A device for taking a gas sample from a closed oil pipeline

Abstract

The utility model relates to a kind of oil pipeline closed gas sampling device, it is equipped with sampling tube and liquid storage cylinder, liquid level controller and the sampling tube equipped with liquid level transmitter are installed in liquid storage cylinder, liquid level controller is electrically connected with audible and visual alarm, and liquid level controller, liquid level transmitter and audible and visual alarm are connected with portable power supply;Overflow valve, communication pipe and back injection plug are installed in the cylinder body of liquid storage cylinder;Liquid inlet pipe equipped with liquid inlet valve and gas inlet pipe equipped with water valve and sampling valve are connected with upper end cover, and liquid level transmitter is loaded into sampling tube by upper end cover;Liquid inlet pipe can be connected with sampling valve in oil pipeline, and gas inlet pipe can be sequentially connected with colorimetric tube and negative pressure sampler;Liquid return pipe is equipped with liquid return valve and vent valve, and one end is connected with liquid inlet pipe, the other end is connected with lower end cover and communication pipe equipped with connecting pipe valve.

Description

Technical Field

[0001] This utility model relates to a gas sampling device for oil pipelines in the petroleum industry, specifically a closed gas sampling device for oil pipelines. Background Technology

[0002] Oil wells contain varying concentrations of hydrogen sulfide gas. To determine the hydrogen sulfide content, it is necessary to periodically collect hydrogen sulfide gas from the associated gas produced during the oil well production process for gas sample analysis. Currently used hydrogen sulfide sampling devices have the following problems: 1. When using existing samplers to obtain hydrogen sulfide gas from associated gas in crude oil at the wellhead, in order to obtain accurate gas samples, the air in the sampler needs to be pre-emptively replaced and discharged by on-site operators. This pre-emptive replacement and discharge method may result in sampling and testing before the air in the sampler has been completely replaced. According to feedback from sampling personnel, the test values ​​of several gas samples obtained consecutively at the wellhead differed significantly.

[0003] 2. After sampling, the waste liquid needs to be recycled. In order to protect the environment, the recycled waste liquid is troublesome to dispose of and can also generate hazardous waste disposal costs.

[0004] 3. When treating waste liquid, the sample gas obtained is filtered through water and then released into the air, which cannot guarantee that hydrogen sulfide will be completely absorbed.

[0005] 4. For oil wells with high water content and low gas volume, the existing sampler has insufficient volume and cannot obtain a sufficient amount of gas sample, resulting in sampling difficulties.

[0006] To ensure the accuracy of the gas samples taken, prevent environmental pollution, and reduce the amount of hazardous waste to be treated, it is necessary to develop a wellhead-sealed gas sampling device to achieve closed sampling.

[0007] To address the aforementioned issues, on-site staff have undertaken extensive work and achieved some positive results. Following a search, the following related technologies have been identified: Patent application number 202420569302.X discloses a fully enclosed gas sampling device for oil wellheads. A gas sampling device and a hydraulic pump are installed on the upper surface of the sampling device's base. The bottom of the gas sampling device is connected to a sampling valve via a sampling pipe, and the top of the gas sampling device is connected to the input end of a gas buffer via a pipeline and a control valve. The output end of the gas buffer is connected to the inlet of a gas sampling bag via a pipeline, and the outlet of the gas sampling bag is connected to a gas purifier via a pipeline. One side of the top of the gas sampling device is connected to a hydraulic pump via a hydraulic pipeline. The beneficial effects are: the residual associated gas is introduced into the gas purifier for harmless treatment; furthermore, after gas sampling, the hydraulic pump returns the oil and gas mixture extracted from the wellhead to the wellhead pipeline, preventing crude oil wastewater from spilling onto the ground. This achieves harmless treatment of toxic and harmful gases such as hydrogen sulfide in the associated gas, reducing the release of toxic gases during sampling and preventing personal injury accidents.

