Device, system and method for real-time detection of carbon dioxide geological storage status

Abstract

The present invention belongs to the field of environmental monitoring, and specifically relates to a device, system and method for real-time detection of the geological storage state of CO2, which aims to solve the problem that the existing detection technology for the geological storage state of CO2 has high detection cost and cannot cope with the resistance spatial distribution and change of strongly heterogeneous geological bodies. The present invention includes: selecting a transmitting electrode and a receiving electrode, emitting a detection current of a preset waveform from the transmitting electrode, receiving the lost detection current through the receiving electrode, obtaining the potential difference between the electrodes, traversing all possible combinations of the transmitting electrode and the receiving electrode, obtaining a voltage data set of an azimuth, and then calculating the azimuth CO2 state, combining the azimuth CO2 states of all azimuths to obtain the overall distribution of the CO2 state, and combining the overall distribution of the CO2 states of all test wells to obtain the CO2 regional distribution. The present invention achieves large-scale real-time detection of the geological storage state of CO2 by depicting the resistivity difference of the geological body with high resolution.

Description

Background Art

[0002] In recent years, a large number of studies on the capture, utilization and storage of CO2 are being carried out around the world. A large amount of CO2 captured in industrial processes is injected into rock formations deep underground to permanently remove it from the atmosphere, thereby achieving the global goal of reducing atmospheric CO2 emissions. Injecting CO2 into underground reservoirs can not only increase the recovery rate, but also achieve the purpose of permanent storage of CO2. Although CO2 geological storage technology has matured, more and more evidence shows that the safety of CO2 geological storage is a technical bottleneck that restricts its large-scale promotion and application. How to effectively prevent, monitor and control CO2 leakage and ensure the safety of CO2 storage has become an important part of CO2 storage technology research and has received more and more attention.

[0003] One of the safety concerns of CO2 geological storage is the detection of CO2 plume movement and possible leakage. The current mainstream CO2 monitoring technologies include time-lapse seismic (also known as 4D seismic), repeated electromagnetic exploration (4D EM / CSEM), microseismic and GPS monitoring. Seismic has been identified as a high-cost, high-yield method, while 4D EM is considered a low-cost, high-yield CO2 monitoring technology. In fact, direct observation of the geological body where CO2 is stored can obtain more and more reliable data, but the cost of drilling a large number of detection wells is very high, and the problem of strong heterogeneity between wells in the geological body has not been well solved. Summary of the invention

[0004] In order to solve the above problems in the prior art, namely, the existing carbon dioxide geological storage state detection technology has a high detection cost, cannot cope with the problem of the spatial distribution and change of the resistance of the strongly heterogeneous geological body, and has a low detection accuracy in the vertical direction, the present invention provides a device for real-time detection of the geological storage state of carbon dioxide, a multi-directional downhole electrode device, and a ground detection device;

[0005] The multi-directional downhole electrode equipment includes a cable installed outside the non-conductive casing and an electrode array with a preset number of directions;

[0006] Each electrode array includes a preset number of metal electrodes arranged in the same position and vertically inserted into a non-conductive tube, and the metal electrodes are connected to a cable;

[0007] The ground detection equipment includes a current source, a transmitting device, an underground telecommunication system detection module and a computer central control.

[0008] In some preferred embodiments, the metal electrodes arranged in the same orientation and vertically inserted into the non-conductive tube include: n metal electrodes equally spaced and facing the same orientation, where n is an even number.

[0009] In another aspect of the present invention, a system for real-time detection of the geological storage status of carbon dioxide is proposed, comprising: a detection equipment installation module, a voltage measurement module, a resistance inversion module, a CO2 state evaluation module, a CO2 regional distribution evaluation module and a continuous real-time measurement module;

[0010] The detection equipment installation module is configured to grout the multi-directional downhole electrode equipment at multiple test well locations by conventional oilfield methods so that all cables and electrode arrays are buried in cement outside the casing;

[0011] Arrange a ground detection device at a ground position corresponding to each multi-directional downhole electrode device, so that the ground detection device is connected to the multi-directional downhole electrode device;

[0012] The voltage measurement module is configured to select a transmitting electrode and a receiving electrode through a ground detection device, emit a detection current of a preset waveform from the transmitting electrode, receive the lost detection current through the receiving electrode, obtain the potential difference between the electrodes, select another transmitting electrode and a receiving electrode combination to measure the potential difference between the electrodes, and form all the potential differences between the electrodes in one direction into a voltage data set for one direction;

[0013] The resistance inversion module is configured to obtain a voltage data set in the one direction through a ground detection device, and invert to obtain a resistivity grid distribution image based on the voltage data set in the one direction;

[0014] The CO2 state evaluation module is configured to calculate the CO2 distribution state of a direction according to the resistivity grid distribution image;

[0015] The azimuthal CO2 distribution states obtained by downhole electrode devices at all azimuthal positions outside the same non-conductive casing are combined to obtain the overall distribution state of CO2 in a single well;

[0016] The CO2 regional distribution evaluation module combines the overall distribution states of CO2 of all the test wells to obtain the CO2 regional distribution state;

[0017] The continuous real-time measurement module is configured to repeat the functions of the voltage measurement module, the resistance inversion module, the CO2 state evaluation module and the CO2 regional distribution evaluation module to obtain CO2 regional distribution real-time data and CO2 regional distribution change data.

