connections between valves and buffer tanks in the compressor vent air recovery system.

[0062] This invention, through the creation of a new process flow, control system, and automated instruments, automatically achieves stepped recovery of vented air while ensuring safety and reliability. It solves the problems of existing technologies that cannot control compressor vented air release, monitor compressor vented air pressure, or recover compressor vented air, thus avoiding resource waste and environmental pollution caused by compressor shutdown and venting. In the current context of green, low-carbon, and digital transformation, this invention proposes a new design concept for compressor venting systems, contributing to the advancement of the industry.

[0063] See Figure 3 This invention discloses a method for using a compressor vent air recovery system, comprising the following steps: S1, the pressure in the compressor interface pipeline 23 is obtained in real time through the pipeline pressure transmitter 27, and the pressure in the buffer tank 21 is obtained in real time through the buffer tank pressure transmitter 28; S2, when the pressure in the compressor interface line 23 is greater than or equal to the first threshold pressure of 40MPa, the control system closes the second emergency vent valve 6, the first remote switch valve 9 and the second remote switch valve 11, and opens the first emergency vent valve 4. The residual process gas of the compressor 1 is discharged to the flare for combustion treatment through the first emergency vent valve 4 and the flare interface line 24. S3, when the pressure in the compressor interface pipeline 23 is greater than or equal to the second threshold pressure of 39MPa and less than the first threshold pressure of 40MPa, the control system activates the pipeline pressure transmitter 27 to alarm. S4, when the pressure in the compressor interface line 23 is greater than or equal to the third threshold pressure of 8MPa and less than the second threshold pressure of 39MPa, the control system closes the first emergency vent valve 4 and the first remote switching valve 9, and opens the second remote switching valve 11. The residual process gas of the compressor 1 is discharged and recovered through the second remote switching valve 11 and the first-stage recovery interface line 22. S5, when the pressure in the compressor interface pipeline 23 is greater than or equal to the fourth threshold pressure of 0.1MPa and less than the third threshold pressure of 8MPa, the control system closes the first emergency vent valve 4, the second emergency vent valve 6 and the second remote switch valve 11, and opens the first remote switch valve 9, so that the residual process gas of the compressor 1 is discharged into the buffer tank 21 through the first remote switch valve 9. S6, when the pressure in the buffer tank 21 is greater than or equal to the fifth threshold pressure of 8MPa, the control system closes the first emergency vent valve 4, the first remote switch valve 9 and the third remote switch valve 14, and opens the second emergency vent valve 6. The residual process gas of the compressor 1 is discharged to the flare for combustion treatment through the second emergency vent valve 6 and the flare interface pipeline 24. S7, when the pressure in the buffer tank 21 is greater than or equal to the sixth threshold pressure of 7.5MPa and less than the fifth threshold pressure of 8MPa, the buffer tank pressure transmitter 28 is activated to trigger an alarm. S8, when the pressure in the buffer tank 21 is greater than or equal to the seventh threshold pressure of 1.9 MPa and less than the sixth threshold pressure of 7.5 MPa, the control system closes the second emergency vent valve 6 and opens the third remote switching valve 14. The residual process gas of the compressor 1 is discharged and recovered through the third remote switching valve 14 and the secondary recovery interface pipeline 25.

[0064] In summary, this invention enables real-time detection and accurate control of the venting and emission of residual process gas, achieving effective recovery and utilization of residual process gas.