[0008] The aforementioned utility model achieves closed-loop sampling and can mix the remaining oil and gas and hydraulically return it to the wellhead pipeline, demonstrating significant effectiveness. However, some gas remains inside the sampling container, which may lead to situations where gas is not expelled before sampling and testing, affecting the accuracy of the detection.

[0009] Patent application CN201821746746.7 discloses a hydrogen sulfide gas sampling device, which relates to a gas sampling tool for associated gas from crude oil in the petroleum industry. This device can be installed at wellheads or metering stations on various oil pipelines equipped with gate valves to obtain hydrogen sulfide gas samples from the pipelines and return excess gas and liquid to the pipelines. It avoids the shortcomings of the aforementioned gas sampling methods, simplifies the operating procedures, prevents hydrogen sulfide gas leakage, ensures the personal safety of operators, improves work efficiency, and reduces the labor intensity of workers.

[0010] However, the above-mentioned device has a small volume and is installed at the sampling valve. If the gas volume is small, there is a problem that the gas sample cannot be taken or the gas volume of the sample taken is insufficient, which cannot meet the sampling needs. Summary of the Invention

[0011] The purpose of this invention is to provide a closed-loop gas sampling device for oil pipelines. This device can be connected to the sampling gate at the wellhead, metering station, or other oil pipelines, simplifying the structure and making it easy to carry. It solves the problem of requiring pre-calculation of air removal in existing samplers, ensuring the accuracy of the gas samples. It also addresses the difficulties of gas extraction from oil wells with small gas volumes and the challenges of recovering and treating sampling waste liquid. The sampling process is completely closed, preventing gas and liquid leakage, eliminating environmental pollution, and reducing hazardous waste treatment costs.

[0012] The technical solution of this utility model is: a closed gas sampling device for oil pipelines, comprising a sampling tube and a storage tank, wherein: the storage tank contains a level controller and a sampling tube equipped with a level transmitter; the level controller is electrically connected to an audible and visual alarm; the level controller, level transmitter, and audible and visual alarm are all connected to a mobile power supply; the storage tank contains an overflow valve, a connecting pipe, and a return plug; the sampling tube has an upper end cap and a lower end cap on the outside of the storage tank; the inlet pipe equipped with an inlet valve and the gas sampling pipe equipped with a water inlet valve and a sampling valve are both connected to the upper end cap; the level transmitter is installed in the sampling tube through the upper end cap; the inlet pipe can be connected to the sampling valve in the oil pipeline; the gas sampling pipe can be connected to a colorimetric tube and a negative pressure sampler in sequence; the return pipe contains a return valve and a vent valve, one end of which is connected to the inlet pipe, and the other end is connected to the lower end cap and the connecting pipe equipped with a connecting pipe valve.

[0013] Preferably, the level transmitter is a straight rod level transmitter and has a digital display function.

[0014] Preferably, the level controller is a float magnetic switch level controller.

[0015] Preferably, the audible and visual alarm and the power bank are fixed on the upper cover.

[0016] Preferably, the outer end of the water inlet valve is threadedly connected to the water inlet funnel.

[0017] Preferably, a pressure gauge is installed in the inlet pipe outside the inlet valve.

[0018] Preferably, the capacity of the liquid storage cylinder is set between 10L and 12L, and the lower end of the liquid storage cylinder is welded with a support with three or more legs, and rollers are installed at the lower ends of two legs on one side of the support.

[0019] Preferably, the connecting pipe equipped with the connecting pipe valve is connected to the inner pipeline of the vent valve in the return pipe; the connection between the return pipe and the inlet pipe is located in the pipeline outside the pressure gauge.

[0020] Preferably, the connecting pipe is located at the bottom of the liquid storage cylinder; the reinjection plug and the overflow valve are both located at the top of the liquid storage cylinder. The reinjection plug connected in the liquid storage cylinder consists of a threaded plug and a plug body. The plug body has internal threads and can be threadedly connected to the threaded plug or the connector of the high-pressure air pump.