[0018] In some preferred embodiments, the voltage measurement module includes a single electrode emission measurement mode, specifically:

[0019] Select any metal electrode as the transmitting electrode, and the remaining n-1 electrodes as the receiving electrodes, and record the inter-electrode potential difference of each group of transmitting electrode and receiving electrode as the single electrode transmitting measurement potential difference;

[0020] Another metal electrode that has not been selected is selected as the transmitting electrode, and the potential difference between each group of transmitting electrode and receiving electrode is measured until all metal electrodes are selected as transmitting electrodes and the single electrode transmitting measurement potential difference is recorded.

[0021] In some preferred embodiments, the voltage measurement module further includes a symmetrical electrode emission measurement mode, specifically:

[0022] The center of the length of the non-conductive sleeve is selected as the symmetry axis, and the metal electrodes with the same distance from the symmetry axis are used as a metal electrode pair;

[0023] Select any metal electrode pair as the transmitting electrode pair, and the remaining n-2 electrodes as the receiving electrodes, and record the inter-electrode potential difference between each group of transmitting electrode pair and receiving electrode as the symmetrical electrode transmitting measurement potential difference;

[0024] Another metal electrode pair that has not been selected is selected as the transmitting electrode, and the inter-electrode potential difference of each group of transmitting electrode pairs and receiving electrodes is measured until all metal electrodes are selected as transmitting electrode pairs and the symmetrical electrode transmitting measurement potential difference is recorded.

[0025] In some preferred embodiments, the voltage measurement module further includes a long-distance detection mode, specifically:

[0026] Select two electrodes A and B with a preset interval of k electrodes as high voltage transmitting electrodes, where k is an even number;

[0027] Select two electrodes C and D between electrodes A and B as high-voltage transmitting electrodes, and A, B, C and D constitute a high-voltage transmitting electrode group;

[0028] The high voltage detection current is emitted through the high voltage transmitting electrode, and the remaining n-4 electrodes are used as receiving electrodes. The potential difference between each high voltage transmitting electrode group and the receiving electrode is recorded as the long-distance detection potential difference;

[0029] Select the metal electrode combination that has not been selected as the high-voltage transmitting electrode group, measure the potential difference between each high-voltage transmitting electrode group and the receiving electrode until all possible high-voltage metal electrode combinations are selected and record the long-distance detection potential difference.

[0030] In some preferred embodiments, the voltage measurement module further includes a drop attenuation long-distance detection mode, specifically:

[0031] Select two electrodes E and F with a preset interval of q electrodes as low-voltage transmitting electrodes, where q is an even number;

[0032] The two electrodes G and H between electrodes E and F are selected as high-voltage transmitting electrodes, and E, F, G and H are selected as the attenuation-reducing long-distance detection transmitting electrode group;

[0033] A low-voltage detection current is emitted through the low-voltage transmitting electrode, and a high-voltage detection current is emitted through the high-voltage transmitting electrode. At this time, the potential difference between the two receiving electrodes close to the low-voltage transmitting electrode between the high-voltage transmitting electrode and the low-voltage transmitting electrode is 0, and the remaining n-4 electrodes are used as receiving electrodes. The potential difference between each attenuation long-distance detection transmitting electrode group and the receiving electrode is recorded as the attenuation long-distance detection potential difference;

[0034] Select the unselected metal electrode combinations as the attenuation-reducing long-distance detection transmitting electrode group, measure the inter-electrode potential difference between each attenuation-reducing long-distance detection transmitting electrode group and the receiving electrode until all possible metal electrode combinations are selected and the attenuation-reducing long-distance detection potential difference is recorded.

[0035] In some preferred implementations, the obtaining of the voltage data set in one direction by using a ground detection device specifically includes:

[0036] Connect the metal electrodes to the transmitter and downhole telecommunication system detection module through a multiplexer and cables;

[0037] The computer controls the transmitter to emit a current of a preset waveform and records the current received by the downhole telecommunication system detection module, thereby obtaining the potential difference between the electrodes.

[0038] In some preferred embodiments, the azimuthal CO2 state is calculated based on the resistivity solution distribution image, specifically, in the CO2 supercritical area, the formation resistivity increases by 5 times compared with before oil recovery.

[0039] In some preferred embodiments, the detection current of a preset waveform is emitted from the transmitting electrode, and the lost detection current is received by the receiving electrode to obtain the potential difference between the electrodes, specifically:

[0040] The frequency ω of the transmitted alternating current is given by Ohm's law:

[0041] V(ω)=I(ω)Z(ω)

[0042] Wherein, Z(ω) represents complex impedance, V(ω) represents voltage, and I(ω) represents current.

