Multifunctional self-adaptive treatment system and process for ground centralized mining of shale gas

Abstract

The invention relates to a multifunctional self-adaptive treatment system and process for ground centralized mining of shale gas, and belongs to the technical field of oil and gas field mining treatment. The multifunctional self-adaptive treatment system for ground centralized mining of shale gas comprises a desanding separator, a first pressure measuring piece, a first liquid level meter and a controller; the desanding separator is provided with a raw material gas inlet pipe, a first liquid phase outlet pipe and a wet gas outlet pipe, a pressure regulating valve is mounted on the raw material gas inlet pipe, a first sand discharging valve is mounted on the first liquid phase outlet pipe, and the desanding separator is used for removing sand grains and free liquid so as to output wet gas from the wet gas outlet pipe; the controller adjusts the opening degree of the pressure adjusting valve according to the pressure value detected by the first pressure measuring piece, and the controller adjusts the opening degree of the first sand discharging valve according to the liquid level height value detected by the first liquid level meter. The system has the effects that it is guaranteed that the system adapts to different working condition environments of all stages of shale gas exploitation, and the desanding efficiency and normal operation of the system are guaranteed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil and gas field exploitation and processing, and in particular to a shale gas surface centralized exploitation multifunctional adaptive processing system and process. BACKGROUND

[0002] The pretreatment process of shale gas surface exploitation is a key link before shale gas centralized transportation. The pretreatment process mainly uses an integrated container integrating the functions of sand removal, separation, metering and defoaming to ensure that the gas discharged from the pipeline system meets the operation requirements of the downstream centralized transportation facilities and guarantees the normal and safe production process.

[0003] At present, the pretreatment process equipment mainly relies on manual operation, and the site personnel perform sand discharge, adjustment of raw gas inlet flow and other operations according to experience. However, in the initial production stage of the well opening, the raw gas often has the characteristics of high sand content and high liquid content, and the proportions of gas, liquid and sand in the raw gas change dramatically. If the operator lacks experience or the operation response is not timely, it is easy to cause the mismatch between the process parameters and the real-time working conditions, resulting in reduced sand removal efficiency or even non-gas components entering the gas pipeline, which affects the normal operation of the process. SUMMARY

[0004] In order to help ensure that the system adapts to different working conditions in each stage of shale gas exploitation and guarantee the sand removal efficiency and normal operation of the system, the present application provides a shale gas surface centralized exploitation multifunctional adaptive processing system and process.

[0005] In the first aspect, the present application provides a shale gas surface centralized exploitation multifunctional adaptive processing system, which adopts the following technical solution: A shale gas surface centralized exploitation multifunctional adaptive processing system, comprising: A sand removal separator, the sand removal separator has a raw gas inlet pipe, a first liquid phase outlet pipe and a wet gas outlet pipe, the raw gas inlet pipe is used to communicate with the wellhead to input raw gas, a pressure regulating valve is installed on the raw gas inlet pipe, the first liquid phase outlet pipe is used to communicate with an external blowdown pipe, a first sand discharge valve is installed on the first liquid phase outlet pipe, and the sand removal separator is used to remove sand particles and free liquid to output wet gas from the wet gas outlet pipe; A first pressure measuring element, the first pressure measuring element is used to measure the internal pressure of the sand removal separator; A first liquid level meter, the first liquid level meter is used to measure the liquid level height inside the sand removal separator; A controller, the sand removal separator, the pressure regulating valve, the first sand discharge valve, the first pressure measuring element and the first liquid level meter are all electrically connected with the controller, the controller adjusts the opening degree of the pressure regulating valve according to the pressure value detected by the first pressure measuring element, and the controller adjusts the opening degree of the first sand discharge valve according to the liquid level height value detected by the first liquid level meter.

[0006] Preferably, the treatment system further includes a gravity separator, a second level gauge, and a second pressure measuring device. The gravity separator has a wet gas inlet pipe, a second liquid phase outlet pipe, and a dry gas outlet pipe. The wet gas inlet pipe is connected to the wet gas outlet pipe. The second liquid phase outlet pipe is used to connect to an external sewage pipe. A second sand discharge valve is installed on the second liquid phase outlet pipe. The dry gas outlet pipe is used to connect to an external collection and transportation pipeline. The gravity separator is used to perform gas-liquid separation to output treated gas from the dry gas outlet pipe. The second level gauge is used to measure the liquid level height inside the gravity separator. The second pressure measuring device is used to measure the internal pressure of the gravity separator. The gravity separator, the second level gauge, and the second sand discharge valve are all electrically connected to a controller. The controller adjusts the opening degree of the second sand discharge valve according to the liquid level height value detected by the second level gauge.

[0007] Preferably, multiple sand separators are provided, and the moisture outlet pipes of the multiple sand separators are all connected to the moisture inlet pipe. A first flow meter and a check valve are installed on the moisture outlet pipes of the multiple sand separators, and the check valve is located downstream of the corresponding first flow meter.

[0008] Preferably, the raw material gas inlet pipes of the plurality of sand separators are connected by a connecting pipe, which is located downstream of the pressure regulating valve.

[0009] Preferably, the processing system also includes a skid, on which the sand separator, gravity separator and controller are all integrated.

[0010] Preferably, the treatment system further includes a buffer tank, which has a liquid phase inlet pipe and a third liquid phase outlet pipe. The second liquid phase outlet pipe is connected to the liquid phase inlet pipe, and the third liquid phase outlet pipe is used to connect to an external sewage pipe. A first regulating valve is installed on the third liquid phase outlet pipe. A backflushing pipe is connected to the bottom of the sand separator. The backflushing pipe is connected to the buffer tank through a backflushing pump. A second regulating valve is installed on the backflushing pipe. The backflushing pump, the first regulating valve, and the second regulating valve are all electrically connected to a controller. A branch pipe is connected between the backflushing pipe and the first liquid phase outlet pipe. The branch pipe is located upstream of the first sand discharge valve.

