Pipeline gas hydrogen sulfide detector

Abstract

The utility model relates to the technical field of pipeline pressurized gas detection equipment, in particular to a pipeline gas hydrogen sulfide detector which comprises a piston cavity, a piston is arranged in the piston cavity in a sliding mode, one end of the piston is connected with a driving mechanism capable of driving the piston to move, and the end, away from the driving mechanism, of the piston cavity is respectively connected with a first pipeline and a second pipeline. The first pipeline is provided with a control valve a, the other end of the second pipeline is connected with the side face of the piston cavity, the second pipeline is sequentially provided with a control valve c, an air pump, an H2S sensor and a check valve a, the side face of the piston cavity is further connected with a third pipeline, the third pipeline is connected with a control valve b, and the first pipeline is provided with a pressure sensor a. And a pressure sensor b is mounted on the piston cavity. The device has the characteristic of high-speed detection, is particularly suitable for an oil well pipeline hydrogen sulfide treatment scheme provided by an oil field at present, and meets the requirement of multi-point rapid detection.

Description

Technical Field

[0001] The utility model relates to the technical field of pipeline pressurized gas detection equipment, in particular to a pipeline gas hydrogen sulfide detector. Background Technique

[0002] The oil and gas wells in oil fields contain toxic H2S gas. If it leaks, it will not only affect the enterprise production but also cause harm to personal safety. In order to ensure production and personnel safety, enterprises need to regularly detect the gas in oil and gas well pipelines.

[0003] The currently common method is that workers wear protective clothing and carry special containers to each oil and gas well head to take samples for detection. Due to factors such as frequent sampling, long distances, and complex environments, manual sampling not only has low efficiency, long time consumption, and high cost, but also has safety risks of gas leakage and harm to personnel.

[0004] In the prior art, the remote online method is used to detect the gas in the oil well head pipeline, which can solve the above problems. For example, the Chinese patent with the authorization announcement number of CN117948075B developed by the applicant discloses an integrated fluid control device for multi-scene applications, which can realize the remote automatic collection of the gas in the oil well pipeline. However, the gas in the oil well pipeline collected remotely automatically has a relatively high pressure, while the H2S sensors produced at home and abroad at present are only suitable for working in an atmospheric pressure environment, and the gas with a higher pressure cannot be directly detected by the H2S sensor.

[0005] In view of the above problems, the Chinese patent with the authorization announcement number of CN221628139U developed by the applicant discloses an intelligent online hydrogen sulfide detector for crude oil well head pipelines. The detection unit of this detector can reduce the pressure of the pipeline gas, so as to detect H2S in the depressurized pipeline gas, solve the problem that the H2S sensor cannot detect the high-pressure pipeline gas, and thus realize the remote monitoring of the hydrogen sulfide in the pipeline pressurized gas in real time. This hydrogen sulfide online detector adopts a functional cabin structure, reduces the pipeline gas to atmospheric pressure by means of vacuum pumping, and ensures the normal detection of the H2S sensor by means of adding oxygen-containing gas.

[0006] However, the structures and functions of the above prior art are separately set. Processes such as vacuum pumping, gas pressure reduction, oxygen-containing gas mixing, pressure control, detection, and reinjection need to be carried out separately. This not only reduces the detection rate and prolongs the entire detection process, but also increases the probability of failure due to more structures and components, and the overall structure volume is also relatively large, resulting in higher production and installation costs. In addition, since the volume of the functional cabin is fixed, when the pipeline gas pressure is relatively high or under certain extreme factors, the gas pressure in the functional cabin may be too high. Although the instrument has a pressure control function to perform secondary pressure reduction, the pressure reduction process will reduce the work efficiency and prolong the detection time, making the overall structure respond slowly. Summary of the Invention

[0007] The utility model is improved on the basis of the prior art and provides a pipeline gas hydrogen sulfide detector.

[0008] In order to solve the above technical problems, the utility model provides the following technical solutions:

[0009] A pipeline gas hydrogen sulfide detector includes a piston chamber, a piston is slidably arranged in the piston chamber, one end of the piston is connected with a driving mechanism capable of driving its movement, the end of the piston chamber far away from the driving mechanism is respectively connected with a first pipeline and a second pipeline, a control valve a is arranged on the first pipeline, the other end of the second pipeline is connected with the side surface of the piston chamber, a control valve c, an air pump, an H2S sensor and a check valve a are sequentially arranged on the second pipeline, a third pipeline is further connected to the side surface of the piston chamber, a control valve b is connected to the third pipeline, a pressure sensor a is arranged on the first pipeline, and a pressure sensor b is installed on the piston chamber.