[0065] Example 3: See Figure 2 Based on the above embodiments, this embodiment discloses a method for using a compressor vent air recovery system, including the following steps: In this embodiment, the first threshold pressure is 40 MPa, the second threshold pressure is 39 MPa, the third threshold pressure is 8 MPa, the fourth threshold pressure is 0.1 MPa, the fifth threshold pressure is 8 MPa, the sixth threshold pressure is 7.5 MPa, the seventh threshold pressure is 1.9 MPa, the eighth threshold pressure is 1.85 MPa, the ninth threshold pressure is 0.1 MPa, and the tenth threshold pressure is 0.065 MPa. S1, the pressure in the compressor interface pipeline 23 is obtained in real time through the pipeline pressure transmitter 27, and the pressure in the buffer tank 21 is obtained in real time through the buffer tank pressure transmitter 28; S2, when the pressure in the compressor interface line 23 is greater than or equal to 40MPa, the control system closes the second emergency vent valve 6, the first remote switch valve 9 and the second remote switch valve 11, and opens the first emergency vent valve 4. The residual process gas of the compressor 1 is discharged to the flare for combustion treatment through the first emergency vent valve 4 and the flare interface line 24. S3, when the pressure in the compressor interface pipeline 23 is greater than or equal to 39MPa and less than 40MPa, the control system activates the pipeline pressure transmitter 27 to alarm. S4, when the pressure in the compressor interface line 23 is greater than or equal to 8MPa and less than 39MPa, the control system closes the first emergency vent valve 4 and the first remote switch valve 9, and opens the second remote switch valve 11. The residual process gas of the compressor 1 is discharged and recovered through the second remote switch valve 11 and the first-stage recovery interface line 22. S5, when the pressure in the compressor interface pipeline 23 is greater than or equal to 0.1MPa and less than 8MPa, the control system closes the first emergency vent valve 4, the second emergency vent valve 6 and the second remote switch valve 11, and opens the first remote switch valve 9, so that the residual process gas of the compressor 1 is discharged into the buffer tank 21 through the first remote switch valve 9. S6, when the pressure in the buffer tank 21 is greater than or equal to 8MPa, the control system closes the first emergency vent valve 4, the first remote switch valve 9 and the third remote switch valve 14, and opens the second emergency vent valve 6. The residual process gas of the compressor 1 is discharged to the flare for combustion treatment through the second emergency vent valve 6 and the flare interface pipeline 24. S7, when the pressure in the buffer tank 21 is greater than or equal to 7.5MPa and less than 8MPa, control the start of the buffer tank pressure transmitter 28 to trigger an alarm; S8, when the pressure in the buffer tank 21 is greater than or equal to 1.9MPa and less than 7.5MPa, the control system closes the second emergency vent valve 6 and opens the third remote switching valve 14. The residual process gas of the compressor 1 is discharged and recovered through the third remote switching valve 14 and the secondary recovery interface pipeline 25.

[0066] S9, when the pressure in the buffer tank 21 is greater than or equal to 1.9MPa and less than 7.5MPa, the control system closes the fourth remote switch valve 15 and opens the third remote switch valve 14. The residual process gas of the compressor 1 is discharged to the compressor inlet pipeline of the secondary recovery system through the third remote switch valve 14 and the secondary recovery interface pipeline 25. S10, when the fourth pressure transmitter 13 detects that the pressure in the buffer tank 21 is less than 1.9MPa and the fifth pressure transmitter 18 detects that the pressure in the compressor inlet pipeline of the secondary recovery system is greater than 1.85MPa, the third remote switch valve 14 is closed. S11, when the pressure in the buffer tank 21 is greater than or equal to 0.1MPa and less than 1.9MPa, the control system closes the third remote switch valve 14 and opens the fourth remote switch valve 15. The residual process gas of the compressor 1 is discharged to the inlet pipeline of the pressure stabilizing gas compressor of the three-stage recovery system through the fourth remote switch valve 15 and the three-stage recovery interface pipeline 26. S12, when the fourth pressure transmitter 13 detects that the pressure in the buffer tank 21 is less than 0.1MPa and the sixth pressure transmitter 20 detects that the pressure in the inlet pipeline of the three-stage recovery system pressure stabilizing gas compressor is greater than 0.065MPa, the fourth remote switching valve 15.

[0067] Example 4: See Figure 2 This embodiment provides a method for using a compressor vent air recovery system, as detailed below: S1, the compressor vent air recovery adopts a stepped system pipeline recovery method, with three levels of recovery. When the detection pressure of the third pressure transmitter 8 on the compressor outlet vent pipeline is greater than or equal to 8.0 MPa, the second remote switch valve 11 is interlocked and opened, and the vent air goes to the external pipeline of the first-level recovery system. When the detection pressure of the third pressure transmitter 8 is less than or equal to 7.0 MPa, the second remote switch valve 11 is interlocked and closed. When the detection pressure of the third pressure transmitter 8 is greater than 0.1 MPa and less than or equal to 7.5 MPa, and the second remote switch valve 11 is in the open state, the first remote switch valve 9 is interlocked and opened, and the vent air goes to the buffer tank 21. When the detection pressure of the third pressure transmitter 8 is less than or equal to 0.1 MPa, the first remote switch valve 9 is interlocked and closed.