[0011] Secondly, this application provides a multi-functional adaptive processing technology for centralized surface extraction of shale gas, which adopts the following technical solution: A multi-functional adaptive processing technology for centralized surface extraction of shale gas, using the aforementioned processing system, further includes the following steps: When the system starts working, the controller drives the pressure regulating valve to open and the first and second sand discharge valves to close. The wellhead raw gas enters the desand separator through the raw gas inlet pipe. The first pressure measuring device measures the pressure inside the desand separator, and the controller adjusts the opening of the pressure regulating valve according to the pressure value detected by the first pressure measuring device. After the raw material gas in the sand separator is processed, the moisture is discharged through the moisture outlet pipe to the moisture inlet pipe. The first level gauge detects the liquid level inside the sand separator. When the first level gauge detects that the liquid level inside the sand separator has reached the first preset value, the controller drives the first sand discharge valve to open, and the sand-containing liquid phase inside the sand separator is discharged to the external sewage pipe through the first liquid phase outlet pipe. The controller adjusts the opening of the first sand discharge valve based on the liquid level height detected by the first liquid level gauge; Moisture entering the gravity separator from the moisture inlet pipe is separated and treated, and the treated gas is discharged from the dry gas outlet pipe. The second level gauge detects the liquid level inside the gravity separator. When the second level gauge detects that the liquid level inside the gravity separator has reached the second preset value, the controller drives the second sand discharge valve to open, and the liquid phase inside the gravity separator is discharged from the second liquid phase outlet pipe to the external drain pipe. The controller adjusts the opening of the second sand discharge valve based on the liquid level height detected by the second liquid level gauge.

[0012] Preferably, the controller adjusts the opening of the pressure regulating valve according to the pressure value detected by the first pressure measuring device, including setting the preset pressure value P in the sand separator and the stabilization range P1-P2, where P = (P1+P2) / 2; after the first pressure measuring device detects that the pressure value reaches the preset pressure value P for the first time, the system reaches the first equilibrium state; when the system reaches the first equilibrium state, if the pressure value detected by the first pressure measuring device is within the stabilization range P1-P2, the controller drives the pressure regulating valve to maintain the current opening; when the system reaches the first equilibrium state, if the pressure value detected by the first pressure measuring device is less than the stabilization range P1-P2, the controller drives the opening of the pressure regulating valve to increase; when the system reaches the first equilibrium state... When the pressure value detected by the first pressure measuring device is greater than the pressure stabilization range P1-P2, the controller drives the pressure regulating valve to decrease its opening. The controller sets the pressure change gradient of the sand separator to P0, where P0 = P2-P1. After the system reaches the first equilibrium state, when the pressure value detected by the first pressure measuring device decreases by one P0, the controller drives the pressure regulating valve to increase its opening by 10%. When the pressure value detected by the first pressure measuring device decreases by five P0, the controller drives the pressure regulating valve to fully open. After the system reaches the first equilibrium state, when the pressure value detected by the first pressure measuring device increases by one P0, the controller drives the pressure regulating valve to decrease its opening by 10%. When the pressure value detected by the first pressure measuring device increases by five P0, the controller drives the pressure regulating valve to fully close.

[0013] Preferably, the controller adjusts the opening of the first sand discharge valve according to the liquid level height detected by the first level gauge. This includes setting the following parameters for the controller: 20% of the sand separator cylinder height as H0, 30% as H1, 50% as H2, 80% as H3, a safe liquid level range in the sand separator between H1 and H2, a low-level alarm threshold for the liquid level in the sand separator as H0, and a high-level alarm threshold for the liquid level in the sand separator as H3. Here, H1 is a first preset value. During system start-up and pressure increase or during pressure stabilization, when the first level gauge detects sand discharge... When the liquid level inside the separator reaches H1, the controller drives the first sand discharge valve to open; when the first level gauge detects that the liquid level inside the sand separator is within the safe range of H1-H2, the controller uses a PID fuzzy control algorithm to adjust the opening of the first sand discharge valve; when the first level gauge detects that the liquid level inside the sand separator is within H2-H3, the controller drives the opening of the first sand discharge valve to be adjusted to 50%; when the first level gauge detects that the liquid level inside the sand separator is higher than H3, the controller drives the first sand discharge valve to fully open; when the first level gauge detects that the liquid level inside the sand separator is lower than H0, the controller drives the first sand discharge valve to fully close.

[0014] Preferably, the controller adjusts the opening of the second sand discharge valve according to the liquid level height detected by the second level gauge. This includes setting the gravity separator cylinder height as 20% (h0), 30% (h1), 50% (h2), and 80% (h3), with a safe liquid level range of h1-h2 in the gravity separator, a low liquid level alarm threshold of h0, and a high liquid level alarm threshold of h3. Here, h1 is a first preset value. When the second level gauge detects that the liquid level in the gravity separator has risen to h1, the controller drives... The second sand discharge valve is open at an opening degree of 5%-10%; when the second level gauge detects that the liquid level in the gravity separator is within h1-h2, the controller drives the opening degree of the second sand discharge valve to adjust to 10%; when the second level gauge detects that the liquid level in the gravity separator is within h2-h3, the controller drives the opening degree of the second sand discharge valve to adjust to 20%; when the second level gauge detects that the liquid level in the gravity separator is greater than h3, the controller drives the opening degree of the second sand discharge valve to adjust to 50%-100%; when the second level gauge detects that the liquid level in the gravity separator is lower than h0, the controller drives the second sand discharge valve to close.

[0015] In summary, this application includes the following beneficial technical effects: When the system starts working, the controller drives the pressure regulating valve to open and the first sand discharge valve to close. The wellhead raw gas enters the desander through the raw gas inlet pipe. The first pressure measuring device measures the pressure inside the desander. The controller adjusts the opening of the pressure regulating valve according to the pressure value detected by the first pressure measuring device. Then, after the raw gas in the desander is processed, the gas phase is discharged through the wet gas outlet pipe. The first liquid level gauge detects the liquid level height inside the desander. When the liquid level height detected by the first liquid level gauge reaches the first preset value, the controller drives the first sand discharge valve to open. The sand-containing liquid phase in the desander is discharged to the external drain pipe through the first liquid phase outlet pipe. Then, the controller dynamically adjusts the opening of the first sand discharge valve according to the liquid level height detected by the first liquid level gauge. This application uses a controller to automatically adjust the opening of the pressure regulating valve and the first sand discharge valve, which helps to reduce labor intensity and ensure that the system adapts to different working conditions at various stages of shale gas extraction, thereby helping to ensure sand removal efficiency and normal system operation. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the processing system in Embodiment 1 of this application.