[0010] In the above structure, by using the piston chamber structure and the principle of reciprocating movement of the piston, not only can the volume of the piston chamber be arbitrarily changed to control the pressure reduction, but also the processes of vacuum pumping, gas pressure reduction, mixing, detection and reinjection can be completed in this single structure of the piston chamber by using its suction or exhaust movement, reducing the failure rate while quickly detecting, and at the same time optimizing the overall structure of the detector, making the overall structure more compact and concise.

[0011] A flow limiting valve is arranged on the first pipeline, and the flow limiting valve is arranged between the control valve a and the piston chamber. The first pipeline is used to connect the pipeline gas of the oil field. The flow limiting valve can not only control the size of the gas flow rate and can be preset in advance to prevent the gas flow rate from being too large and avoid the gas pressure entering the piston chamber exceeding the specified value.

[0012] A branch pipeline is arranged in parallel on the first pipeline, and a check valve b is installed on the branch pipeline. The check valve b is arranged in parallel with the flow limiting valve. The purpose of connecting the flow limiting valve in parallel with the check valve b is to improve the gas reinjection speed.

[0013] The driving mechanism can be selected from the following two structural forms:

[0014] One is that the driving mechanism includes an electric cylinder, the electric cylinder is fixedly arranged outside the piston chamber, and the output end of the electric cylinder movably passes through the piston chamber and is fixedly connected with the piston.

[0015] The other is that the driving mechanism includes a servo motor, the servo motor is connected with a gear set, the gear set is connected with a nut, the nut is rotatably connected outside the piston chamber, a ball screw is threadedly sleeved on the nut, and the ball screw penetrates through the piston chamber and is rotatably connected with the piston.

[0016] To ensure the sealing performance between the piston and the piston chamber, a sealing ring is provided between the piston and the piston chamber.

[0017] The control valves a, c, and b are all selected as solenoid valves.

[0018] The beneficial effects achieved by the present utility model are as follows:

[0019] The present utility model has the detection feature of high speed, and is particularly suitable for the hydrogen sulfide treatment plan of oil well pipelines currently proposed in oil fields, meeting the needs of rapid detection at multiple positions.

[0020] The volume in the piston chamber of the present utility model is variable. By using the piston chamber structure and the principle of piston reciprocating motion, not only can the volume of the piston chamber be arbitrarily changed to control pressure reduction, but also by using its suction or exhaust motion, processes such as vacuum pumping, gas pressure reduction, oxygen-containing gas mixing, detection, and reinjection are completed together in the same structure, achieving rapid detection. At the same time, the failure rate is reduced, and cost can also be reduced and efficiency increased.

[0021] In the present utility model, a flow limiting valve is provided on the first pipeline. The flow limiting valve can not only control the size of the gas flow, but also can be preset in advance to prevent the gas flow from being too large, avoiding the gas pressure entering the piston chamber from exceeding the specified value, thereby avoiding the cumbersome process of secondary pressure reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings are used to provide a further understanding of the present utility model, and constitute a part of the specification. Together with the embodiments of the present utility model, they are used to explain the present utility model, and do not constitute a limitation to the present utility model. In the drawings:

[0023] Figure 1 is a schematic structural diagram of Embodiment 1 of the present utility model (evacuation / gas reinjection state);

[0024] Figure 2 is a schematic structural diagram of Embodiment 1 of the present utility model (after vacuum pumping, introducing air and pipeline gas successively);

[0025] Figure 3 is a schematic structural diagram of Embodiment 1 of the present utility model (pressure reduction state);

[0026] Figure 4 is a schematic structural diagram of Embodiment 2 of the present utility model.

[0027] In the figure: 1. Pressure sensor a; 2. Control valve a; 3. Flow limiting valve; 4. Control valve c; 5. Air pump; 6. Second pipeline; 7. H2S sensor; 8. Check valve a; 9. Piston chamber; 10. Electric cylinder; 11. First pipeline; 12. Branch pipeline; 13. Check valve b; 14. Pressure sensor b; 15. Control valve b; 16. Third pipeline; 17. Sealing ring; 18. Piston; 19. Bearing; 20. Ball screw; 21. Nut; 22. Gear set; 23. Servo motor. Specific implementation mode

[0028] The preferred embodiments of the present utility model will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present utility model, and are not used to limit the present utility model.

[0029] Embodiment 1:

[0030] As Figure 1 , Figure 2 , Figure 3 shown, a pipeline gas hydrogen sulfide detector includes a piston chamber 9, in which a piston 18 is slidably arranged, and one end of the piston 18 is connected with a driving mechanism capable of driving it to linearly move in the piston chamber 9.

[0031] One end of the piston chamber 9 away from the driving mechanism is respectively connected with a first pipeline 11 and a second pipeline 6. A control valve a 2 is arranged on the first pipeline 11, and the first pipeline 11 is used to connect the pipeline gas at the wellhead of the oil and gas well.

