Methane leakage detection alarm suitable for oil and gas field production device area

Abstract

The invention belongs to the technical field of oil and gas field production devices, and particularly relates to a methane leakage detection alarm suitable for an oil and gas field production device area. Comprising a shell, and a methane sensor, a computer, an alarm, a circuit board, a metering valve and an air pump are arranged in the shell; the methane sensor is connected with the air pump, and the air pump is connected with a telescopic rod through a sampling pipe; the telescopic rod is arranged outside the shell; the telescopic rod goes deep into the part for detection; the methane sensor is connected with the computer, the computer is connected with the circuit board, and the circuit board is connected with the alarm.

Description

Technical Field

[0001] The present invention belongs to the technical field of oil and gas field production devices, and particularly relates to a methane leakage detection and alarm instrument applicable to the oil and gas field production device area. Background Art

[0002] Methane is the main component of natural gas and coal gas, and is also an intermediate product in oil and petrochemical production. It widely exists in industries such as natural gas coal production, coal chemical industry, oil and natural gas extraction, and petrochemical industry. At the same time, it is widely used as a fuel in civil and industrial applications. The industrialization process of liquefied natural gas has brought economy and convenience to mankind. However, during the processes of natural gas extraction, transportation, storage, and use, leakage often occurs and is not detected in time, leading to major accidents such as fires and explosions. In addition, methane is colorless and odorless, and it is also an important greenhouse gas. Every year, a large amount of methane leaks from natural gas fields into the atmosphere, further exacerbating the global greenhouse effect.

[0003] Oil and gas field production stations are the systems with the largest methane leakage volume. In oil and gas field production stations, there are natural gas wellheads, natural gas gathering stations, natural gas booster stations, natural gas pigging stations, and natural gas purification plants. Methane leakage exists in each different type of natural gas production station. At the same time, in each process of the natural gas production process, there are many components such as valves, joints, flanges, valve cores, blind plates, pressure gauges, metering devices, and greasing holes that are prone to methane leakage. These components are the areas most prone to methane leakage, but current equipment is not suitable for flexibly and highly precisely detecting the methane concentration in the above areas. The main problems are that existing high-precision methane detectors are too large in weight and mass to penetrate into each component unit for detection. In addition, the detection accuracy of existing portable methane detectors is not high enough to accurately collect low-concentration methane, resulting in the inability to scientifically evaluate the amount of methane leaked from oil and gas field production stations.

[0004] In view of this, the present invention is specifically proposed. Summary of the Invention

[0005] In order to solve the technical problems existing in the prior art, the present invention provides a methane leakage detection and alarm instrument applicable to the oil and gas field production device area. The telescopic rod provided by the present invention can penetrate into components for detection, improving the detection accuracy.

[0006] The present invention includes the following technical solutions:

[0007] The present invention provides a methane leakage detection and alarm instrument applicable to the oil and gas field production device area, including a housing, and a methane sensor, a computer, an alarm, a circuit board, a metering valve, and an air pump are arranged inside the housing;

[0008] The methane sensor is connected to the air pump, and the air pump is connected to a telescopic rod through a sampling tube;

[0009] The telescopic rod is arranged outside the housing; the telescopic rod is extended into the components for detection;

[0010] The methane sensor is connected to the computer, the computer is connected to the circuit board, and the circuit board is connected to the alarm.

[0011] Further, the methane sensor includes an optical detection unit and a signal acquisition module. The optical detection unit is connected to the signal acquisition module, and the signal acquisition module is connected to the computer.

[0012] Further, the optical detection unit includes an air chamber. A reflector is arranged in the air chamber. A methane detection mechanism, a water vapor detection mechanism, and a carbon dioxide detection mechanism are arranged at the outlet end of the air chamber. An infrared emitter is arranged at the inlet end of the air chamber.

[0013] Further, the methane detection mechanism includes a first-band detector and a first-band filter; the water vapor detection mechanism includes a second-band detector and a second-band filter; the carbon dioxide detection mechanism includes a third-band detector and a third-band filter;

[0014] The bands emitted by the infrared emitter include the first band detected by the first-band detector, the second band detected by the second-band detector, and the third band detected by the third-band detector;

[0015] Wherein: the wavelength of the first band > the wavelength of the second band > the wavelength of the third band.

[0016] Further, a particulate filter is arranged outside the air chamber at the inlet end of the air chamber.

[0017] Further, the signal acquisition module includes a signal converter and an oscilloscope; the methane detection mechanism is respectively connected to the signal converter and the oscilloscope, and both the signal converter and the oscilloscope are connected to the computer.