[0017] Figure 2 This is a schematic diagram of the overall structure of Embodiment 2 of this application.

[0018] Explanation of reference numerals in the attached diagram: 1. Sand separator; 2. Raw material gas inlet pipe; 3. First liquid phase outlet pipe; 4. Moist gas outlet pipe; 5. Pressure regulating valve; 6. First sand discharge valve; 7. First pressure measuring element; 8. First level gauge; 9. Gravity separator; 10. Second level gauge; 11. Second pressure measuring element; 12. Moist gas inlet pipe; 13. Second liquid phase outlet pipe; 14. Dry gas outlet pipe; 15. Second sand discharge valve; 16. First flow meter; 17. Check valve; 18. Connecting pipe; 19. Buffer tank; 20. Liquid phase inlet pipe; 21. Third liquid phase outlet pipe; 22. First regulating valve; 23. Backflush pipe; 24. Second regulating valve; 25. Branch pipe; 26. Backflush pump; 27. Third level gauge; 28. Second flow meter. Detailed Implementation

[0019] The following combination Figures 1-2 This application will be described in further detail.

[0020] Example 1:

[0021] This application discloses a multifunctional adaptive processing system for centralized surface extraction of shale gas. (Refer to...) Figure 1The multi-functional adaptive processing system for centralized shale gas surface extraction includes a desander separator 1, a first pressure measuring element 7, a first liquid level gauge 8, and a controller (not shown in the figure). The desander separator 1 has a raw gas inlet pipe 2, a first liquid phase outlet pipe 3, and a wet gas outlet pipe 4. The raw gas inlet pipe 2 is located on the side wall of the desander separator 1 cylinder and is used to connect to the wellhead to input raw gas. A pressure regulating valve 5 is installed on the raw gas inlet pipe 2. The first liquid phase outlet pipe 3 is located at the bottom of the desander separator 1 cylinder and is used to connect to an external sewage pipe. A first sand discharge valve 6 is installed on the first liquid phase outlet pipe 3. The wet gas outlet pipe 4 is located at the top of the desander separator 1 cylinder and is used by the desander separator 1 to remove sand particles and free liquid, so that wet gas is output from the wet gas outlet pipe 4. Specifically, the desander separator 1 can be selected as a device integrating desandering, defoaming, metering, and separation functions as needed. The internal structure and principle of the desander separator 1 are existing technologies and will not be elaborated here.

[0022] Reference Figure 1 The first pressure measuring element 7 is installed on the upper end of the tank of the sand separator 1, above the raw material gas inlet pipe 2, so that the first pressure measuring element 7 is installed in the upper gas phase space region of the sand separator 1. The first pressure measuring element 7 is used to measure the pressure inside the sand separator 1. Specifically, the first pressure measuring element 7 is a pressure transmitter. In other embodiments, the first pressure measuring element 7 can also be a pressure sensor, etc. The first level gauge 8 is installed on the tank of the sand separator 1 and below the raw material gas inlet pipe 2. The first level gauge 8 is used to measure the liquid level height inside the sand separator 1.

[0023] Reference Figure 1 The sand separator 1, pressure regulating valve 5, first sand discharge valve 6, first pressure measuring element 7 and first level gauge 8 are all electrically connected to the controller. The controller adjusts the opening of the pressure regulating valve 5 according to the pressure value detected by the first pressure measuring element 7, and adjusts the opening of the first sand discharge valve 6 according to the liquid level height value detected by the first level gauge 8.

[0024] When the system starts working, the controller drives the pressure regulating valve 5 to open and the first sand discharge valve 6 to close. The wellhead feed gas enters the desand separator 1 through the feed gas inlet pipe 2. The first pressure measuring element 7 measures the pressure inside the desand separator 1. The controller dynamically adjusts the opening of the pressure regulating valve 5 based on the pressure value detected by the first pressure measuring element 7. Then, after processing, the feed gas in the desand separator 1 is discharged through the wet gas outlet pipe 4. The first level gauge 8 detects the liquid level inside the desand separator 1. When the liquid level detected by the first level gauge 8 reaches a first preset value, the controller drives the first sand discharge valve 6 to open, removing the feed gas. The sand-containing liquid phase in the sand separator 1 is discharged to the external sewage pipe through the first liquid phase outlet pipe 3. Then, the controller dynamically adjusts the opening of the first sand discharge valve 6 according to the liquid level height detected by the first liquid level gauge 8. This application uses the controller to automatically adjust the opening of the pressure regulating valve 5 and the first sand discharge valve 6, and remotely interacts with process parameters such as flow rate and pressure, reducing labor intensity and helping to ensure that the system adapts to different working conditions at various stages of shale gas extraction. This makes it less likely for blockages or non-gas phases to enter the gas transmission pipeline, thereby helping to ensure sand removal efficiency and normal system operation, and improving the stability and reliability of the system.

[0025] Reference Figure 1 To further improve the separation effect, the treatment system also includes a gravity separator 9, a second liquid level gauge 10, and a second pressure measuring element 11. The gravity separator 9 has a moisture inlet pipe 12, a second liquid phase outlet pipe 13, and a dry gas outlet pipe 14. The moisture inlet pipe 12 is located on the side wall of the gravity separator 9 cylinder and is connected to the moisture outlet pipe 4, so as to facilitate the entry of the moisture treated in the sand separator 1 into the gravity separator 9. Specifically, the internal structure and principle of the gravity separator 9 are existing technologies and will not be described in detail here.

[0026] Reference Figure 1 The second liquid phase outlet pipe 13 is located at the bottom of the gravity separator 9 cylinder and is used to connect with the external sewage pipe. A second sand discharge valve 15 is installed on the second liquid phase outlet pipe 13. The dry gas outlet pipe 14 is located at the top of the gravity separator 9 cylinder and is used to connect with the external collection and transmission pipeline. A second flow meter 28 is installed on the dry gas outlet pipe 14. Specifically, the second flow meter 28 is a Venturi differential pressure flow meter to measure the gas flow rate discharged to the collection and transmission pipeline. The gravity separator 9 is used to perform gas-liquid separation so that processed gas is output from the dry gas outlet pipe 14.

