A device for detecting methane leakage from a submarine pipeline based on SPR technology

Abstract

This invention discloses a subsea pipeline methane leak detection device based on SPR technology, comprising: a gas sampling module for collecting seawater containing methane gas leaking from the subsea pipeline; a methane separation module for separating the methane gas from the seawater collected by the gas sampling module; a gas mixing module for mixing the methane gas separated by the methane separation module with nitrogen; and an SPR detection module for detecting the presence of methane gas in the gas mixing module based on the SPR effect. The detection system provided by this application is expected to enable real-time sampling and detection of subsea pipeline methane leaks using an ROV; the intensity-modulated near-infrared SPR detection device provided achieves a balance between miniaturization and high sensitivity compared to existing technologies.

Description

Technical Field

[0001] This invention belongs to the field of surface plasmon resonance (SPR) sensing, and in particular relates to a methane leakage device for subsea pipelines based on SPR technology. Background Technology

[0002] Leaks in subsea oil and gas pipelines are difficult to repair, causing not only economic and property losses but also pollution of the marine environment and even maritime explosions. Therefore, rapid underwater detection and location of minor leaks in subsea energy pipelines is of great significance. Developing real-time monitoring of minor leaks in subsea oil and gas production systems holds promise for early warning and location of small leaks, providing information support for preventative maintenance and emergency response in subsea production systems. Methane is a primary gas transported in subsea pipelines. The development of miniaturized sensors with high selectivity and sensitivity for trace amounts of methane, coupled with ROV (Remotely Operated Vehicle) capabilities for real-time methane detection, is an effective means of timely identifying subsea pipeline leaks.

[0003] SPR (Sequencing Precipitation Gas) sensing technology is a novel photoelectric detection technology. Compared with traditional gas sensors, it boasts advantages such as high sensitivity, real-time response, and resistance to electromagnetic interference. It has been widely applied in many important fields and is gradually maturing, showing promising development prospects. However, while current commercially available SPR detection instruments offer high accuracy, their complex structure and large size make them unsuitable for real-time detection via ROVs, significantly limiting their application in underwater pipeline leak detection. To integrate with an ROV, the sensing system must be miniaturized and integrated. However, current miniaturized SPR sensors on the market come at the cost of reduced sensitivity and detection limits, failing to achieve sensitive detection of trace gases. Therefore, designing a highly sensitive and miniaturized SPR methane sensing system that can be integrated with an ROV for real-time acquisition and detection presents a promising application prospect. Summary of the Invention

[0004] To solve the above problems, the technical solution adopted by the present invention is: a methane leakage device for subsea pipelines based on SPR technology, characterized in that it includes:

[0005] The gas collection module is used to collect seawater containing methane gas leaked from an undersea pipeline.

[0006] The methane separation module is used to separate the methane gas mixed in the seawater collected by the gas collection module.

[0007] A gas mixing module is used to mix the methane gas separated by the methane separation module with nitrogen gas;

[0008] The SPR detection module is used to detect the presence of methane gas in the gas mixing module based on the SPR effect.

[0009] Furthermore, the methane separation module includes a heating plate for heating the seawater collected by the gas collection module;

[0010] A gas-liquid separation membrane used to separate methane gas from seawater after the heating plate has been heated.

[0011] Furthermore: the gas mixing module includes a nitrogen storage chamber for storing nitrogen.

[0012] A flow meter that controls the proportion of nitrogen output from the nitrogen storage chamber mixes nitrogen and methane gas.

[0013] Furthermore: the SPR detection module includes,

[0014] A micro gas flow cell for circulating the gas mixed by the gas mixing module;

[0015] A sensitive membrane is disposed below the micro-gas flow cell;

[0016] A gold film is disposed beneath the sensitive membrane;

[0017] A K9 prism is disposed beneath the gold film;

[0018] A near-infrared laser is located below the K9 prism;

[0019] The near-infrared laser emits a laser beam through a first straight mirror to a K9 prism, which then illuminates the gold film and the sensitive film. The reflected light with the SPR effect is received by a second collimating mirror, which then transmits the light signal to an indium gallium arsenide photodetector for detection. The detected signal is then transmitted to the signal processing unit.

[0020] A method for detecting methane leaks in a subsea pipeline based on SPR technology, as described in any one of the above methods, includes the following steps:

[0021] S1: Based on the gas acquisition module, collect seawater containing methane gas leaked from the subsea pipeline;

[0022] S2: The seawater containing trace amounts of methane is heated by a heating plate, so that the trace methane gas in the seawater is separated from the seawater through a permeable liquid separation membrane, and the seawater is discharged through a wastewater outlet.