[0021] Preferably, the liquid inlet pipe is connected to the sampling valve in the oil pipeline via a hose and a quick connector, and the gas sampling pipe is connected in sequence to the colorimetric tube and the negative pressure sampler via a hose.

[0022] Before sampling, this invention fills the sampling tube and inlet pipe with water and removes air to avoid pre-emptive gas replacement during sampling and ensure sampling accuracy. The liquid level transmitter in this device displays the gas volume, accurately determining its magnitude. The liquid in the sampling tube enters the storage tank via a connecting pipe to increase the liquid volume. A liquid level controller is installed in the storage tank, which, when connected to an audible and visual alarm, provides a liquid level alarm function, ensuring that the collected liquid sample meets the requirements for the gas sample. After sampling, an air pump is used to reinject the waste liquid and gas into the oil production process through the return pipe, avoiding waste liquid treatment.

[0023] The liquid storage cylinder of this invention has a volume between 10L and 12L, which can meet the requirements for gas sampling capacity and solve the problems of small capacity and difficulty in gas sampling of current hydrogen sulfide sampling devices.

[0024] This device is completely sealed and leak-free during the sampling process, achieving zero pollution and eliminating test errors caused by the estimated discharge of unclean air, thus ensuring accurate sampling. The liquid level is displayed by a liquid level transmitter, which can accurately determine the amount of gas. After the liquid level controller is installed in the liquid storage tank and connected to the audible and visual alarm, it has a liquid level alarm function to ensure that the liquid volume is sufficient to meet the gas sampling requirements.

[0025] Using this device for sampling is not only environmentally friendly but also meets the requirements for safe operation, ensuring the personal safety of operators and effectively reducing the labor intensity of workers. It has significant effects and application value. Attached Figure Description

[0026] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the structure of this utility model.

[0027] In the picture: 1. Inlet pipe; 2. Pressure gauge; 3. Inlet valve; 4. Audible and visual alarm; 5. Level transmitter; 6. Top cover; 7. Water funnel; 8. Water valve; 9. Sampling valve; 10. Gas intake pipe; 11. Overflow valve; 12. Sampling pipe; 13. Level controller; 14. Storage tank; 15. Connecting pipe; 16. Connecting pipe valve; 17. Vent valve; 18. Bottom cover; 19. Roller; 20. Return pipe valve; 21. Return pipe; 22. Return plug; 23. Support; 24. Power supply. Detailed Implementation

[0028] The accompanying drawings are for reference and illustration only and are not intended to limit the scope of protection of this utility model. The technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0029] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0030] In the description of this utility model, it should be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, in the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0031] See Figure 1 A closed-loop gas sampling device for an oil pipeline is provided, comprising a sampling tube 12 and a storage tank 14. The storage tank 14 contains a level controller 13 and a sampling tube 12 equipped with a level transmitter 5. The level controller 13 is electrically connected to an audible and visual alarm 4. The level controller 13, the level transmitter 5, and the audible and visual alarm 4 are all connected to a mobile power supply 24. The storage tank 14 contains an overflow valve 11, a connecting pipe 15, and a backfill plug 22. The two ends of the sampling tube 12 are provided with an upper end cap 6 and a lower end cap 18 on the outside of the storage tank 14. The inlet pipe 1, equipped with the inlet valve 3, and the gas inlet pipe 10, equipped with the water inlet valve 8 and the sampling valve 9, are both connected to the upper end cover 6. The level transmitter 5 is installed in the sampling pipe 12 through the upper end cover 6. The inlet pipe 1 can be connected to the sampling valve in the oil pipeline, and the gas inlet pipe 10 can be connected to the colorimetric tube and the negative pressure sampler in sequence. The return pipe 21 is equipped with the return valve 20 and the vent valve 17, and one end is connected to the inlet pipe 1, and the other end is connected to the lower end cover 18 and the connecting pipe 15 equipped with the connecting pipe valve 16.