[0027] Reference Figure 1The second pressure measuring element 11 is installed on the gravity separator 9, and is located above the moisture inlet pipe 12, so that the second pressure measuring element 11 is located in the gas phase space region of the gravity separator 9. The second pressure measuring element 11 is used to measure the pressure inside the gravity separator 9. Specifically, the second pressure measuring element 11 is a pressure transmitter. In other embodiments, the second pressure measuring element 11 can also be a pressure sensor, etc. The second level gauge 10 is installed on the tank of the gravity separator 9 and is located below the moisture inlet pipe 12. The second level gauge 10 is used to measure the liquid level height inside the gravity separator 9. The gravity separator 9, the second level gauge 10, the second pressure measuring element 11, the second flow meter 28, and the second sand discharge valve 15 are all electrically connected to the controller. The controller adjusts the opening degree of the second sand discharge valve 15 according to the liquid level height value detected by the second level gauge 10.

[0028] When the system first starts working, the second sand discharge valve 15 is closed. Moist gas entering the gravity separator 9 from the moisture inlet pipe 12 is separated and the treated gas is discharged from the dry gas outlet pipe 14 to the gathering and transportation pipeline. The liquid level inside the gravity separator 9 is detected by the second level gauge 10. When the liquid level detected by the second level gauge 10 reaches a second preset value, the controller drives the second sand discharge valve 15 to open, and the liquid phase inside the gravity separator 9 is discharged from the second liquid phase outlet pipe 13 to the external drain pipe. Then, the controller dynamically adjusts the opening of the second sand discharge valve 15 according to the liquid level detected by the second level gauge 10. Further separation of the moist gas discharged from the sand separator 1 by the gravity separator 9 helps ensure that the treated gas meets the subsequent gathering and transportation requirements. At the same time, the dynamic adjustment of the opening of the second sand discharge valve 15 by the controller not only reduces manual labor intensity but also adapts to different working conditions at different stages of mining, preventing non-gas phases from entering the gas transmission pipeline and ensuring the normal operation of the system.

[0029] Reference Figure 1 To simultaneously process multiple shale gas wells, multiple desanding separators 1 are installed. Specifically, each desanding separator 1 corresponds to a shale gas extraction well. The wet gas outlet pipes 4 of multiple desanding separators 1 are connected to the wet gas inlet pipes 12 of the gravity separator 9. Each wet gas outlet pipe 4 of multiple desanding separators 1 is equipped with a first flow meter 16 and a check valve 17. The check valve 17 is located downstream of the corresponding first flow meter 16. The first flow meter 16 is electrically connected to the controller and is used to detect the flow rate of wet gas discharged from the corresponding desanding separator 1. Specifically, the first flow meter 16 is an orifice plate flow meter, which has high detection accuracy. The check valve 17 prevents wet gas from returning to the desanding separator 1. By using multiple desanding separators 1 in conjunction with one gravity separator 9, simultaneous extraction of multiple shale gas wells can be achieved. At the same time, the desanding separators 1 integrate multiple functions into one unit, which can effectively reduce the footprint.

[0030] Reference Figure 1Multiple desand separators 1 are connected by connecting pipes 18 via their feed gas inlet pipes 2. The connecting pipes 18 are located downstream of the pressure regulating valve 5. The connecting pipes 18 help balance the pressure and flow fluctuations of the feed gas from different wells or branches, ensuring that multiple desand separators 1 can operate in parallel and evenly. Simultaneously, it allows for efficient processing of multiple desand separators 1 from a single well, as needed. In this application, two desand separators 1 are provided; in other embodiments, the number of desand separators 1 can be set as needed.

[0031] Reference Figure 1 To improve system integration, the processing system also includes a skid (not shown in the figure). The gravity separator 9, the controller, and multiple sand separators 1 are all fixedly integrated on the skid, which facilitates the overall installation and transportation of the system.

[0032] The implementation principle of the processing system in Embodiment 1 of this application is as follows: When the system starts working, the controller drives the pressure regulating valves 5 of multiple desand separators 1 to open, and closes the first sand discharge valves 6 of multiple desand separators 1 and the second sand discharge valves 15 of gravity separators 9. Then, the wellhead raw gas enters the desand separator 1 through the raw gas inlet pipe 2. The first pressure measuring element 7 measures the pressure inside the corresponding desand separator 1. The controller dynamically adjusts the opening of the corresponding pressure regulating valve 5 according to the pressure value detected by the first pressure measuring element 7. Specifically, the controller sets the preset pressure value inside the desand separator 1 to P and the pressure stabilization range to P1-P2, where P=(P1+P2) / 2. P1 and P2 are set according to actual needs; after the first pressure measuring element 7 detects that the pressure value reaches the preset pressure value P for the first time, the system reaches the first equilibrium state; when the system reaches the first equilibrium state, if the pressure value detected by the first pressure measuring element 7 is within the pressure stabilization range P1-P2, the controller drives the pressure regulating valve 5 to maintain the current opening; when the system reaches the first equilibrium state, if the pressure value detected by the first pressure measuring element 7 is less than the pressure stabilization range P1-P2, the controller drives the pressure regulating valve 5 to increase the opening; when the system reaches the first equilibrium state, if the pressure value detected by the first pressure measuring element 7 is greater than the pressure stabilization range P1-P2, the controller drives the pressure regulating valve 5 to decrease the opening. Furthermore, the controller sets the pressure change gradient within the sand separator 1 to P0, where P0 = P2 - P1. When the system reaches the first equilibrium state, if the pressure value detected by the first pressure measuring element 7 decreases by one P0, the controller drives the opening of the pressure regulating valve 5 to increase by 10%. If the pressure value detected by the first pressure measuring element 7 decreases by five P0, the controller drives the pressure regulating valve 5 to fully open. When the system reaches the first equilibrium state, if the pressure value detected by the first pressure measuring element 7 increases by one P0, the controller drives the opening of the pressure regulating valve 5 to decrease by 10%. If the pressure value detected by the first pressure measuring element 7 increases by five P0, the controller drives the pressure regulating valve 5 to fully close, thereby achieving dynamic adjustment of the opening of the pressure regulating valve 5.