[0043] The third aspect of the present invention provides a method for real-time detection of the state of geological storage of CO2, comprising:

[0044] Step S100, grouting the multi-directional downhole electrode equipment at multiple test well locations by conventional oilfield methods, so that all cables and electrode arrays are buried in cement outside the casing, and the ground detection equipment is connected to the multi-directional downhole electrode equipment;

[0045] Arrange ground detection equipment at the ground position corresponding to each multi-directional downhole electrode equipment;

[0046] Step S200, selecting a transmitting electrode and a receiving electrode through a ground detection device, emitting a detection current of a preset waveform from the transmitting electrode, receiving the lost detection current through the receiving electrode, obtaining the potential difference between the electrodes, selecting another transmitting electrode and a receiving electrode combination to measure the potential difference between the electrodes, and combining all the potential differences between the electrodes in one direction into a voltage data set for one direction;

[0047] Step S300, obtaining a voltage data set at one direction through ground detection equipment, and obtaining a resistivity grid distribution image based on the voltage data set at one direction by inversion;

[0048] Step S400, calculating a CO2 grid state of a direction according to the resistivity grid distribution image;

[0049] The azimuth CO2 grid states obtained by downhole electrode equipment at all azimuths outside the same non-conductive casing are combined to obtain the overall distribution state of CO2 in a single well;

[0050] Step S500, combining the overall distribution of CO2 status of all the tested wells to obtain the CO2 regional distribution;

[0051] Step S600, repeating steps S200-S500 to obtain CO2 regional distribution real-time data and CO2 regional distribution change data.

[0052] In a fourth aspect of the present invention, an electronic device is proposed, comprising: at least one processor; and a memory communicatively connected to at least one of the processors; wherein the memory stores instructions executable by the processor, and the instructions are used to be executed by the processor to implement the above-mentioned method for real-time detection of the geological storage status of carbon dioxide.

[0053] In a fifth aspect of the present invention, a computer central control readable storage medium is proposed, wherein the computer central control readable storage medium stores computer central control instructions, and the computer central control instructions are used to be executed by the computer central control to implement the above-mentioned method for real-time detection of the geological storage status of carbon dioxide.

[0054] Beneficial effects of the present invention:

[0055] (1) The present invention achieves large-scale real-time detection of the CO2 geological storage status by depicting the resistivity differences of geological bodies with high resolution.

[0056] (2) The present invention achieves the measurement of the spatial distribution and change of the resistance of a highly heterogeneous geological body by deploying a multi-directional electrode array and ground detection equipment at the logging well site, thereby detecting CO2 plumes and possible leakage.

[0057] (3) The present invention sets up a combination of transmitting electrodes and receiving electrodes in multiple modes and sets up a unique detection method. The potential difference between electrodes measured in multiple modes is used to invert the CO2 distribution state. It can accurately reflect the change trend of resistance in the vertical direction, accurately observe the sudden change of geological resistance, and timely discover the leakage of carbon dioxide.

[0058] (4) The present invention sets a unique voltage detection mode and selects relevant electrodes to emit high-voltage detection current, so that the regional current between the relevant electrodes will not diffuse and decay in irrelevant directions, thereby improving the detection range of the detection current and being able to observe the CO2 geological storage status in a more comprehensive and larger range in real time to address the problem of the spatial distribution and change of resistance of highly heterogeneous geological bodies. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0060] Figure 1 It is a principle block diagram of the system for real-time detection of geological storage status of carbon dioxide of the present invention;

[0061] Figure 2 Schematic diagram of the principle of ground detection equipment for real-time detection of the geological storage state of carbon dioxide in an embodiment of the present invention;

[0062] Figure 3 is a schematic diagram of placement of downhole electrode equipment in a formation in an embodiment of the present invention;

[0063] Figure 4 It is a schematic diagram of a resistivity grid distribution image obtained by inverting a voltage data set in one direction in an embodiment of the present invention;

[0064] Figure 5 is a resistivity grid distribution diagram in an embodiment of the present invention;

[0065] Figure 6 Schematic diagram of the overall distribution of CO2 in a single well in an embodiment of the present invention;

[0066] Figure 7 Schematic diagram of the distribution of CO2 in a single well in geology in an embodiment of the present invention. DETAILED DESCRIPTION

[0067] The present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than to limit the invention. It is also necessary to explain that, for ease of description, only the parts related to the relevant invention are shown in the accompanying drawings.

[0068] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0069] The present invention provides a device for real-time detection of the geological storage state of carbon dioxide. The device can depict the resistivity difference of geological bodies in a large range with high resolution, and can realize large-scale and accurate real-time detection of the geological storage state of CO2.

[0070] Including multi-directional downhole electrode equipment and ground detection equipment;

[0071] The multi-directional downhole electrode equipment includes a cable installed outside the non-conductive casing and an electrode array with a preset number of directions;

[0072] Each electrode array includes a preset number of metal electrodes arranged in the same position and vertically inserted into the non-conductive tube, and the metal electrodes are connected to the cable; different electrode arrays are provided with metal electrodes at the same height;

[0073] The ground detection equipment includes a current source, a transmitting device, an underground telecommunication system detection module and a computer central control.