[0018] Further, the alarm also includes a humidity sensor and a temperature sensor. The humidity sensor is used to detect the ambient humidity during on-site detection and send it to the computer. The temperature sensor is used to detect the ambient temperature during on-site detection and send it to the computer; the computer includes a calibration unit, and the calibration unit includes a calibration formula. The calibration formula is:

[0019] C 校 = C0 - CRH(CRH = 0.2778×RH2 - 0.2094×RH + 0.5295) - CT

[0020] (CT = 0.1745XT2 - 0.1284XT + 0.2238);

[0021] Where: C 校 : The calibrated methane concentration, C 0 : The methane concentration detected by the methane sensor, C RH : The variable of methane concentration caused by humidity influence, C T : The variable of methane concentration caused by temperature influence, X RH : The ambient humidity during on-site detection, X T : The ambient temperature during on-site detection.

[0022] Further, the alarm also includes a display screen, and the display screen is connected to the computer.

[0023] Further, the alarm also includes a lithium battery, and the lithium battery powers the methane sensor, computer, alarm, circuit board and air pump.

[0024] Further, the alarm also includes a flying mouse remote control keyboard.

[0025] Adopting the above technical solutions, the present invention has the following advantages:

[0026] 1. The telescopic rod provided by the present invention can penetrate into the components for detection, improving the detection accuracy.

[0027] 2. The present invention combines three band absorption spectrum sensors together, which can detect carbon dioxide, water vapor and methane simultaneously. Because the detection of methane requires precise sensing to compensate for the cross-sensitivity between water vapor and methane, allowing drift compensation and eliminating potential offsets in methane measurement. At the same time, different greenhouse gases have different absorption rates for different infrared bands, resulting in different signal intensities reaching the detector. Compared with the existing NDIR technology, this technology realizes the simultaneous detection of three greenhouse gases, carbon dioxide, water vapor and methane, and avoids the cross-sensitivity interference between different greenhouse gases by establishing a calibration model, further improving the accuracy of methane detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0029] Figure 1Schematic diagram of a methane leakage detection and alarm device applicable to an oil and gas field production device area in an embodiment of the present invention;

[0030] Figure 2 Schematic diagram of a methane sensor in an embodiment of the present invention;

[0031] Figure 3 Schematic diagram of an optical detection unit in an embodiment of the present invention;

[0032] In the figure: 1 - housing, 2 - methane sensor, 21 - optical detection unit, 211 - gas chamber, 212 - mirror, 213 - first - band detector, 214 - first - band filter, 215 - second - band detector, 216 - second - band filter, 217 - third - band detector, 218 - third - band filter, 219 - infrared emitter, 22 - signal acquisition module, 221 - signal converter, 222 - oscilloscope, 23 - particulate filter, 3 - sampling tube, 4 - telescopic rod, 5 - computer, 6 - alarm, 7 - circuit board, 8 - metering valve, 9 - air pump, 10 - display screen, 11 - lithium battery, 12 - air mouse remote control keyboard. Detailed implementation manners

[0033] The following description provides many different embodiments or examples for implementing different features of the present invention. The elements and arrangements described in the following specific examples are only used to concisely express the present invention, and they are only examples and not intended to limit the present invention.

[0034] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a connection that can communicate with each other; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be the communication inside multiple elements or the interaction relationship between multiple elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0036] This embodiment provides a methane leakage detection and alarm device applicable to an oil and gas field production device area, as Figure 1As shown in the figure, it includes a housing 1, and a methane sensor 2, a computer 5, an alarm 6, a circuit board 7, a metering valve 8 and an air pump 9 are arranged inside the housing 1;

[0037] The methane sensor 2 is connected to the air pump 9, and the air pump 9 is connected to a telescopic rod 4 through a sampling tube 3;

[0038] The telescopic rod 4 is arranged outside the housing 1; the telescopic rod 4 is used to penetrate into components for detection;

[0039] The methane sensor 2 is connected to the computer 5, the computer 5 is connected to the circuit board 7, and the circuit board 7 is connected to the alarm 6.

[0040] It should be noted that the structures of the telescopic rods 4 in the prior art are all applicable to the present invention, but it is necessary to ensure that the inside of the telescopic rod 4 is through so that gas can pass through.

[0041] In some embodiments, the metering valve 8 is arranged between the methane sensor 2 and the telescopic rod 4, and the metering valve 8 is connected to the computer 5. The methane emission can be obtained through the metering valve 8.

[0042] In some embodiments, as Figure 2 shown, the methane sensor 2 includes an optical detection unit 21 and a signal acquisition module 22, the optical detection unit 21 is connected to the signal acquisition module 22, and the signal acquisition module 22 is connected to the computer 5.

[0043] In some embodiments, as Figure 3 shown, the optical detection unit 21 includes an air chamber 211, a mirror 212 is arranged inside the air chamber 211, a methane detection mechanism, a water vapor detection mechanism and a carbon dioxide detection mechanism are arranged at the outlet end of the air chamber 211, and an infrared emitter 219 is arranged at the inlet end of the air chamber 211.