[0023] S3: The filtered methane gas enters the gas mixing module through a pipeline, where it mixes with the nitrogen gas released from the nitrogen storage chamber.

[0024] S4: The mixed gas enters the micro gas flow cell. The near-infrared laser emits a laser beam through the first collimating lens to the K9 prism, which then illuminates the gold film and the sensitive film. The reflected light with the SPR effect is received by the second collimating lens and then detected by the indium gallium arsenide photodetector for signal processing.

[0025] The laser is incident at a small angle to excite the near-infrared SPR effect. The reflected light carrying the SPR effect and the refractive index information of the test object is detected by the indium gallium arsenide photodetector after passing through the K9 prism, and the signal is transmitted to the signal processing unit, which processes the transmitted signal.

[0026] When the gas sample is free of methane, the SPR signal is stable. When methane is present in the gas, it binds to the sensitive membrane, causing a change in the membrane's refractive index, which in turn causes a change in the SPR signal. This change in signal is positively correlated with the methane concentration. Finally, the waste gas is discharged from the exhaust port.

[0027] The present invention provides a methane leakage device for subsea pipelines based on SPR technology. The present application has the following advantages: 1) The detection system provided by the present application has the special effect of miniaturization and has the potential to carry out real-time sampling and detection of methane leakage in subsea pipelines by ROV; 2) The intensity modulation near-infrared SPR detection device provided by the present application can achieve both miniaturization and high sensitivity compared with the existing technology. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a general schematic diagram of the detection device provided in this application.

[0030] Reference numerals: 1. Gas collection pipeline, 2. Water pump, 3. Transmission pipeline, 4. Nitrogen storage chamber, 5. Flow meter, 6. Gas-liquid separation membrane, 7. Wastewater outlet, 8. Heating plate, 9. SPR detection module, 10. Sensitive membrane, 11. First collimating lens, 12. Near-infrared laser, 13. Waste outlet, 14. Micro gas flow cell, 15. Gold membrane, 16. K9 prism, 17. Indium gallium arsenide photodetector, 18. Signal processing unit, 19. Second collimating lens. Detailed Implementation

[0031] It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0034] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0035] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms 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 on the scope of protection of this invention. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0036] For ease of description, spatial relative terms such as "above," "over," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation besides the orientation of the device as described in the figures. For example, if the device in the figures is inverted, a device described as "above" or "above" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0037] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0038] Figure 1 This is a general schematic diagram of the detection device provided in this application.

[0039] This application provides a subsea pipeline methane leakage device based on SPR technology, including a gas acquisition module, a methane separation module, a gas mixing module, and an SPR detection module.

[0040] The gas collection module is used to collect seawater containing methane gas leaked from a subsea pipeline.

[0041] The methane separation module is used to separate the methane gas mixed in the seawater collected by the gas collection module;

[0042] The gas mixing module is used to mix the methane gas separated by the methane separation module with nitrogen gas;

[0043] The SPR detection module is used to detect the presence of methane gas in the gas mixing module based on the SPR effect.

[0044] The gas collection module includes a gas collection pipe 1, a water pump 2, and a transmission pipe 3. The gas collection pipe 1 is used to collect methane gas discharged from the pipe leakage area and transport seawater containing trace amounts of methane gas to the water pump 2. The water pump 2 uses its thrust to transport the seawater and methane gas through the transmission pipe 3 to the methane separation and collection module.

[0045] The methane separation module includes a heating plate 8, a gas-liquid separation membrane 6, and a wastewater outlet 7. The heating plate 8 heats seawater containing trace amounts of methane, causing the trace methane in the seawater to pass through the gas-liquid separation membrane 6 and separate from the seawater. At the same time, the seawater is discharged through the wastewater outlet 7, and the filtered methane gas enters the gas mixing module through a pipeline.

[0046] The gas mixing module includes a nitrogen storage chamber 4 and a flow meter 5;

[0047] The methane gas entering the gas mixing module mixes with the nitrogen gas released from the nitrogen storage chamber 4. The nitrogen input ratio is controlled by the flow meter 5, so that the SPR detection module 9 has a continuous and stable trace amount of gas, ensuring the real-time monitoring performance of SPR, and thus detecting methane leakage at the first time.

[0048] The SPR detection module 9 includes...

[0049] Micro gas flow cell 14 for circulating the gas mixed by the gas mixing module;

[0050] A sensitive membrane 10 is disposed below the micro gas flow cell 14;

[0051] A gold film 15 is disposed below the sensitive membrane 10;

[0052] A K9 prism 16 is disposed below the gold film 15;

[0053] A near-infrared laser 12 is disposed below the K9 prism 16;

[0054] The near-infrared laser 12 emits laser light through the first collimating lens 11 to the K9 prism 16, which then irradiates the gold film 15 and the sensitive film 10. The reflected light with the SPR effect is received by the second collimating lens 19, which then transmits the light signal to the indium gallium arsenide photodetector 17 for detection. The detected signal is then transmitted to the signal processing unit 18.