[0074] Also provided is a system for real-time detection of CO2 geological storage status, which can be applied to a device for real-time detection of CO2 geological storage status, comprising: a detection equipment installation module, a voltage measurement module, a resistance inversion module, a CO2 status evaluation module, a CO2 regional distribution evaluation module and a continuous real-time measurement module;

[0075] The detection equipment installation module is configured to grout the multi-directional downhole electrode equipment at multiple test well locations by conventional oilfield methods so that all cables and electrode arrays are buried in cement outside the casing;

[0076] Arrange a ground detection device at a ground position corresponding to each multi-directional downhole electrode device, so that the ground detection device is connected to the multi-directional downhole electrode device;

[0077] The voltage measurement module is configured to select a transmitting electrode and a receiving electrode through a ground detection device, emit a detection current of a preset waveform from the transmitting electrode, receive the lost detection current through the receiving electrode, obtain the potential difference between the electrodes, select another transmitting electrode and a receiving electrode combination to measure the potential difference between the electrodes, and form all the potential differences between the electrodes in one direction into a voltage data set for one direction;

[0078] The resistance inversion module is configured to obtain a voltage data set at the one orientation through a ground detection device, and obtain a resistivity grid distribution image based on the voltage data set at the one orientation through inversion;

[0079] The CO2 state evaluation module is configured to calculate the CO2 distribution state of a direction according to the resistivity grid distribution image;

[0080] The azimuthal CO2 distribution states obtained by downhole electrode devices at all azimuths outside the same non-conductive casing are combined to obtain the overall CO2 distribution state of a single well;

[0081] The CO2 regional distribution evaluation module combines the overall distribution states of CO2 of all the test wells to obtain the CO2 regional distribution state;

[0082] The continuous real-time measurement module is configured to repeat the functions of the voltage measurement module, the resistance inversion module, the CO2 state evaluation module and the CO2 regional distribution evaluation module to obtain CO2 regional distribution real-time data and CO2 regional distribution change data.

[0083] In order to more clearly explain the system for real-time detection of CO2 geological storage status of the present invention, the following is combined with Figure 1 Each functional module in the embodiment of the present invention is described in detail.

[0084] The system for real-time detection of CO2 geological storage status in the first embodiment of the present invention includes a detection equipment installation module, a voltage measurement module, a resistance inversion module, a CO2 status evaluation module and a CO2 regional distribution evaluation module. The functional modules are described in detail as follows:

[0085] The detection equipment installation module is configured to grout the multi-directional downhole electrode equipment in multiple test wells by traditional oilfield methods, so that all cables and electrode arrays are buried in cement outside the casing; this embodiment uses Ohm's law to calculate the voltage between any two electrodes to measure the formation resistivity. Because the underground components are mainly composed of metal electrodes and cables in non-conductive casings for connecting the surface current source and the downhole telecommunication system detection module equipment, it has a more reliable mechanical structure.

[0086] In this embodiment, the number of directions can be set to any number of 4 directions, 8 directions or 16 directions according to the detection accuracy requirement.

[0087] Arrange ground detection equipment at the ground position corresponding to each multi-directional downhole electrode equipment;

[0088] In this embodiment, the multi-directional downhole electrode device includes a cable installed outside the non-conductive casing and an electrode array with a preset number of directions;

[0089] Wherein, each electrode array includes a preset number of vertical metal electrodes arranged in the same orientation;

[0090] In this embodiment, the vertical metal electrodes arranged in the same orientation include: n metal electrodes with equal spacing and facing the same orientation, where n is an even number. In this embodiment, preferably 32 metal electrodes are arranged in each orientation. In this embodiment, the downhole electrode equipment arranged is as follows: Figure 3 shown.

[0091] The ground detection equipment includes a power supply, a transmitting device, an underground telecommunication system detection module and a computer central control, such as Figure 2 As shown, the power supply is connected to the transmitting device, and the transmitting device is connected to the downhole sensor detection module through the voltage transmitting circuit and the voltage feedback circuit. The voltage feedback circuit is also connected to the potential measuring resistor, and the two ends of the potential measuring resistor are connected to the electrical signal processing module. The electrical signal processing module is simultaneously connected to the computer central control, the downhole sensor detection module and the transmitting device through the timer, and the downhole sensor detection module is additionally directly connected to the electrical signal processing module.

[0092] The voltage measurement module is configured to select a transmitting electrode and a receiving electrode through a ground detection device, emit a detection current of a preset waveform from the transmitting electrode, receive the lost detection current through the receiving electrode, and obtain the potential difference between the electrodes; in this embodiment, in order to reduce the interference of electromagnetic induction in a long cable (2 miles), preferably, a square wave current with a frequency lower than 1 Hz is selected as the detection current, and multiple frequencies of detection currents or detection currents with waveform superposition can also be set to improve the additional measurement required for the signal-to-noise ratio;

[0093] In this embodiment, the detection current of a preset waveform is emitted from the transmitting electrode, and the detection current is lost by the receiving electrode to obtain the potential difference between the electrodes, and all the potential differences between the electrodes in one direction are combined into a voltage data set in one direction:

[0094] The frequency ω of the transmitted alternating current is given by Ohm's law:

[0095] V(ω)=I(ω)Z(ω)

[0096] Wherein, Z(ω) represents complex impedance, V(ω) represents voltage, and I(ω) represents current.