[0044] In some embodiments, the methane detection mechanism includes a first band detector 213 and a first band filter 214; the water vapor detection mechanism includes a second band detector 215 and a second band filter 216; the second carbon dioxide detection mechanism includes a third band detector 217 and a third band filter 218;

[0045] The bands emitted by the infrared emitter 219 include the first band detected by the first band detector 213, the second band detected by the second band detector 215 and the third band detected by the third band detector 217;

[0046] Wherein: the wavelength of the first band > the wavelength of the second band > the wavelength of the third band.

[0047] When infrared light irradiates methane molecules, the infrared light that matches the resonance frequency of methane molecules will be absorbed, causing the methane molecules to transfer to the excited state, while the infrared light with non-resonant frequencies will be reflected or transmitted by the methane molecules. The intensity of light at a specific wavelength will change corresponding to the concentration of methane gas, and its change law conforms to Lambert-Beer's law of absorption. Therefore, the concentration of methane gas can be calculated based on the change in the intensity of the absorbed light.

[0048] The process of the optical detection unit 21 for realizing methane gas is as follows: Infrared light is emitted by the infrared emitter 219 and propagates between the reflectors 212. After multiple reflections, the infrared light reaches the short-path third-band detector 217. The infrared light in the third band is transmitted to the third-band detector 217 through the third-band detector 217. The remaining infrared light is reflected and further propagates between the reflectors 212. The infrared light reaches the second-band filter 216. The second-band filter 216 transmits the infrared light in the second band to the second-band detector 215. The remaining infrared light is further propagated between the reflectors 212. The infrared light reaches the first-band filter 214. The first-band filter 214 transmits the infrared light in the first band to the first-band detector 213.

[0049] In some embodiments, a particulate filter 23 is provided outside the gas chamber 211 at the inlet end of the gas chamber 211.

[0050] In some embodiments, the signal acquisition module 22 includes a signal converter 221 and an oscilloscope 222; the methane detection mechanism is respectively connected to the signal converter 221 and the oscilloscope 222, and both the signal converter 221 and the oscilloscope 222 are connected to the computer 5.

[0051] The methane standard gas diluted by the dynamic dilutor is introduced into the temperature and humidity control box to regulate the temperature and humidity of the methane standard gas, and finally introduced into the methane detector for detection, thereby establishing a calibration formula. During on-site detection, the temperature and humidity sensor detects the temperature and humidity in the environment in real time, and corrects the methane concentration through the pre-set calibration formula and displays the correct methane concentration value.

[0052] In some embodiments, the alarm also includes a humidity sensor and a temperature sensor. The humidity sensor is used to detect the environmental humidity during on-site detection and send it to the computer 5, and the temperature sensor is used to detect the environmental temperature during on-site detection and send it to the computer 5; the computer 5 includes a calibration unit, and the calibration unit includes a calibration formula. The calibration formula is: C 校 =C 0 -C RH (C RH =0.2778X RH 2 -0.2094XRH +0.5295)-C T

[0053] (C T = 0.1745X T 2 -0.1284X T +0.2238);

[0054] Where: C 校 : The calibrated methane concentration, C 0 : The methane concentration detected by the methane sensor, C RH : The variable of the methane concentration caused by the influence of humidity, C T : The variable of the methane concentration caused by the influence of temperature, X RH : The ambient humidity during on-site detection, X T : The ambient temperature during on-site detection.

[0055] In some embodiments, the alarm further includes a display screen 10, and the display screen 10 is connected to the computer 5.

[0056] In some embodiments, the alarm further includes a lithium battery 11, and the lithium battery 11 supplies power to the methane sensor 2, the computer 5, the alarm 6, the circuit board 7 and the air pump 9.

[0057] In some embodiments, the alarm further includes a flying mouse remote control keyboard 12.

[0058] In some embodiments, the computer 5 is connected to a relay, and a gas outlet, a power display and a start switch are arranged on the housing 1.

[0059] During use, first press the start switch to trigger the start of the lithium battery 11. The lithium battery 11 starts the relay, the air pump 9, the methane sensor 2, the alarm 6, the power display, the temperature sensor, the humidity sensor, the computer 5 and the display screen 10. Use the flying mouse remote control keyboard 12 to open the methane detection software on the computer 5 and set the corresponding methane concentration alarm limit. The operator holds the telescopic rod 4 to detect the methane concentration in different production device areas. When the length of the telescopic rod 4 is not enough, adjust the length of the telescopic rod 4 accordingly. The methane concentration signal detected by the methane sensor 2 is transmitted to the oscilloscope 222 and the signal converter 221 by the signal converter 221, and is transmitted to the computer 5 through the signal converter. The temperature sensor and the humidity sensor detect the temperature and humidity of the sampling environment in real time and transmit them to the computer 5. The computer 5 performs temperature and humidity compensation calibration on the methane concentration according to the detected temperature and humidity, compares the calibrated methane concentration with the set methane concentration alarm limit. When it is greater than the methane concentration alarm limit, the alarm signal is transmitted to the circuit board 7, and the circuit board 7 controls the alarm 6 to give an alarm.