[0032] To achieve closed-loop sampling and prevent gas-liquid leakage, thus eliminating environmental pollution and reducing hazardous waste treatment costs, this invention includes an overflow valve 11, a connecting pipe 15, and a return plug 22 within the storage cylinder 14. The connecting pipe 15 is connected to a return pipe 21 equipped with a return valve 20 and a vent valve 17 via a connecting pipe valve 16. The return section, consisting of the return valve 20, return pipe 21, and return plug 22, discharges the tested liquid sample from the storage cylinder 14 into the oil pipeline. Alternatively, during sampling, if the liquid level in the storage cylinder 14 becomes too high, sampling is stopped, and excess oil is discharged into the oil pipeline by switching different control valves. The liquid level in the storage cylinder 14 can be detected by an audible and visual alarm 4. The audible and visual alarm 4, level transmitter 5, level controller 13, and mobile power supply 24 can all be purchased commercially.

[0033] After sampling is completed, the connecting pipe valve 16, vent valve 17, and inlet valve 3 are closed. Air is injected through the backfill plug 22 to push the remaining gas and liquid in the storage cylinder 14 and the sampling pipe 12, which is connected to the return pipe 21 through the lower end cap 18 of the sampling pipe, back into the oil pipeline. This achieves closed sampling, prevents gas and liquid leakage, and solves the waste liquid treatment problem.

[0034] To address the issue of small volume in existing samplers, this invention incorporates a liquid storage tank 14, within which a level transmitter 5 is installed in the sampling tube 12. A level controller 13, also installed in the storage tank 14, is electrically connected to an audible and visual alarm 4. When the liquid level in the storage tank 14 reaches the target level, the alarm 4 sounds. The level transmitter 5 displays the liquid level, and once the target level is reached, the operator can stop the liquid intake and manually calculate the amount of gas to be sampled. By using the storage tank 14, the small volume problem of existing samplers is solved, while also simplifying use and operation.

[0035] To address the issue of pre-calculation of air displacement in existing samplers and ensure the accuracy of gas samples, this invention installs not only a sampling valve 9 but also a water inlet valve 8 in the gas sampling pipe 10 connected to the upper end cap 6 of the sampling tube; simultaneously, an inlet valve 3 is installed in the liquid inlet pipe 1 connected to the upper end cap 6 of the sampling tube. The liquid inlet valve 3, water inlet valve 8, and sampling valve 9 are opened, while all other valves are closed. Water is added through water inlet valve 8 until the liquid inlet pipe 1 and sampling pipe 12 are full. Then, the water inlet valve 8 and sampling valve 9 are closed.

[0036] This utility model can be connected to the sampling gate at the wellhead of an oil well, a metering station, or other oil pipelines. It has a simple structure, is easy to transport, has low manufacturing and processing costs, and has significant application effects.

[0037] Based on the above embodiment one, the present invention also has the following embodiments: In a preferred embodiment, the level transmitter 5 is a straight rod level transmitter with digital display functionality.

[0038] In a preferred embodiment, the level controller 13 is a float magnetic switch level controller.

[0039] In a preferred embodiment, the audible and visual alarm 4 and the power bank are fixed on the upper cover 6.

[0040] In a preferred embodiment, the outer end of the water valve 8 is threadedly connected to the water funnel 7, and water is added to the device through the water funnel 7 to replace the air inside, which is more convenient.

[0041] In a preferred embodiment, a pressure gauge 2 is installed in the inlet pipe 1 outside the inlet valve 3, and the pressure change inside the device can be easily observed through the pressure gauge 2.

[0042] In a preferred embodiment, the capacity of the liquid storage cylinder 14 is set between 10L and 12L, which can fully meet the needs of oil wells with high water content and low gas volume; the lower end of the liquid storage cylinder 14 is welded with a support 23 with more than three legs, and rollers 19 are installed at the lower ends of two legs on one side of the support 23 to facilitate pulling the device on the ground.

[0043] In a preferred embodiment: the connecting pipe 15, which is equipped with the connecting pipe valve 16, is connected to the inner pipeline of the vent valve 17 in the return pipe 21; the connection between the return pipe 21 and the inlet pipe 1 is located in the pipeline outside the pressure gauge 2.