[0032] The other end of the second pipeline 6 is connected to the side of the piston chamber 9 and is arranged as close as possible to the left end face of the piston chamber 9, and is communicated with the inside of the piston chamber 9 to form a circulation pipeline. A control valve c 4, an air pump 5, an H2S sensor 7 and a check valve a 8 are sequentially arranged on the second pipeline 6, and the check valve a 8 restricts the gas to only flow from the second pipeline 6 to the piston chamber 9.

[0033] The side of the piston chamber 9 is also connected with a third pipeline 16, and a control valve b 15 is connected to the third pipeline 16, and the third pipeline 16 is communicated with the external air.

[0034] A pressure sensor a 1 is arranged on the first pipeline 11. The function of the pressure sensor a 1 is to control the initial staying position of the piston 18 according to the pressure after determining the pipeline gas pressure.

[0035] A pressure sensor b 14 is installed on the piston chamber 9, and the pressure sensor b 14 is installed at one end of the piston chamber 9 close to the first pipeline 11.

[0036] A flow limiting valve 3 is arranged on the first pipeline 11, and the flow limiting valve 3 is arranged between the control valve a 2 and the piston chamber 9.

[0037] A branch pipe 12 is arranged in parallel on the first pipe 11. A check valve b 13 is installed on the branch pipe 12. The check valve b 13 controls the gas to flow only from the piston chamber 9 to the pipe gas direction. The check valve b 13 is arranged in parallel with the flow limiting valve 3. The purpose of arranging the flow limiting valve 3 in parallel with the check valve b 13 is to increase the gas reinjection speed, thereby increasing the working speed.

[0038] The driving mechanism includes an electric cylinder 10. The electric cylinder 10 is fixedly arranged outside the piston chamber 9. The output end of the electric cylinder 10 movably passes through the piston chamber 9 and is fixedly connected to the piston 18. The electric cylinder 10 can drive the piston 18 to move back and forth.

[0039] In order to ensure the sealing performance between the piston 18 and the left cavity of the piston chamber 9, a sealing ring 17 is arranged between the piston 18 and the piston chamber 9.

[0040] The control valve a 2, the control valve c 4 and the control valve b 15 are all selected as solenoid valves.

[0041] The working process of the utility model is as follows:

[0042] To ensure that there is no residual gas in the detector, evacuation is required first. First, the electric cylinder 10 of the driving mechanism is started, and the piston 18 is pushed forward (to the left in the attached drawing) to exhaust gas. The length of the electric cylinder 10 can be set. After the piston 18 is pushed forward to the end face of the piston chamber 9 (as Figure 1 shown), it stops working. At this time, the control valve a 2 is opened, and the residual gas is reinjected into the pipe gas through the check valve b 13 and the flow limiting valve 3;

[0043] After the control valve a 2 is closed, the electric cylinder 10 of the driving mechanism is started again. As Figure 2 shown, the piston 18 is pulled backward (to the right in the attached drawing), and at the same time the control valve b 15 is opened to inhale external air into the chamber. When inhaling external air, the control valve c 4 can be opened at the same time (the purpose of inhaling external air and opening the control valve c 4 is to thoroughly empty the system with air). Then the control valve b 15 and the control valve c 4 are closed, and the electric cylinder 10 of the driving mechanism is started again to push the piston 18 forward for gas reinjection. At the same time, the control valve a 2 is opened. After the flushing gas is reinjected into the pipe gas, the control valve a 2 is closed.

[0044] In order to limit the gas volume entering the pipe gas and facilitate later pressure reduction and pressure control, as Figure 2As shown, after the electric cylinder 10 of the driving mechanism is activated to move the piston 18 backward to the position of 1 / 20 to 1 / 2 of the chamber volume as the initial position, it stops (the determination of the initial position is based on the pressure detected by the pressure sensor a1. When the pressure sensor a1 detects a relatively large pipeline gas pressure, the volume formed at the initial position is smaller, which is convenient for subsequent pressure reduction to atmospheric pressure). Since no external gas enters the chamber, the initial chamber is in a vacuum state. Additionally, since the H2S sensor 7 requires oxygen for detection (the pipeline gas in the oil well pipeline does not contain oxygen), and the pipeline gas pressure is much greater than that of air, air needs to be injected into the initial chamber in advance. Therefore, the control valve b15 is opened to allow external air to enter the initial chamber through this valve. When the air entering the initial chamber reaches the same pressure as the outside (the pressure value of the pressure sensor b14), the control valve b15 is closed, and then the control valve a2 is opened. The pipeline gas enters the initial chamber through the flow limiting valve 3 and mixes with the air. When the incoming gas pressure reaches the set value (the pressure sensor b14 is used to detect the pressure), the control valve a2 is closed and the electric cylinder 10 is activated to move the piston 18 backward. As the piston 18 moves backward, as Figure 3 shown, the space where the mixed gas is located gradually increases, and the air pressure in the chamber also gradually decreases. When the air pressure reaches atmospheric pressure, the electric cylinder 10 is closed, and the control valve c4, the H2S sensor 7, and the air pump 5 are opened. The mixed gas in the chamber is circulated through the control valve c4, the air pump 5, the H2S sensor 7, and the check valve a8 while the hydrogen sulfide content is detected.