[0097] In this embodiment, the voltage measurement module includes a single-electrode emission measurement mode, specifically:

[0098] Select any metal electrode as the transmitting electrode, and the remaining n-1 electrodes as the receiving electrodes, and record the inter-electrode potential difference of each group of transmitting electrode and receiving electrode as the single electrode transmitting measurement potential difference;

[0099] Select another metal electrode that has not been selected as the transmitting electrode, measure the potential difference between each group of transmitting electrodes and receiving electrodes until all metal electrodes are selected as transmitting electrodes and record the single electrode transmitting measurement potential difference. For example, select electrode 1 as the transmitting electrode. At this time, electrodes 2 to 32 can all receive the attenuated detection current. Select electrodes 1 to 32 as transmitting electrodes and record the potential difference. This step can obtain an accurate resistivity distribution map.

[0100] In this embodiment, the voltage measurement module further includes a symmetrical electrode emission measurement mode, specifically:

[0101] The center of the length of the non-conductive sleeve is selected as the symmetry axis, and the metal electrodes with the same distance from the symmetry axis are used as a metal electrode pair;

[0102] Select any metal electrode pair as the transmitting electrode pair, and the remaining n-2 electrodes as the receiving electrodes, and record the inter-electrode potential difference between each group of transmitting electrode pair and receiving electrode as the symmetrical electrode transmitting measurement potential difference;

[0103] Select another metal electrode pair that has not been selected as the transmitting electrode, measure the potential difference between each group of transmitting electrode pairs and receiving electrodes until all metal electrodes are selected as transmitting electrode pairs and record the symmetrical electrode transmission measurement potential difference. For example, if electrode No. 16 and electrode No. 17 are selected as transmitting electrodes, then electrodes No. 1 to 15 and electrodes No. 18 to 32 are selected as receiving electrodes, and record the potential differences of all combinations. The detection method of this step can obtain the resistivity distribution at medium distances.

[0104] In this embodiment, the voltage measurement module further includes a long-distance detection mode, specifically:

[0105] Select two electrodes A and B with a preset interval of k electrodes as high voltage transmitting electrodes, where k is an even number;

[0106] Select two electrodes C and D between electrodes A and B as high-voltage transmitting electrodes, and A, B, C and D constitute a high-voltage transmitting electrode group;

[0107] The high voltage detection current is emitted through the high voltage transmitting electrode, and the remaining n-4 electrodes are used as receiving electrodes. The potential difference between each high voltage transmitting electrode group and the receiving electrode is recorded as the long-distance detection potential difference;

[0108] Select the metal electrode combination that has not been selected as the high-voltage transmitting electrode group, measure the potential difference between each high-voltage transmitting electrode group and the receiving electrode until all possible high-voltage metal electrode combinations are selected and record the long-distance detection potential difference. For example, select the 10th electrode and the 20th electrode as the high-voltage transmitting electrode, select the 15th and 16th electrodes in the middle as the high-voltage transmitting electrodes, and create the same potential of the 10th and 20th electrodes through the high-voltage transmitting electrodes to avoid the lateral attenuation of the detection current of the 15th and 16th high-voltage transmitting electrodes in the middle, so that the long-distance resistance distribution can be obtained. Adjust various possible long-distance detection combinations to obtain the long-distance resistance distribution at various depths.

[0109] In this embodiment, the voltage measurement module further includes a drop attenuation long-distance detection mode, specifically:

[0110] Select two electrodes E and F with a preset interval of q electrodes as low-voltage transmitting electrodes, where q is an even number;

[0111] The two electrodes G and H between electrodes E and F are selected as high-voltage transmitting electrodes, and E, F, G and H are selected as the attenuation-reducing long-distance detection transmitting electrode group;

[0112] A low-voltage detection current is emitted through the low-voltage transmitting electrode, and a high-voltage detection current is emitted through the high-voltage transmitting electrode. At this time, the potential difference between the two receiving electrodes close to the low-voltage transmitting electrode between the high-voltage transmitting electrode and the low-voltage transmitting electrode is 0, and the remaining n-4 electrodes are used as receiving electrodes. The potential difference between each attenuation long-distance detection transmitting electrode group and the receiving electrode is recorded as the attenuation long-distance detection potential difference;

[0113] Select the unselected metal electrode combination as the attenuation-reduced long-distance detection transmitting electrode group, measure the potential difference between each attenuation-reduced long-distance detection transmitting electrode group and the receiving electrode until all possible metal electrode combinations are selected and record the attenuation-reduced long-distance detection potential difference. For example, select electrodes 15 and 16 as high-voltage transmitting electrodes, and select electrodes 10 and 20 as low-voltage transmitting electrodes. At this time, the potential difference between electrodes 11 and 12 and electrodes 18 and 19 is 0, so that while obtaining the long-distance resistance, it can also accurately reflect the resistivity changes at different depths. Adjust various possible long-distance detection combinations to obtain the distribution of attenuation-reduced long-distance resistance at each depth.

[0114] In this embodiment, the current injection electrodes and voltages for all possible measurement combinations are linearly independent.

[0115] The resistance inversion module is configured to obtain a voltage data set in the one direction through a ground detection device, and invert to obtain a resistivity grid distribution image based on the voltage data set in the one direction;

[0116] In this embodiment, the obtaining of the voltage data set in one direction by using a ground detection device specifically includes:

[0117] Connecting the electrodes to the transmitter and the downhole electrical system detection module through a multiplexer;

[0118] The computer controls the transmitter to emit a current of a preset waveform and records the current received by the downhole telecommunication system detection module, thereby obtaining the potential difference between the electrodes.