[0068] S2, when the detected pressure of the fourth pressure transmitter 13 at the top of the buffer tank is greater than or equal to 1.9 MPa, the third remote switch valve 14 is interlocked open to release air to the inlet pipeline of the compressor in the secondary recovery system; when the detected pressure of the fourth pressure transmitter 13 is less than 1.9 MPa or the pressure of the fifth pressure transmitter 18 is greater than 1.85 MPa, the third remote switch valve 14 is interlocked closed. When the detected pressure of the fourth pressure transmitter 13 is greater than 0.1 MPa and less than 1.9 MPa, the fourth remote switch valve 15 is interlocked open to release air to the inlet pipeline of the stabilizing gas compressor in the tertiary recovery system; when the pressure of the fourth pressure transmitter 13 is less than or equal to 0.1 MPa or the pressure of the sixth pressure transmitter 20 is greater than 0.065 MPa, the fourth remote switch valve 15 is interlocked closed.

[0069] S3, when the detected pressure of the first pressure transmitter 5 is greater than or equal to 39MPa, an alarm is triggered. When the detected pressure of the first pressure transmitter 5 is greater than or equal to 40MPa, the first emergency vent valve 4 is interlocked and opened. After the emergency venting is confirmed by manual confirmation, the first emergency vent valve 4 is manually closed.

[0070] S4, when the second pressure transmitter 7 detects a pressure value greater than or equal to 7.5MPa, an alarm is triggered. When the pressure value is greater than or equal to the high limit setting value of 8.0MPa, the second emergency vent valve 6 is interlocked to release air to the high-pressure flare venting system.

[0071] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A compressor air recovery system, characterized in that, Including compressor interface pipeline (23); The compressor interface line (23) is connected to the torch interface line (24) through the first emergency vent valve (4), the compressor interface line (23) is connected to the buffer tank (21) through the first remote switch valve (9), and the compressor interface line (23) is connected to the primary recovery interface line (22) through the second remote switch valve (11). The buffer tank (21) is connected to the torch interface line (24) via the second emergency vent valve (6), and the buffer tank (21) is connected to the secondary recovery interface line (25) via the third remote switch valve (14). The compressor interface pipeline (23) is equipped with a pipeline pressure transmitter (27), which is electrically connected to the first emergency vent valve (4). The buffer tank (21) is equipped with a buffer tank pressure transmitter (28), which is electrically connected to the third remote switching valve (14). The first emergency vent valve (4), the second emergency vent valve (6), the first remote switching valve (9), the second remote switching valve (11), the third remote switching valve (14), the pipeline pressure transmitter (27), and the buffer tank pressure transmitter (28) are all connected to the control system.

2. The compressor exhaust air recovery system according to claim 1, characterized in that, The control system includes a SIS safety instrumented system (2) and a DCS distributed control system (3). The SIS safety instrumented system (2) is connected to the first emergency vent valve (4), the second emergency vent valve (6), the pipeline pressure transmitter (27), and the buffer tank pressure transmitter (28), respectively. The DCS distributed control system (3) is connected to the first remote switching valve (9), the second remote switching valve (11), the third remote switching valve (14), the pipeline pressure transmitter (27), and the buffer tank pressure transmitter (28), respectively.

3. The compressor exhaust air recovery system according to claim 2, characterized in that, The pipeline pressure transmitter (27) includes a first pressure transmitter (5), which is located between the compressor interface pipeline (23) and the first emergency vent valve (4). The first pressure transmitter (5) is electrically connected to the first emergency vent valve (4). The buffer tank pressure transmitter (28) includes a second pressure transmitter (7), which is electrically connected to a second emergency vent valve (6). The first pressure transmitter (5) and the second pressure transmitter (7) are both connected to the SIS safety instrumented system (2).