[0045] After the gas hydrogen sulfide detection is completed, the control valve c4, the H2S sensor 7, and the air pump 5 are closed, and then the electric cylinder 10 is activated to push the piston 18 for gas reinjection. At the same time, the control valve a2 is opened, and the detected gas is reinjected into the gas pipeline of the oil well through the check valve b13 and the flow limiting valve 3 by the control valve a2. After closing the control valve a2 and the electric cylinder 10, the detection ends.

[0046] If the pipeline gas pressure is greater than the air pressure after the piston 18 is compressed, causing the detected waste gas to be unable to be reinjected (comparing the pressure values of the pressure sensor a1 and the pressure sensor b14), the electric cylinder 10 can be activated to pull the piston 18 backward. At the same time, the control valve b15 is opened to inhale external air into the chamber, and then reinjection is carried out.

[0047] Combined with the description of the above work process, the utility model utilizes the structure of the piston chamber 9 and the reciprocating motion principle of the piston 18. It can not only arbitrarily change the volume of the piston chamber 9 to control and reduce the pressure, but also use its suction or exhaust motion to complete processes such as vacuum pumping, gas pressure reduction, oxygen-containing gas mixing, detection, and reinjection in the same structure, thereby enabling rapid detection.

[0048] Embodiment 2:

[0049] This embodiment is basically the same as Embodiment 1, except that the structure of the driving mechanism is different. For example, Figure 4 As shown, in this embodiment, the driving mechanism includes a servo motor 23. The output end of the servo motor 23 is connected to a gear set 22. The output end of the gear set 22 is connected to a nut 21. The servo motor 23 drives the nut 21 to rotate through the gear set 22. The nut 21 is rotatably connected to the outside of the piston chamber 9. The nut 21 is threadedly sleeved with a ball screw 20. The ball screw 20 penetrates through the piston chamber 9 and is rotatably connected to the piston 18 through a bearing 19. When the nut 21 rotates, it drives the ball screw 20 to rotate and at the same time perform a linear movement relative to the nut 21, thereby driving the piston 18 to move.

Claims

1. A pipeline gas hydrogen sulfide detector, characterized in that It includes a piston chamber (9), in which a piston (18) is slidably arranged. One end of the piston (18) is connected to a driving mechanism capable of driving its movement. The end of the piston chamber (9) far from the driving mechanism is respectively connected to a first pipeline (11) and a second pipeline (6). A control valve a (2) is arranged on the first pipeline (11). The other end of the second pipeline (6) is connected to the side of the piston chamber (9). A control valve c (4), an air pump (5), an H2S sensor (7) and a check valve a (8) are successively arranged on the second pipeline (6). A third pipeline (16) is also connected to the side of the piston chamber (9), and a control valve b (15) is connected to the third pipeline (16). A pressure sensor a (1) is arranged on the first pipeline (11), and a pressure sensor b (14) is installed on the piston chamber (9).

2. The pipeline gas hydrogen sulfide detector according to claim 1, characterized in that, A flow limiting valve (3) is arranged on the first pipeline (11), and the flow limiting valve (3) is arranged between the control valve a (2) and the piston chamber (9).

3. The pipeline gas hydrogen sulfide detector according to claim 2, wherein, A branch pipeline (12) is arranged in parallel on the first pipeline (11), and a check valve b (13) is installed on the branch pipeline (12). The check valve b (13) is arranged in parallel with the flow limiting valve (3).

4. The pipeline gas hydrogen sulfide detector according to claim 1, characterized in that, The driving mechanism includes an electric cylinder (10). The electric cylinder (10) is fixedly arranged outside the piston chamber (9). The output end of the electric cylinder (10) movably passes through the piston chamber (9) and is fixedly connected to the piston (18).

5. The pipeline gas hydrogen sulfide detector according to claim 1, characterized in that, The driving mechanism includes a servo motor (23). The servo motor (23) is connected to a gear set (22). The gear set (22) is connected to a nut (21). The nut (21) is rotatably connected outside the piston chamber (9). The nut (21) is threadedly sleeved with a ball screw (20). The ball screw (20) passes through the piston chamber (9) and is rotatably connected to the piston (18).

6. The pipeline gas hydrogen sulfide detector according to claim 1, wherein, A sealing ring (17) is arranged between the piston (18) and the piston chamber (9).

7. The pipeline gas hydrogen sulfide detector according to claim 1, wherein The control valve a (2), the control valve c (4) and the control valve b (15) are all selected as solenoid valves.

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