[0044] In a preferred embodiment: the connecting pipe 15 is located at the bottom of the liquid storage cylinder 14; the reinjection plug 22 and the overflow valve 11 are both located at the top of the liquid storage cylinder 14. The reinjection plug 22 connected in the liquid storage cylinder 14 consists of a threaded plug and a plug body. The plug body has internal threads and can be threadedly connected to the threaded plug or the connector thread of a high-pressure air pump. When pumping air into the liquid storage cylinder 14 through the reinjection plug 22, the threaded plug in the reinjection plug 22 is first removed, and then the plug body is threadedly connected to the connector thread of the high-pressure air pump. After reinjection is completed, the threaded plug and the plug body are connected and a seal is maintained between them.

[0045] In a preferred embodiment: the liquid inlet pipe 1 is connected to the sampling valve in the oil pipeline via a hose and a quick connector, and the gas sampling pipe 10 is connected in sequence to the colorimetric tube and the negative pressure sampler via a hose.

[0046] This invention allows for sampling at the wellhead of an oil well, at a metering station, or at sampling gates in other oil pipelines. The device is placed on the ground near the sampling valve in the oil pipeline to be sampled, such as the wellhead sampling valve in an oil well, the sampling valve in a gathering and transportation station, or other sampling valves in oil pipelines. The following example, taking a gas sample from an oil wellhead, illustrates the method of using this device: Open the water inlet valve 8, the liquid inlet valve 3, and the sampling valve 9; keep the other valves closed.

[0047] Water is added through the water funnel 7 until the inlet pipe 1 and the sampling pipe 12 are full of water. Then, the water addition is stopped and the water addition valve 8 and the sampling valve 9 are closed.

[0048] Turn on the power bank, press the switch of the audible and visual alarm 4, and start the level transmitter 5 and level controller 13.

[0049] Open the overflow valve 11 and connect the inlet pipe 1 in this device to the wellhead sampling gate through a hose and a quick connector; open the wellhead sampling valve and the inlet valve 3, and use the inlet valve 3 and the connecting pipe valve 16 to control the flow rate. The opening degree of the connecting pipe valve 16 is 1 / 2 of that of the inlet valve 3.

[0050] The liquid level in the sampling tube 12 is observed by the liquid level transmitter 5. When the required or set liquid level is reached, the liquid inlet valve 3 is closed to stop the liquid inlet. The amount of gas is calculated manually based on the amount of liquid in the sampling tube 12.

[0051] When the well fluid has a high water content and a low gas volume, and the volume of the storage tank 14 cannot meet the gas extraction requirements, the red indicator light in the audible and visual alarm 4 will light up and emit a buzzer sound, indicating that the storage tank 14 will be full. A sludge tank will be placed at the overflow port of the overflow valve 11 to collect the sludge until the gas volume in the sampling tube 12 reaches the required level.

[0052] Slightly open sampling valve 9 to purge residual gas from sampling tube 12, then close sampling valve 9. The testing personnel select a colorimetric tube based on the color of the hydrogen sulfide content marker at the wellhead and cut off the tube's plug. Following the direction of the arrow on the colorimetric tube, connect one end of the tube to the flexible hose outside the gas inlet 10 and the other end to the negative pressure sampler, then open sampling valve 9.

[0053] When taking gas samples, follow the standard procedures for taking gas samples and record the sampled values.

[0054] Waste liquid reinjection: Connect the high-pressure air pump to the reinjection plug 22, open the return valve 20, close the overflow valve 11 and the vent valve 17, inject air, and return the waste liquid in the sampling tube 12 and the storage tank 14 back to the wellhead flow.

[0055] Since the connecting pipe 15 and the connecting pipe valve 16 are connected to the return pipe 21, when the pressure in the storage tank 14 is high, the waste liquid in the storage tank 14 enters the return pipe 21 through the connecting pipe 15, and the waste liquid in the sampling pipe 12 enters the return pipe 21 through the lower end cap 18 and the connecting pipe and is reinjected into the wellhead sampling valve through the inlet pipe 1.