[0033] After the raw material gas in the sand separator 1 is processed, the moisture is discharged through the moisture outlet pipe 4 to the moisture inlet pipe 12, and then enters the gravity separator 9. The first liquid level gauge 8 detects the liquid level height in the corresponding sand separator 1. When the liquid level height detected by the first liquid level gauge 8 reaches the first preset value, the controller drives the first sand discharge valve 6 to open. The sand-containing liquid phase in the sand separator 1 is discharged to the external sewage pipe through the corresponding first liquid phase outlet pipe 3. The first preset value is 30% of the height of the sand separator 1 cylinder. Then the controller dynamically adjusts the opening degree of the first sand discharge valve 6 according to the liquid level height detected by the first liquid level gauge 8.

[0034] Specifically, the controller sets H0 to 20% of the height of the sand separator 1 cylinder, H1 to 30% of the height of the sand separator 1 cylinder, H2 to 50% of the height of the sand separator 1 cylinder, H3 to 80% of the height of the sand separator 1 cylinder, H1-H2 to the safe range of the liquid level in the sand separator 1, H0 to the low alarm threshold of the liquid level in the sand separator 1, and H3 to the high alarm threshold of the liquid level in the sand separator 1. During system start-up and pressure boosting or pressure stabilization, when the first level gauge 8 detects that the liquid level inside the sand separator 1 reaches H1, the controller drives the first sand discharge valve 6 to slowly open; when the first level gauge 8 detects that the sand separator... When the liquid level in separator 1 is within the safe range of H1-H2, the controller uses a PID fuzzy control algorithm to dynamically adjust the opening of the first sand discharge valve 6. When the first level gauge 8 detects that the liquid level in separator 1 is within H2-H3, the controller drives the opening of the first sand discharge valve 6 to be adjusted to 50%. During the liquid accumulation process, when the first level gauge 8 detects that the liquid level in separator 1 reaches H3, the controller drives the first sand discharge valve 6 to be fully open. During the liquid discharge process, when the first level gauge 8 detects that the liquid level in separator 1 is lower than H0, the controller drives the first sand discharge valve 6 to be fully closed, thereby realizing the dynamic adjustment of the opening of the first sand discharge valve 6.

[0035] After the moisture entering the gravity separator 9 is separated, the treated gas is discharged from the dry gas outlet pipe 14 to the collection and transportation pipeline. The second liquid level gauge 10 detects the liquid level inside the gravity separator 9. When the second liquid level gauge 10 detects that the liquid level inside the gravity separator 9 has reached the second preset value, the controller drives the second sand discharge valve 15 to open, and the liquid phase inside the gravity separator 9 is discharged from the second liquid phase outlet pipe 13 to the external sewage pipe. The second preset value is 30% of the height of the gravity separator 9 cylinder.

[0036] Then, the controller dynamically adjusts the opening of the second sand discharge valve 15 based on the liquid level height detected by the second level gauge 10. Specifically, the controller sets 20% of the height of the gravity separator 9 cylinder as h0, 30% as h1, 50% as h2, 80% as h3, the safe liquid level range in the gravity separator 9 as h1-h2, the low alarm threshold for the liquid level in the gravity separator 9 as h0, and the high alarm threshold for the liquid level in the gravity separator 9 as h3. When the second level gauge 10 detects that the liquid level in the gravity separator 9 has risen to h1, the controller drives the second sand discharge valve 15 to open and... The opening degree is 5%-10%; when the liquid level height detected by the second liquid level gauge 10 is within h1-h2, the controller drives the opening degree of the second sand discharge valve 15 to adjust to 10%; during the liquid accumulation process, when the liquid level height detected by the second liquid level gauge 10 is within h2-h3, the controller drives the opening degree of the second sand discharge valve 15 to adjust to 20%; when the liquid level height detected by the second liquid level gauge 10 is greater than h3, the controller drives the opening degree of the second sand discharge valve 15 to adjust to 50%-100%; during the liquid discharge process, when the liquid level height detected by the second liquid level gauge 10 is lower than h0, the controller drives the second sand discharge valve 15 to close, thereby realizing the dynamic adjustment of the second sand discharge valve 15.

[0037] This application also discloses a multi-functional adaptive processing technology for centralized surface extraction of shale gas. The multi-functional adaptive processing technology for centralized surface extraction of shale gas, using the above-mentioned processing system, further includes the following steps: Step 1: When the system starts working, the controller drives the pressure regulating valve 5 to open and the first sand discharge valve 6 and the second sand discharge valve 15 to close. The wellhead raw gas enters the corresponding desand separator 1 through the raw gas inlet pipe 2. The first pressure measuring element 7 measures the pressure inside the desand separator 1. The controller adjusts the opening of the corresponding pressure regulating valve 5 according to the pressure value detected by the first pressure measuring element 7. Step 2: After the raw material gas in the sand separator 1 is processed, the moisture is discharged to the moisture inlet pipe 12 through the moisture outlet pipe 4. Step 3: The first level gauge 8 detects the liquid level in the corresponding sand separator 1. When the liquid level detected by the first level gauge 8 reaches the first preset value, the controller drives the first sand discharge valve 6 to open, and the sand-containing liquid phase in the sand separator 1 is discharged to the external sewage pipe through the corresponding first liquid phase outlet pipe 3. Step 4: The controller dynamically adjusts the opening of the first sand discharge valve 6 based on the liquid level height detected by the first liquid level gauge 8; Step 5: After the moisture enters the gravity separator 9 from the moisture inlet pipe 12 and is separated, the treated gas is discharged from the dry gas outlet pipe 14 to the collection and transmission pipeline. Step 6: The second level gauge 10 detects the liquid level inside the gravity separator 9. When the liquid level detected by the second level gauge 10 reaches the second preset value, the controller drives the second sand discharge valve 15 to open, and the liquid phase inside the gravity separator 9 is discharged from the second liquid phase outlet pipe 13 to the external drain pipe. Step 7: The controller dynamically adjusts the opening of the second sand discharge valve 15 according to the liquid level height detected by the second liquid level gauge 10.