[0060] Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A methane leak detection alarm suitable for oil and gas field production equipment area, characterized in that: It comprises a housing (1), wherein a methane sensor (2), a computer (5), an alarm (6), a circuit board (7), a metering valve (8) and an air pump (9) are arranged in the housing (1); The methane sensor (2) is connected to the air pump (9), and the air pump (9) is connected to a telescopic rod (4) via a sampling tube (3); The telescopic rod (4) is arranged outside the housing (1); the telescopic rod (4) is used to penetrate into the component for inspection; The methane sensor (2) is connected to the computer (5), the computer (5) is connected to the circuit board (7), and the circuit board (7) is connected to the alarm (6).

2. A methane leak detection alarm device suitable for oil and gas field production equipment area as claimed in claim 1, characterized in that: The methane sensor (2) comprises an optical detection unit (21) and a signal acquisition module (22), wherein the optical detection unit (21) is connected to the signal acquisition module (22), and the signal acquisition module (22) is connected to the computer (5).

3. A methane leak detection alarm device suitable for oil and gas field production equipment area as claimed in claim 2, characterized in that: The optical detection unit (21) comprises an air chamber (211), a reflector (212) is arranged in the air chamber (211), a methane detection mechanism, a water vapor detection mechanism and a carbon dioxide detection mechanism are arranged at the outlet end of the air chamber (211), and an infrared emitter (219) is arranged at the inlet end of the air chamber (211).

4. A methane leak detection alarm device suitable for oil and gas field production equipment area as claimed in claim 3, characterized in that: The methane detection mechanism comprises a first-band detector (213) and a first-band filter (214); the water vapor detection mechanism comprises a second-band detector (215) and a second-band filter (216); and the carbon dioxide detection mechanism comprises a third-band detector (217) and a third-band filter (218); The wavebands emitted by the infrared emitter (219) include a first waveband detected by the first waveband detector (213), a second waveband detected by the second waveband detector (215), and a third waveband detected by the third waveband detector (217); Among them: the wavelength of the first band>the wavelength of the second band>the wavelength of the third band.

5. A methane leak detection alarm device suitable for oil and gas field production equipment area as claimed in claim 4, characterized in that: A particle filter (23) is provided outside the air chamber (211) at the inlet end of the air chamber (211).

6. A methane leak detection alarm device suitable for oil and gas field production equipment area as claimed in claim 3, characterized in that: The signal acquisition module (22) comprises a signal converter (221) and an oscilloscope (222); the methane detection mechanism is connected to the signal converter (221) and the oscilloscope (222) respectively, and the signal converter (221) and the oscilloscope (222) are both connected to a computer (5).

7. A methane leak detection alarm device suitable for oil and gas field production equipment area as claimed in claim 1, characterized in that: The alarm device further comprises a humidity sensor and a temperature sensor, wherein the humidity sensor is used to detect the ambient humidity during on-site detection and send the result to the computer (5), and the temperature sensor is used to detect the ambient temperature during on-site detection and send the result to the computer (5); the computer (5) comprises a calibration unit, and the calibration unit comprises a calibration formula, wherein the calibration formula is: C 校 =C0-C RH (C RH =0.2778X RH 2 -0.2094X RH +0.5295)-C T (C T =0.1745X T 2 -0.1284X T +0.2238); Where: C 校 : Calibrated methane concentration, C0: Methane concentration detected by methane sensor (2), C RH : The variation of methane concentration due to humidity, C T : The variation of methane concentration due to temperature, X RH : Ambient humidity during on-site testing, X T : Ambient temperature during on-site testing.

8. A methane leak detection alarm device suitable for oil and gas field production equipment area as claimed in claim 1, characterized in that: The alarm device also includes a display screen (10), and the display screen (10) is connected to the computer (5).

9. A methane leak detection alarm device suitable for oil and gas field production equipment area as claimed in claim 1, characterized in that: The alarm device further comprises a lithium battery (11), and the lithium battery (11) supplies power to the methane sensor (2), the computer (5), the alarm (6), the circuit board (7) and the air pump (9).

10. A methane leak detection alarm device suitable for oil and gas field production equipment area as claimed in claim 1, characterized in that: The alarm device also includes a flying mouse remote control keyboard (12).

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