[0119] After obtaining the potential differences between the electrodes, only solutions with expected characteristics, such as maximum smoothness, can be considered. Preferably, the smoothness of the solutions is specified to be anisotropic and smaller in the vertical direction, as expected when the CO2 plume moves along more or less horizontal adjacent geohydrological layers.

[0120] The resistance inversion module is configured to obtain a voltage data set at one position through a ground detection device, and obtain a resistivity grid distribution image based on the voltage data set at one position by inversion, such as Figure 4 As shown;

[0121] The CO2 state evaluation module is configured to calculate the CO2 state of an orientation based on the resistivity grid distribution image; the presence of interwell plumes is easily detected, and in the absence of much higher electrode spatial resolution, any finer scale structure of the plume with the electrical characteristics assumed here will be difficult to detect. The resistivity increases significantly after the CO2 plume flows.

[0122] In this embodiment, the azimuthal CO2 state is calculated based on the resistivity solution distribution image, specifically, in the area where CO2 is supercritical, the formation resistivity is n times the preset value before oil recovery, and preferably n is 5.

[0123] The azimuth CO2 distribution states obtained by the downhole electrode equipment at all azimuths outside the same non-conductive casing are combined to obtain the overall distribution of CO2 state in a single well. However, the resistance grid distribution of the well is as follows: Figure 5 As shown, it is converted into the overall distribution of CO2 state of a single well as shown in Figure 6 As shown;

[0124] The CO2 regional distribution evaluation module combines the overall distribution of CO2 status of single wells of all test well locations to obtain the CO2 regional distribution;

[0125] The continuous real-time measurement module is configured to repeat the functions of the voltage measurement module, the resistance inversion module, the CO2 state evaluation module and the CO2 regional distribution evaluation module, and obtains the CO2 regional distribution real-time data and the CO2 regional distribution change data. The change of the CO2 difference reflects whether there is a CO2 leak. If CO2 is found to be rapidly accumulated, it is considered that a leak has occurred. The comparison between the good CO2 storage state and the leak detected by the present invention is as follows: Figure 7 As shown, it can be seen that when the CO2 storage state is good, CO2 should flow in the formation, but not through the formation; when CO2 leaks, the resistance in the horizontal direction will increase significantly in a certain area, but the range will be reduced, while the high resistance range in the vertical direction will increase; in the case of good preservation, the resistance of the formation will have obvious formation resistance boundaries, and when there is a leakage, a high resistance area will appear that runs through the original formation resistance boundary. Therefore, improving the detection range of formation carbon dioxide and improving the resistance detection accuracy in the vertical direction are of great significance for observing the flow of carbon dioxide. Compared with the existing geological resistivity measurement method, this application obtains a larger range and higher precision resistance distribution by setting an electrode array according to the orientation and obtaining the potential difference of all possible combinations. Furthermore, since each downhole equipment is divided into different orientations for measurement, it can reflect the resistance change trend in the longitudinal and horizontal directions of the detection equipment, and can observe the flow of CO2 in different orientations, and can measure the range of changes in the CO2 plume, and perform real-time measurement.

[0126] It should be noted that the system for real-time detection of the geological storage status of CO2 provided in the above embodiment is only illustrated by the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the modules or steps in the embodiments of the present invention can be decomposed or combined. For example, the modules in the above embodiment can be combined into one module, or further divided into multiple sub-modules to complete all or part of the functions described above. The names of the modules and steps involved in the embodiments of the present invention are only for distinguishing the modules or steps, and are not regarded as improper limitations of the present invention.

[0127] The method for real-time detection of CO2 geological storage status according to the third embodiment of the present invention includes steps S100 to S600, each of which is described in detail as follows:

[0128] Step S100, grouting the multi-directional downhole electrode equipment at multiple test well locations by conventional oilfield methods, so that all cables and electrode arrays are buried in cement outside the casing;

[0129] Arrange a ground detection device at a ground position corresponding to each multi-directional downhole electrode device, so that the ground detection device is connected to the multi-directional downhole electrode device;

[0130] Step S200, selecting a transmitting electrode and a receiving electrode through a ground detection device, emitting a detection current of a preset waveform from the transmitting electrode, receiving the lost detection current through the receiving electrode, obtaining the potential difference between the electrodes, selecting another transmitting electrode and a receiving electrode combination to measure the potential difference between the electrodes, and combining all the potential differences between the electrodes in one direction into a voltage data set for one direction;

[0131] Step S300, obtaining a voltage data set at one direction through ground detection equipment, and obtaining a resistivity grid distribution image based on the voltage data set at one direction by inversion;

[0132] Step S400, calculating the CO2 distribution state in one direction according to the resistivity grid distribution image;

[0133] The azimuthal CO2 distribution states obtained by downhole electrode devices at all azimuths outside the same non-conductive casing are combined to obtain the overall CO2 distribution state of a single well;

[0134] Step S500, combining the overall distribution of CO2 status of all the tested wells to obtain the CO2 regional distribution;

[0135] Step S600, repeating steps S200-S500 to obtain CO2 regional distribution real-time data and CO2 regional distribution change data.