4. The compressor exhaust air recovery system according to claim 2, characterized in that, The pipeline pressure transmitter (27) includes a third pressure transmitter (8), which is located between the compressor interface pipeline (23) and the second remote switching valve (11). The third pressure transmitter (8) is electrically connected to the first remote switching valve (9). The buffer tank pressure transmitter (28) includes a fourth pressure transmitter (13), which is connected to a third remote switching valve (14). The third pressure transmitter (8) and the fourth pressure transmitter (13) are both connected to the DCS distributed control system (3).

5. The compressor exhaust air recovery system according to claim 1, characterized in that, The secondary recovery interface pipeline (25) is equipped with a first regulating valve (17) and a fifth pressure transmitter (18). The first regulating valve (17) is located between the third remote switching valve (14) and the fifth pressure transmitter (18). The first regulating valve (17) and the fifth pressure transmitter (18) are electrically connected to the control system.

6. The compressor exhaust air recovery system according to claim 1, characterized in that, The buffer tank (21) is connected to the three-stage recovery interface pipeline (26) through the fourth remote switching valve (15). The fourth remote switching valve (15) is electrically connected to the control system and the buffer tank pressure transmitter (28).

7. The compressor exhaust air recovery system according to claim 6, characterized in that, The three-stage recovery interface pipeline (26) is equipped with a second regulating valve (19) and a sixth pressure transmitter (20). The second regulating valve (19) is located between the fourth remote switching valve (15) and the sixth pressure transmitter (20). The second regulating valve (19) and the sixth pressure transmitter (20) are electrically connected to the control system.

8. The compressor exhaust air recovery system according to claim 1, characterized in that, The buffer tank (21) is equipped with a level transmitter (16), which is electrically connected to the control system.

9. The compressor exhaust air recovery system according to claim 1, characterized in that, A second check valve (12) is provided on the primary recycling interface pipeline (22).

10. A method of using a compressor vent air recovery system, characterized in that, Includes the following steps: The pressure in the compressor interface pipeline (23) is obtained in real time through the pipeline pressure transmitter (27), and the pressure in the buffer tank (21) is obtained in real time through the buffer tank pressure transmitter (28). When the pressure in the compressor interface line (23) is greater than or equal to the first threshold pressure, the control system closes the second emergency vent valve (6), the first remote switch valve (9) and the second remote switch valve (11), and opens the first emergency vent valve (4). The residual process gas of the compressor (1) is discharged to the flare for combustion treatment through the first emergency vent valve (4) and the flare interface line (24). When the pressure in the compressor interface pipeline (23) is greater than or equal to the second threshold pressure and less than the first threshold pressure, the control system activates the pipeline pressure transmitter (27) to alarm. When the pressure in the compressor interface line (23) is greater than or equal to the third threshold pressure and less than the second threshold pressure, the control system closes the first emergency vent valve (4) and the first remote switch valve (9), and opens the second remote switch valve (11). The residual process gas of the compressor (1) is discharged and recovered through the second remote switch valve (11) and the first-level recovery interface line (22). When the pressure in the compressor interface pipeline (23) is greater than or equal to the fourth threshold pressure and less than the third threshold pressure, the control system closes the first emergency vent valve (4), the second emergency vent valve (6) and the second remote switch valve (11), and opens the first remote switch valve (9). The residual process gas of the compressor (1) is discharged into the buffer tank (21) through the first remote switch valve (9). When the pressure in the buffer tank (21) is greater than or equal to the fifth threshold pressure, the control system closes the first emergency vent valve (4), the first remote switch valve (9) and the third remote switch valve (14), and opens the second emergency vent valve (6). The residual process gas of the compressor (1) is discharged to the flare for combustion treatment through the second emergency vent valve (6) and the flare interface pipeline (24). When the pressure in the buffer tank (21) is greater than or equal to the sixth threshold pressure and less than the fifth threshold pressure, the buffer tank pressure transmitter (28) is activated to trigger an alarm. When the pressure in the buffer tank (21) is greater than or equal to the seventh threshold pressure and less than the sixth threshold pressure, the control system closes the second emergency vent valve (6) and opens the third remote switch valve (14). The residual process gas of the compressor (1) is discharged and recovered through the third remote switch valve (14) and the secondary recovery interface pipeline (25).

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