CO2 sealing and gas production collaboration device adaptive to tight gas horizontal well

Abstract

The invention discloses a CO2 sequestration and gas production collaborative device adaptive to a tight gas horizontal well, and relates to the technical field of gas production and carbon sequestration collaboration.The device comprises a reservoir state sensing module, an intelligent analysis regulation and control module, a CO2 injection regulation and control module, a pressure balance module and a gas production execution module; multi-dimensional data of reservoir stress, concentration and pressure are synchronously collected through the reservoir state sensing module, a multi-field coupling model of the intelligent analysis regulation and control module is combined, the problems that an existing device conducts regulation and control through a single parameter, and stress sensitivity of the tight gas reservoir is not considered are solved, an injection point is accurately adjusted through the CO2 injection regulation and control module, and the reliability of the device is improved. The pressure balance module and the gas production execution module cooperatively adjust the reservoir pressure, the problem of reservoir pressure unbalance is solved, finally, the gas production efficiency of the tight gas horizontal well and the CO2 storage safety are synchronously improved, and it is guaranteed that the cooperative target of energy development and carbon emission reduction is stably achieved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of gas extraction and carbon sequestration, and particularly relates to a CO2 sequestration and gas extraction coordination device suitable for a tight gas horizontal well. BACKGROUND

[0002] The tight gas horizontal well is a special well type for developing a tight gas reservoir, the tight gas reservoir has the characteristics of low porosity and low permeability, and the conventional straight well has great difficulty in exploitation and low efficiency, the tight gas horizontal well can greatly improve the exploitation efficiency of the tight gas by prolonging the contact length of the wellbore and the reservoir, is an important exploitation method for guaranteeing stable supply of natural gas energy and relieving energy supply and demand contradiction, and has important significance for promoting energy structure diversification and guaranteeing energy security, the CO2 sequestration and gas extraction is a technology for injecting CO2 into an underground reservoir, improving oil and gas recovery by using the displacement effect of CO2, and permanently sealing CO2 in the reservoir to realize the coordination of resource development and carbon emission reduction, the technology can improve the recovery efficiency of oil and gas resources, increase energy supply, effectively reduce the emission amount of CO2 in the atmosphere, and relieve the problem of global climate warming, is a key technical path for giving consideration to energy production and ecological environment protection, and has remarkable economic value and environmental significance.

[0003] However, the existing CO2 sequestration and gas extraction related device has certain defects in application to the tight gas horizontal well, the tight gas reservoir has strong stress sensitivity, and stress change of the reservoir easily leads to change of pore structure and deformation of seepage channel, the existing device is mainly based on single parameter of pressure or concentration for regulation and control, and the coupling influence of stress and concentration and seepage is not considered, the regulation and control precision is low, the single parameter regulation and control cannot timely respond to stress abnormality of the reservoir and CO2 migration change, and problems such as CO2 channeling along high stress cracks and reservoir pressure imbalance easily occur, which affects the gas extraction efficiency and the safety of CO2 sequestration, the device lacks an integrated sensing and regulation and control mechanism for the characteristics of the tight gas reservoir, real-time monitoring of the reservoir state and precise matching of regulation and control actions are difficult to realize, and the overall effect of the coordinated operation is limited, therefore, it is of great significance to develop the CO2 sequestration and gas extraction coordination device suitable for the tight gas horizontal well. SUMMARY

[0004] The purpose of the application is to make up for the deficiencies of the prior art, and provide the CO2 sequestration and gas extraction coordination device suitable for the tight gas horizontal well, which can realize synchronous acquisition of multi-dimensional data of reservoir stress, concentration and pressure through a reservoir state sensing module, solve the problems of single parameter regulation and control and not considering the stress sensitivity of the tight gas reservoir by combining a multi-field coupling model of an intelligent analysis and regulation and control module, accurately adjust an injection point through a CO2 injection regulation and control module to avoid CO2 channeling along high stress cracks, cooperatively adjust reservoir pressure through a pressure balance module and a gas extraction execution module to solve the problem of reservoir pressure imbalance, and realize synchronous improvement of the gas extraction efficiency of the tight gas horizontal well and the safety of CO2 sequestration.

[0005] The application provides a CO2 storage and gas production coordination device suitable for a compact gas horizontal well, which comprises a reservoir state sensing module, an intelligent analysis and control module, a CO2 injection control module, a pressure balance module and a gas production execution module. The reservoir state sensing module is arranged along a horizontal well bore and a key area of a reservoir, and is used for collecting reservoir temperature, strain, pressure and CO2 concentration data. The intelligent analysis and control module is connected with the reservoir state sensing module, the CO2 injection control module, the pressure balance module and the gas production execution module, and is provided with a stress-concentration-seepage multi-field coupling model, which is used for receiving and analyzing data transmitted by the reservoir state sensing module and generating control instructions. The CO2 injection control module is installed on a CO2 injection channel, and is used for adjusting a CO2 injection point and an injection state according to instructions of the intelligent analysis and control module. The pressure balance module is arranged along a horizontal well, and is used for releasing pressure of a high stress area of a reservoir according to instructions of the intelligent analysis and control module. The gas production execution module is connected with a gas production channel of the horizontal well, and is used for adjusting a gas production rate according to instructions of the intelligent analysis and control module.