[0038] Further, in step 1, the controller adjusts the opening of the pressure regulating valve 5 according to the pressure value detected by the first pressure measuring element 7. This includes the controller setting the preset pressure value in the sand separator 1 to P and the stabilization range in the sand separator 1 to P1-P2, where P = (P1 + P2) / 2. After the first pressure measuring element 7 detects that the pressure value reaches the preset pressure value P for the first time, the system reaches the first equilibrium state. When the system reaches the first equilibrium state, if the pressure value detected by the first pressure measuring element 7 is within the stabilization range P1-P2, the controller drives the pressure regulating valve 5 to maintain its current opening. When the system reaches the first equilibrium state, if the pressure value detected by the first pressure measuring element 7 is less than the stabilization range P1-P2, the controller drives the opening of the pressure regulating valve 5 to increase. When the system reaches the first equilibrium state, if the pressure value detected by the first pressure measuring element 7 is greater than the stabilization range P1-P2, the controller drives the opening of the pressure regulating valve 5 to decrease.

[0039] Furthermore, the controller sets the pressure change gradient within the sand separator 1 to P0, where P0 = P2 - P1. When the system reaches the first equilibrium state, if the pressure value detected by the first pressure measuring element 7 decreases by one P0, the controller drives the opening of the pressure regulating valve 5 to increase by 10%. If the pressure value detected by the first pressure measuring element 7 decreases by five P0, the controller drives the pressure regulating valve 5 to fully open. When the system reaches the first equilibrium state, if the pressure value detected by the first pressure measuring element 7 increases by one P0, the controller drives the opening of the pressure regulating valve 5 to decrease by 10%. If the pressure value detected by the first pressure measuring element 7 increases by five P0, the controller drives the pressure regulating valve 5 to fully close.

[0040] Further, in step 4, the controller adjusts the opening of the first sand discharge valve 6 according to the liquid level height detected by the first level gauge 8. This includes setting the controller to H0 for 20% of the height of the sand separator 1 cylinder, H1 for 30% of the height of the sand separator 1 cylinder, H2 for 50% of the height of the sand separator 1 cylinder, H3 for 80% of the height of the sand separator 1 cylinder, H1-H2 for the safe liquid level range in the sand separator 1, H0 for the low liquid level alarm threshold in the sand separator 1, and H3 for the high liquid level alarm threshold in the sand separator 1. Here, H1 is a first preset value. During system start-up and pressure increase or during pressure stabilization, when the first level gauge 8 detects that the liquid level inside the sand separator 1 reaches H1, the controller drives the first sand discharge valve 6 to open slowly; when the first level gauge 8 detects... When the liquid level in the sand separator 1 is within the safe range of H1-H2, the controller dynamically adjusts the opening of the first sand discharge valve 6 using a PID fuzzy control algorithm. When the first level gauge 8 detects that the liquid level in the sand separator 1 is within H2-H3, the controller drives the opening of the first sand discharge valve 6 to 50%. During the liquid accumulation process, when the first level gauge 8 detects that the liquid level in the sand separator 1 reaches H3, the controller drives the first sand discharge valve 6 to fully open. During the liquid discharge process, when the first level gauge 8 detects that the liquid level in the sand separator 1 is lower than H0, the controller drives the first sand discharge valve 6 to fully close. This helps to control the liquid level inside the sand separator 1 within a safe range, ensuring sand removal efficiency and preventing non-gas phase from entering the gas transmission pipeline, thus ensuring the normal operation of the system. The PID fuzzy control algorithm is existing technology and will not be elaborated upon here. In other embodiments, when the first level gauge 8 detects that the liquid level in the sand separator 1 is within the safe range of H1-H2, the controller can also drive the first sand discharge valve 6 to maintain the current opening.

[0041] Further, in step 7, the controller adjusts the opening of the second sand discharge valve 15 according to the liquid level height detected by the second level gauge 10. This includes setting the following parameters for the controller: 20% of the height of the gravity separator 9 cylinder as h0; 30% of the height of the gravity separator 9 cylinder as h1; 50% of the height of the gravity separator 9 cylinder as h2; 80% of the height of the gravity separator 9 cylinder as h3; the safe liquid level range in the gravity separator 9 as h1-h2; the low alarm threshold for the liquid level in the gravity separator 9 as h0; and the high alarm threshold for the liquid level in the gravity separator 9 as h3. Here, h1 is a second preset value. When the second level gauge 10 detects that the liquid level in the gravity separator 9 has risen to h1, the controller drives the second sand discharge valve 15 to open. The opening degree is 5%-10%; when the second level gauge 10 detects that the liquid level in the gravity separator 9 is within h1-h2, the controller drives the opening degree of the second sand discharge valve 15 to adjust to 10%; during the liquid accumulation process, when the second level gauge 10 detects that the liquid level in the gravity separator 9 is within h2-h3, the controller drives the opening degree of the second sand discharge valve 15 to adjust to 20%; when the second level gauge 10 detects that the liquid level in the gravity separator 9 is greater than h3, the controller drives the opening degree of the second sand discharge valve 15 to adjust to 50%-100%; during the liquid discharge process, when the second level gauge 10 detects that the liquid level in the gravity separator 9 is lower than h0, the controller drives the second sand discharge valve 15 to close.

[0042] Example 2:

[0043] Reference Figure 1 The difference between this embodiment and embodiment 1 is that the processing system also includes a buffer tank 19, which has a liquid phase inlet pipe 20 and a third liquid phase outlet pipe 21. The second liquid phase outlet pipe 13 of the gravity separator 9 is connected to the liquid phase inlet pipe 20. The liquid phase inlet pipe 20 is located downstream of the second sand discharge valve 15. The third liquid phase outlet pipe 21 is used to connect to an external sewage pipe. A first regulating valve 22 is installed on the third liquid phase outlet pipe 21.

[0044] Reference Figure 2 Each sand separator 1 has a backflushing pipe 23 connected to its bottom. Multiple backflushing pipes 23 are connected to a buffer tank 19 via a backflushing pump 26. A second regulating valve 24 is installed at the end of the backflushing pipe 23 near the corresponding sand separator 1. The backflushing pump 26, the first regulating valve 22, and the second regulating valve 24 are all electrically connected to the controller. A branch pipe 25 is connected between the backflushing pipe 23 and the first liquid phase outlet pipe 3 of the corresponding sand separator 1. The branch pipe 25 is located upstream of the corresponding first sand discharge valve 6.