[0136] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process and related instructions of the system described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0137] An electronic device according to a fourth embodiment of the present invention includes: at least one processor; and a memory connected to the at least one processor in communication; wherein:

[0138] The memory stores instructions that can be executed by the processor, and the instructions are used to be executed by the processor to implement the above-mentioned method for real-time detection of CO2 geological storage status.

[0139] A computer central control readable storage medium according to a fourth embodiment of the present invention stores computer central control instructions, and the computer central control instructions are used to be executed by the computer central control to implement the above-mentioned method for real-time detection of CO2 geological storage status.

[0140] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process and related instructions of the storage device and processing device described above can refer to the corresponding process in the aforementioned method embodiment and will not be repeated here.

[0141] The terms "first", "second", etc. are used to distinguish similar objects rather than to describe or indicate a particular order or sequence.

[0142] The term "comprise" or any other similar term is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus / device that includes a list of elements includes not only those elements but also other elements not expressly listed, or also includes elements inherent to such process, method, article, or apparatus / device.

[0143] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A system for real-time detection of the geological storage status of carbon dioxide, characterized in that: Using a device to detect the geological storage status of carbon dioxide in real time, The device for real-time detection of the geological storage status of carbon dioxide includes: multi-directional downhole electrode equipment and ground detection equipment; The multi-directional downhole electrode equipment includes a cable installed outside the non-conductive casing and an electrode array with a preset number of directions; Each electrode array includes a preset number of metal electrodes arranged in the same position and vertically inserted into a non-conductive tube, and the metal electrodes are connected to a cable; The ground detection equipment includes a current source, a transmitting device, an underground telecommunication system detection module and a computer central control; The metal electrodes arranged in the same orientation and vertically inserted into the non-conductive tube include: n metal electrodes equally spaced and facing the same orientation, where n is an even number; The system includes: a detection equipment installation module, a voltage measurement module, a resistance inversion module, a CO2 state evaluation module, a CO2 regional distribution evaluation module and a continuous real-time measurement module; The detection equipment installation module is configured to grout the multi-directional downhole electrode equipment at multiple test well locations by conventional oilfield methods so that all cables and electrode arrays are buried in cement outside the casing; Arrange a ground detection device at a ground position corresponding to each multi-directional downhole electrode device, so that the ground detection device is connected to the multi-directional downhole electrode device; The voltage measurement module is configured to select a transmitting electrode and a receiving electrode through a ground detection device, emit a detection current of a preset waveform from the transmitting electrode, receive the lost detection current through the receiving electrode, obtain the potential difference between the electrodes, select another transmitting electrode and a receiving electrode combination to measure the potential difference between the electrodes, and form all the potential differences between the electrodes in one direction into a voltage data set in one direction; the resistance inversion module is configured to obtain the voltage data set in the one direction through the ground detection device, and obtain the resistivity grid distribution image based on the voltage data set in the one direction by inversion; The CO2 state evaluation module is configured to calculate the CO2 distribution state of a direction according to the resistivity grid distribution image; The azimuthal CO2 distribution states obtained by downhole electrode devices at all azimuths outside the same non-conductive casing are combined to obtain the overall CO2 distribution state of a single well; The CO2 regional distribution evaluation module combines the overall distribution states of CO2 of all the test wells to obtain the CO2 regional distribution state; The continuous real-time measurement module is configured to repeat the functions of the voltage measurement module, the resistance inversion module, the CO2 state evaluation module and the CO2 regional distribution evaluation module to obtain CO2 regional distribution real-time data and CO2 regional distribution change data.

2. The system for real-time detection of geological storage status of carbon dioxide according to claim 1, characterized in that: The voltage measurement module includes a single-electrode emission measurement mode, specifically: Select any metal electrode as the transmitting electrode, and the remaining n-1 electrodes as the receiving electrodes, and record the inter-electrode potential difference of each group of transmitting electrode and receiving electrode as the single electrode transmitting measurement potential difference; Another metal electrode that has not been selected is selected as the transmitting electrode, and the potential difference between each group of transmitting electrode and receiving electrode is measured until all metal electrodes are selected as transmitting electrodes and the single electrode transmitting measurement potential difference is recorded.

3. The system for real-time detection of geological storage status of carbon dioxide according to claim 2, characterized in that: The voltage measurement module also includes a symmetrical electrode emission measurement mode, specifically: The center of the length of the non-conductive sleeve is selected as the symmetry axis, and the metal electrodes with the same distance from the symmetry axis are used as a metal electrode pair; Select any metal electrode pair as the transmitting electrode pair, and the remaining n-2 electrodes as the receiving electrodes, and record the inter-electrode potential difference between each group of transmitting electrode pair and receiving electrode as the symmetrical electrode transmitting measurement potential difference; Another metal electrode pair that has not been selected is selected as the transmitting electrode, and the inter-electrode potential difference of each group of transmitting electrode pairs and receiving electrodes is measured until all metal electrodes are selected as transmitting electrode pairs and the symmetrical electrode transmitting measurement potential difference is recorded.