[0055] Specifically, the gas entering the SPR detection module 9 passes through the micro gas flow cell 14, and the 1550nm laser 12 emits laser light through the first collimating lens 11 to the K9 prism 16, which then irradiates the gold film 15 and the sensitive film 10. The reflected light with the SPR effect is received by the first collimating lens 11 and then detected by the indium gallium arsenide photodetector 17 for signal processing.

[0056] When the gas sample is free of methane, the SPR signal is stable. When methane is present in the gas, it combines with the sensitive membrane 10, causing a change in the refractive index of the sensitive membrane 10, which in turn causes a change in the SPR signal. The signal change is positively correlated with the methane concentration. Finally, the waste gas is discharged from the waste outlet 13.

[0057] Specifically, the laser is incident at a small angle to excite the near-infrared SPR effect. The reflected light carrying the SPR effect and the refractive index information of the test object is detected by the indium gallium arsenide photodetector 17 after passing through the K9 prism 16, and the light signal is transmitted to the signal processing unit 18. The signal processing unit 18 is used to process the signal transmitted from the SPR detection module and transmit the processed signal to the ROV.

[0058] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0059] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, this specification should not be construed as a limitation of the present invention.

Claims

1. A device for detecting methane leaks from a subsea pipeline based on SPR technology, characterized in that: The device comprises: a gas collection module for collecting seawater mixed with methane gas leaked from the submarine pipeline; a methane separation module for separating the methane gas mixed in the seawater collected by the gas collection module; a gas mixing module for mixing the methane gas separated by the methane separation module with nitrogen gas; an SPR detection module for detecting whether there is methane gas in the gas mixing module based on the SPR effect; The gas mixing module comprises a nitrogen storage chamber for storing nitrogen gas, a flowmeter for controlling the output proportion of the nitrogen gas, and a mixing device for mixing the nitrogen gas and the methane gas. The SPR detection module comprises: a micro-gas flow cell for flowing the mixed gas in the gas mixing module; a sensitive membrane arranged below the micro-gas flow cell; a gold film arranged below the sensitive membrane; a K9 prism arranged below the gold film; a near-infrared laser arranged below the K9 prism; The near-infrared laser emits laser light to the K9 prism through a first collimating mirror, irradiates the gold film and the sensitive membrane, and the reflected light with the SPR effect is received by a second collimating mirror, then the light signal is transmitted to an indium gallium arsenide photodetector by the second collimating mirror for detection, and the detected signal is transmitted to the signal processing unit.

2. The device for detecting methane leakage from a submarine pipeline based on the SPR technology according to claim 1, wherein: The methane separation module comprises a heating plate for heating the seawater collected by the gas collection module; a gas-liquid separation membrane for separating the methane gas from the seawater heated by the heating plate.

3. The method of claim 1-2, wherein the method is a method of detecting a methane leak in a subsea pipeline using a device based on SPR technology, the method comprising: The device comprises the following steps: S1: collecting seawater mixed with methane gas leaked from the submarine pipeline based on the gas collection module; S2: heating the seawater with trace methane by the heating plate, so that the trace methane gas in the seawater is separated from the seawater through the gas-liquid separation membrane, and the seawater is discharged through the waste water outlet; S3: the filtered methane gas enters the gas mixing module through the pipeline, and the methane gas entering the gas mixing module is mixed with the nitrogen gas released from the nitrogen storage chamber; S4: the mixed gas enters the micro-gas flow cell, the near-infrared laser emits laser light to the K9 prism through the first collimating mirror, irradiates the gold film and the sensitive membrane, and the reflected light with the SPR effect is received by the second collimating mirror, so that the indium gallium arsenide photodetector detects and processes the signal; The laser is obliquely incident at a small angle to excite the near-infrared SPR effect, the reflected light with the SPR effect and the refractive index information of the measured substance is detected by the indium gallium arsenide photodetector after passing through the prism, and the signal is transmitted to the signal processing unit, and the signal processing unit is used for processing the transmitted signal; When there is no methane gas in the gas sample, the SPR signal is stable, when there is methane gas in the gas, the methane gas combines with the sensitive membrane, the refractive index of the sensitive membrane changes, thereby causing the SPR signal to change, the signal change is positively correlated with the methane concentration, finally, the waste gas is discharged from the waste outlet.

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