[0045] Reference Figure 2 Figure 2A third level gauge 27 is installed on the buffer tank 19. The third level gauge 27 is used to detect the liquid level in the buffer tank 19. The third level gauge 27 is electrically connected to the controller. The controller adjusts the opening of the first regulating valve 22 according to the liquid level detected by the third level gauge 27 so that the liquid level in the buffer tank 19 is within the preset buffer range. Specifically, the preset buffer range of the buffer tank 19 is set as needed to ensure that enough liquid can be drawn into the backflushing pipe 23 when backflushing is required. In this embodiment, the preset buffer range is 30%-60% of the tank height of the buffer tank 19.

[0046] The implementation principle of Embodiment 2 of this application is as follows: When the controller detects that the opening of the pressure regulating valve 5 of the sand separator 1 decreases and the opening of the first sand discharge valve 6 increases, but the liquid level height detected by the first liquid level gauge 8 does not decrease or even increases, it proves that the bottom of the sand separator 1 is blocked. At this time, the controller drives the backwash pump 26 to work and opens the second regulating valve 24 at the same time. The backwash pump 26 draws the liquid phase buffered in the buffer tank 19 into the backwash pipe 23. Then, through the backwash pipe 23, the sediment at the bottom of the sand separator 1 cylinder can be backwashed. Through the branch pipe 25, the end of the first liquid phase outlet pipe 3 near the corresponding sand separator 1 can be backwashed. At the same time, the first sand discharge valve 6 of multiple sand separators 1 is fully opened, which helps to eliminate the blockage at the bottom of the sand separator 1 or the blockage in the first liquid phase outlet pipe 3, ensuring the sand removal efficiency and normal operation of the system. The liquid phase discharged by the gravity separator 9 will not introduce new media and affect the raw material gas separation, and can also improve resource utilization. There is no need to introduce external media, saving costs.

[0047] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A multi-functional adaptive processing system for centralized surface extraction of shale gas, characterized in that, include: A desand separator (1) has a raw gas inlet pipe (2), a first liquid phase outlet pipe (3) and a wet gas outlet pipe (4). The raw gas inlet pipe (2) is used to connect with the wellhead to input raw gas. A pressure regulating valve (5) is installed on the raw gas inlet pipe (2). The first liquid phase outlet pipe (3) is used to connect with an external sewage pipe. A first sand discharge valve (6) is installed on the first liquid phase outlet pipe (3). The desand separator (1) is used to remove sand particles and free liquid to output wet gas from the wet gas outlet pipe (4). The first pressure measuring element (7) is used to measure the internal pressure of the sand separator (1); The first liquid level gauge (8) is used to measure the liquid level height inside the sand separator (1); The controller is electrically connected to the sand separator (1), pressure regulating valve (5), first sand discharge valve (6), first pressure measuring element (7) and first level gauge (8). The controller adjusts the opening of the pressure regulating valve (5) according to the pressure value detected by the first pressure measuring element (7), and adjusts the opening of the first sand discharge valve (6) according to the liquid level height value detected by the first level gauge (8).

2. The multifunctional adaptive processing system for centralized shale gas surface extraction according to claim 1, characterized in that: The processing system also includes a gravity separator (9), a second level gauge (10), and a second pressure measuring device (11). The gravity separator (9) has a wet gas inlet pipe (12), a second liquid phase outlet pipe (13), and a dry gas outlet pipe (14). The wet gas inlet pipe (12) is connected to the wet gas outlet pipe (4). The second liquid phase outlet pipe (13) is used to connect to an external sewage pipe. A second sand discharge valve (15) is installed on the second liquid phase outlet pipe (13). The dry gas outlet pipe (14) is used to connect to an external collection and transportation pipeline. (9) is used for gas-liquid separation to output processed gas from dry gas outlet pipe (14). The second liquid level gauge (10) is used to measure the liquid level height inside the gravity separator (9). The second pressure measuring element (11) is used to measure the internal pressure of the gravity separator (9). The gravity separator (9), the second liquid level gauge (10), the second pressure measuring element (11) and the second sand discharge valve (15) are all electrically connected to the controller. The controller adjusts the opening degree of the second sand discharge valve (15) according to the liquid level height value detected by the second liquid level gauge (10).

3. The multifunctional adaptive processing system for centralized shale gas surface extraction according to claim 2, characterized in that: Multiple sand separators (1) are provided. The moisture outlet pipes (4) of multiple sand separators (1) are connected to the moisture inlet pipe (12). A first flow meter (16) and a check valve (17) are installed on the moisture outlet pipes (4) of multiple sand separators (1). The check valve (17) is located downstream of the corresponding first flow meter (16).

4. The multifunctional adaptive processing system for centralized surface extraction of shale gas according to claim 3, characterized in that: A connecting pipe (18) is connected between the raw material gas inlet pipes (2) of the multiple sand separators (1), and the connecting pipe (18) is located downstream of the pressure regulating valve (5).

5. A multi-functional adaptive processing system for centralized shale gas surface extraction according to claim 2, characterized in that: The processing system also includes a skid, on which the sand separator (1), gravity separator (9) and controller are all integrated.

6. A multi-functional adaptive processing system for centralized shale gas surface extraction according to any one of claims 2-5, characterized in that: The processing system also includes a buffer tank (19), which has a liquid phase inlet pipe (20) and a third liquid phase outlet pipe (21). The second liquid phase outlet pipe (13) is connected to the liquid phase inlet pipe (20), and the third liquid phase outlet pipe (21) is used to connect to an external sewage pipe. A first regulating valve (22) is installed on the third liquid phase outlet pipe (21). A backflushing pipe (23) is connected to the bottom of the sand separator (1). The backflushing pipe (23) is connected to the buffer tank (19) through a backflushing pump (26). A second regulating valve (24) is installed on the backflushing pipe (23). The backflushing pump (26), the first regulating valve (22), and the second regulating valve (24) are all electrically connected to the controller. A branch pipe (25) is connected between the backflushing pipe (23) and the first liquid phase outlet pipe (3). The branch pipe (25) is located upstream of the first sand discharge valve (6).