4. The system for real-time detection of geological storage status of carbon dioxide according to claim 2, characterized in that: The voltage measurement module also includes a long-distance detection mode, specifically: Select two electrodes A and B with a preset interval of k electrodes as high voltage transmitting electrodes, where k is an even number; Select two electrodes C and D between electrodes A and B as high-voltage transmitting electrodes, and A, B, C and D constitute a high-voltage transmitting electrode group; The high voltage detection current is emitted through the high voltage transmitting electrode, and the remaining n-4 electrodes are used as receiving electrodes. The potential difference between each high voltage transmitting electrode group and the receiving electrode is recorded as the long-distance detection potential difference; Select the metal electrode combination that has not been selected as the high-voltage transmitting electrode group, measure the potential difference between each high-voltage transmitting electrode group and the receiving electrode until all possible high-voltage metal electrode combinations are selected and record the long-distance detection potential difference.

5. The system for real-time detection of geological storage status of carbon dioxide according to claim 2, characterized in that: The voltage measurement module also includes a drop attenuation long-distance detection mode, specifically: Select two electrodes E and F with a preset interval of q electrodes as low-voltage transmitting electrodes, where q is an even number; The two electrodes G and H between electrodes E and F are selected as high-voltage transmitting electrodes, and E, F, G and H are selected as the attenuation-reducing long-distance detection transmitting electrode group; A low-voltage detection current is emitted through the low-voltage transmitting electrode, and a high-voltage detection current is emitted through the high-voltage transmitting electrode. At this time, the potential difference between the two receiving electrodes close to the low-voltage transmitting electrode between the high-voltage transmitting electrode and the low-voltage transmitting electrode is 0, and the remaining n-4 electrodes are used as receiving electrodes. The potential difference between each attenuation long-distance detection transmitting electrode group and the receiving electrode is recorded as the attenuation long-distance detection potential difference; Select the unselected metal electrode combinations as the attenuation-reducing long-distance detection transmitting electrode group, measure the inter-electrode potential difference between each attenuation-reducing long-distance detection transmitting electrode group and the receiving electrode until all possible metal electrode combinations are selected and the attenuation-reducing long-distance detection potential difference is recorded.

6. The system for real-time detection of geological storage status of carbon dioxide according to claim 1, characterized in that: The step of obtaining the voltage data set at the one position by using the ground detection equipment specifically includes: Connect the metal electrodes to the transmitter and downhole telecommunication system detection module through a multiplexer and cables; The computer controls the transmitter to emit a current of a preset waveform and records the current received by the downhole telecommunication system detection module, thereby obtaining the potential difference between the electrodes.

7. The system for real-time detection of geological storage status of carbon dioxide according to claim 1, characterized in that: The detection current of a preset waveform is emitted from the transmitting electrode, and the lost detection current is received by the receiving electrode to obtain the potential difference between the electrodes, specifically: The frequency ω of the transmitted alternating current is given by Ohm's law: V(ω)=I(ω)Z(ω) Wherein, Z(ω) represents complex impedance, V(ω) represents voltage, and I(ω) represents current.

8. A method for real-time detection of the geological storage status of carbon dioxide, characterized in that: A device for real-time detection of the geological storage status of carbon dioxide is used, and the device for real-time detection of the geological storage status of carbon dioxide includes: multi-directional downhole electrode equipment and ground detection equipment; The multi-directional downhole electrode equipment includes a cable installed outside the non-conductive casing and an electrode array with a preset number of directions; Each electrode array includes a preset number of metal electrodes arranged in the same position and vertically inserted into a non-conductive tube, and the metal electrodes are connected to a cable; The ground detection equipment includes a current source, a transmitting device, an underground telecommunication system detection module and a computer central control; The metal electrodes arranged in the same orientation and vertically inserted into the non-conductive tube include: n metal electrodes equally spaced and facing the same orientation, where n is an even number; The method comprises: Step S100, grouting the multi-directional downhole electrode equipment at multiple test well locations by conventional oilfield methods, so that all cables and electrode arrays are buried in cement outside the casing; Arrange a ground detection device at a ground position corresponding to each multi-directional downhole electrode device, so that the ground detection device is connected to the multi-directional downhole electrode device; Step S200, selecting a transmitting electrode and a receiving electrode through a ground detection device, emitting a detection current of a preset waveform from the transmitting electrode, receiving the lost detection current through the receiving electrode, obtaining the potential difference between the electrodes, selecting another transmitting electrode and a receiving electrode combination to measure the potential difference between the electrodes, and combining all the potential differences between the electrodes in one direction into a voltage data set for one direction; Step S300, acquiring the voltage data set of the one direction through the ground detection device, and obtaining a resistivity grid distribution image based on the voltage data set of the one direction by inversion; Step S400, calculating the CO2 distribution state in one direction according to the resistivity grid distribution image; The azimuthal CO2 distribution states obtained by downhole electrode devices at all azimuths outside the same non-conductive casing are combined to obtain the overall CO2 distribution state of a single well; Step S500, combining the overall distribution of CO2 status of all the tested wells to obtain the CO2 regional distribution; Step S600, repeating steps S200-S500 to obtain CO2 regional distribution real-time data and CO2 regional distribution change data.

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