[0056] When the level controller 13 alarms, stop the air pumping, disconnect the high-pressure air pump and the connected pipeline, and install the plug in the reinjection plug 22. Close the inlet valve 3, disconnect the connected hose and quick connector, retrieve the tools and equipment, clean off any oil stains, and complete the air sample collection operation.

[0057] The well fluid collected in the waste bin is collected by operators and sent to the wastewater recycling station for unified hazardous waste treatment.

[0058] The embodiments described above are merely typical examples, but the present invention is not limited to these embodiments. Those skilled in the art can make modifications without departing from the spirit and teachings of the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the inventive spirit and concept of the present invention should be included within the protection scope of the present invention. Therefore, the protection scope is not limited to the above description.

Claims

1. A closed-loop gas sampling device for oil pipelines, comprising a sampling tube and a liquid storage cylinder, characterized in that the liquid storage cylinder... The cylinder contains a level controller and a sampling tube with a level transmitter installed. The level controller is electrically connected to an audible and visual alarm. The level controller, level transmitter, and audible and visual alarm are all connected to a power source. The cylinder body contains an overflow valve, a connecting pipe, and a return plug. The sampling tube has an upper end cap and a lower end cap on the outside of the cylinder. The inlet pipe with an inlet valve and the air intake pipe with a water inlet valve and a sampling valve are both connected to the upper end cap. The level transmitter is installed in the sampling tube through the upper end cap. The inlet pipe can be connected to the sampling valve in the oil pipeline, and the air intake pipe can be connected to the colorimetric tube and the negative pressure sampler in sequence. The return pipe contains a return valve and a vent valve, and one end is connected to the inlet pipe, and the other end is connected to the lower end cap and the connecting pipe with a connecting pipe valve.

2. The closed-loop gas sampling device for oil pipelines as described in claim 1, characterized in that, The level transmitter is a straight rod level transmitter with digital display function.

3. The closed-loop gas sampling device for oil pipelines as described in claim 1, characterized in that, The liquid level controller is a float magnetic switch liquid level controller.

4. The closed-loop gas sampling device for oil pipelines as described in claim 1, characterized in that, The audible and visual alarm and the power bank are fixed on the top cover.

5. The closed-loop gas sampling device for oil pipelines as described in claim 1, characterized in that, The outer end of the water filling valve is threadedly connected to the water filling funnel.

6. The closed-loop gas sampling device for oil pipelines as described in claim 1, characterized in that, A pressure gauge is installed in the inlet pipe outside the inlet valve.

7. The closed-loop gas sampling device for oil pipelines as described in claim 1, characterized in that, The capacity of the liquid storage cylinder is set between 10L and 12L. The lower end of the liquid storage cylinder is welded with a support with three or more legs, and rollers are installed at the lower ends of two legs on one side of the support.

8. The closed-loop gas sampling device for oil pipelines as described in claim 1, characterized in that, The connecting pipe equipped with the connecting pipe valve is connected to the inner pipeline of the vent valve in the return pipe; the connection between the return pipe and the inlet pipe is located in the pipeline outside the pressure gauge.

9. A closed-loop gas sampling device for oil pipelines as described in claim 8, characterized in that, The connecting pipe is located at the bottom of the liquid storage cylinder; the reinjection plug and the overflow valve are both located at the top of the liquid storage cylinder. The reinjection plug connected in the liquid storage cylinder consists of a threaded plug and a plug body. The plug body has internal threads and can be threadedly connected to the threaded plug or the connector of the high-pressure air pump.

10. A closed-loop gas sampling device for oil pipelines as described in claim 1, characterized in that, The liquid inlet pipe is connected to the sampling valve in the oil pipeline via a hose and a quick connector, and the gas sampling pipe is connected to the colorimetric tube and the negative pressure sampler in sequence via a hose.

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