7. A multi-functional adaptive processing technology for centralized surface extraction of shale gas, using the processing system described in any one of claims 2-6, characterized in that, Includes the following steps: When the system starts working, the controller drives the pressure regulating valve (5) to open and the first sand discharge valve (6) and the second sand discharge valve (15) to close. The wellhead raw gas enters the desand separator (1) through the raw gas inlet pipe (2). The first pressure measuring element (7) measures the pressure inside the desand separator (1). The controller adjusts the opening of the pressure regulating valve (5) according to the pressure value detected by the first pressure measuring element (7). After the raw material gas in the sand separator (1) is processed, the moisture is discharged to the moisture inlet pipe (12) through the moisture outlet pipe (4); The liquid level in the sand separator (1) is detected by the first liquid level gauge (8). When the first liquid level gauge (8) detects that the liquid level in the sand separator (1) reaches the first preset value, the controller drives the first sand discharge valve (6) to open, and the sand-containing liquid phase in the sand separator (1) is discharged to the external sewage pipe through the first liquid phase outlet pipe (3). The controller adjusts the opening degree of the first sand discharge valve (6) according to the liquid level height detected by the first liquid level gauge (8); The moisture entering the gravity separator (9) from the moisture inlet pipe (12) is separated and treated, and the treated gas is discharged from the dry gas outlet pipe (14). The second level gauge (10) detects the liquid level inside the gravity separator (9). When the second level gauge (10) detects that the liquid level inside the gravity separator (9) reaches the second preset value, the controller drives the second sand discharge valve (15) to open, and the liquid phase inside the gravity separator (9) is discharged from the second liquid phase outlet pipe (13) to the external sewage pipe. The controller adjusts the opening of the second sand discharge valve (15) based on the liquid level height detected by the second liquid level gauge (10).

8. The processing technology according to claim 7, characterized in that: The controller adjusts the opening of the pressure regulating valve (5) according to the pressure value detected by the first pressure measuring element (7). This includes setting the preset pressure value P in the sand separator (1) and the stabilization range P1-P2, where P = (P1+P2) / 2. After the first pressure measuring element (7) detects that the pressure value reaches the preset pressure value P for the first time, the system reaches the first equilibrium state. When the system reaches the first equilibrium state, if the pressure value detected by the first pressure measuring element (7) is within the stabilization range P1-P2, the controller drives the pressure regulating valve (5) to maintain its current opening. When the system reaches the first equilibrium state, if the pressure value detected by the first pressure measuring element (7) is less than the stabilization range P1-P2, the controller drives the pressure regulating valve (5) to increase its opening. When the system reaches the first equilibrium state, the first pressure measuring element... (7) When the detected pressure value is greater than the pressure stabilization range P1-P2, the controller drives the pressure regulating valve (5) to decrease its opening. The controller sets the pressure change gradient of the sand separator (1) to P0, where P0 = P2-P1. When the system reaches the first equilibrium state, when the pressure value detected by the first pressure measuring element (7) decreases by one P0, the controller drives the pressure regulating valve (5) to increase its opening by 10%. When the pressure value detected by the first pressure measuring element (7) decreases by five P0, the controller drives the pressure regulating valve (5) to fully open. When the system reaches the first equilibrium state, when the pressure value detected by the first pressure measuring element (7) increases by one P0, the controller drives the pressure regulating valve (5) to decrease its opening by 10%. When the pressure value detected by the first pressure measuring element (7) increases by five P0, the controller drives the pressure regulating valve (5) to fully close.

9. The processing technology according to claim 7, characterized in that: The controller adjusts the opening of the first sand discharge valve (6) according to the liquid level height detected by the first level gauge (8). This includes setting the controller to 20% of the height of the sand separator (1) cylinder as H0, 30% as H1, 50% as H2, 80% as H3, the safe range of the liquid level in the sand separator (1) as H1-H2, the low alarm threshold of the liquid level in the sand separator (1) as H0, and the high alarm threshold of the liquid level in the sand separator (1) as H3. Here, H1 is the first preset value. During the system start-up and pressure increase process or the pressure stabilization process, when the first level gauge (8) detects the liquid level inside the sand separator (1)... When the liquid level reaches H1, the controller drives the first sand discharge valve (6) to open; when the first level gauge (8) detects that the liquid level in the sand separator (1) is within the safe range of H1-H2, the controller uses a PID fuzzy control algorithm to adjust the opening of the first sand discharge valve (6); when the first level gauge (8) detects that the liquid level in the sand separator (1) is within H2-H3, the controller drives the opening of the first sand discharge valve (6) to be adjusted to 50%; when the first level gauge (8) detects that the liquid level in the sand separator (1) is higher than H3, the controller drives the first sand discharge valve (6) to be fully open; when the first level gauge (8) detects that the liquid level in the sand separator (1) is lower than H0, the controller drives the first sand discharge valve (6) to be fully closed.

10. The processing technology according to claim 7, characterized in that: The controller adjusts the opening of the second sand discharge valve (15) according to the liquid level height detected by the second level gauge (10). This includes setting the following parameters: 20% of the height of the gravity separator (9) cylinder as h0; 30% as h1; 50% as h2; 80% as h3; a safe liquid level range in the gravity separator (9) of h1-h2; a low-level alarm threshold for the liquid level in the gravity separator (9) of h0; and a high-level alarm threshold for the liquid level in the gravity separator (9) of h3. Here, h1 is a second preset value. When the second level gauge (10) detects that the liquid level in the gravity separator (9) rises to h1, the controller drives the second sand discharge valve (15) to open. The controller opens the second sand discharge valve (15) to 10% when the second level gauge (10) detects that the liquid level in the gravity separator (9) is within h1-h2; when the second level gauge (10) detects that the liquid level in the gravity separator (9) is within h2-h3, the controller drives the second sand discharge valve (15) to 20%; when the second level gauge (10) detects that the liquid level in the gravity separator (9) is greater than h3, the controller drives the second sand discharge valve (15) to 50%-100%; when the second level gauge (10) detects that the liquid level in the gravity separator (9) is lower than h0, the controller drives the second sand discharge valve (15) to close.

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