[0006] Further, the reservoir state sensing module comprises a distributed optical fiber sensing unit and a multi-parameter monitoring unit, and when collecting reservoir data, the reservoir state sensing module comprises the following steps. The distributed optical fiber sensing unit is laid along a horizontal well bore and a key area of a reservoir, and a pressure sensor and a gas concentration sensor in the multi-parameter monitoring unit are respectively installed in different permeation areas of the reservoir and a gas production channel. The distributed optical fiber sensing unit is started to collect reservoir temperature and strain data. The multi-parameter monitoring unit is started synchronously, pressure data of the reservoir is collected by the pressure sensor, CO2 concentration data in the reservoir and the gas production channel are collected by the gas concentration sensor, and all collected data are transmitted to the intelligent analysis and control module in real time.

[0007] Further, the distributed optical fiber sensing unit adopts armored optical fiber, the armored optical fiber is wrapped with an anticorrosive wear-resistant coating, the armored optical fiber is laid along an inner wall of the horizontal well bore in a circumferential interval, and is laid in an encrypted manner in an area where a reservoir permeability difference is greater than a preset value.

[0008] Further, the pressure sensor and the gas concentration sensor in the multi-parameter monitoring unit are both provided with waterproof sealing structures, the detection end of the pressure sensor is arranged towards the reservoir pore direction, and the sampling port of the gas concentration sensor is communicated with the reservoir through a filter screen, and the pore size of the filter screen is smaller than the average pore size of the reservoir.

[0009] Further, the intelligent analysis and regulation module comprises a data receiving unit, a model operation unit and an instruction generating unit, and when processing data and generating regulation instructions, the intelligent analysis and regulation module comprises the following steps: receiving temperature, strain, pressure and CO2 concentration data transmitted by the reservoir state sensing module through the data receiving unit; inputting the received data into the model operation unit, first extracting reservoir strain measured values , pressure measured values , CO2 concentration measured values , then calling preset reservoir stable strain values , reservoir original pressure , CO2 safe concentration threshold , calculating a reservoir comprehensive state evaluation index through a stress-concentration-seepage multi-field coupling model , and the calculation formula is as follows: , wherein, is a strain deviation, is a pressure deviation, is a CO2 concentration deviation, , , are weight coefficients of strain, pressure and CO2 concentration on reservoir state evaluation respectively, , , obtaining stress-strain relationship data under different confining pressures through reservoir core triaxial compression experiments, combining CO2 storage and gas production historical operation data of more than 3 groups of same type tight gas horizontal wells on site, and adopting a partial least squares regression algorithm to fit and determine, so as to ensure that each coefficient matches the actual response characteristics of the reservoir, and then judging reservoir stress stability, CO2 migration trend and pressure balance state according to the numerical value of the reservoir comprehensive state evaluation index . The instruction generating unit generates regulation instructions for the CO2 injection regulation module, the pressure balance module and the gas production execution module respectively according to the analysis result of the model operation unit. The generated regulation instructions are transmitted to the corresponding CO2 injection regulation module, pressure balance module and gas production execution module respectively.

[0010] Furthermore, when performing computational analysis, the model computational unit will calculate the reservoir comprehensive state assessment index. Compared with the preset state threshold, when the reservoir comprehensive state assessment index When the value is less than a preset threshold, the reservoir is determined to be in a stable state. When the reservoir comprehensive state assessment index... If the value is greater than or equal to a preset threshold, the reservoir is determined to be in an abnormal state, and further analysis is performed based on strain deviation. Pressure deviation CO2 concentration deviation The parameter with the largest median value is used to determine the dominant factor in the anomaly.

[0011] Furthermore, the CO2 injection control module includes a main injection pipeline, branch injection pipelines, and an injection control valve assembly, and the CO2 injection control module includes the following steps when adjusting the CO2 injection point and injection state: Receive control commands transmitted by the intelligent analysis and control module, and determine the injection point to be adjusted and the corresponding injection parameters; Based on the determined injection point, locate the corresponding branch injection pipe and the control valve on that branch injection pipe; By controlling the opening degree of the corresponding control valve, the CO2 flow rate in the branch injection pipeline is adjusted to achieve the adjustment of the injection state; When it is necessary to switch injection points, close the control valve of the current branch injection pipeline and open the control valve of the target branch injection pipeline to complete the injection point switch.

[0012] Furthermore, the pressure balancing module includes a pressure relief pipeline and a pressure relief valve assembly. The pressure relief pipeline is segmented along the length of the horizontal well, with each segment corresponding to a specific stress region in the reservoir. One end of each pressure relief pipeline extends to the corresponding region in the reservoir, and the other end is connected to an external pressure relief system. The pressure relief valve assembly includes multiple pressure relief valves, each of which is installed on a corresponding segment of the pressure relief pipeline. Each pressure relief valve is connected to the intelligent analysis and control module for signal control of the opening, closing, and pressure relief rate of the corresponding pressure relief pipeline according to control commands.

[0013] Furthermore, the gas production execution module includes a gas production pipeline, a gas production regulating valve, and a flow monitoring component. The gas production pipeline is connected to the gas production channel of the horizontal well and is used to transport the extracted tight gas. The gas production regulating valve is installed on the gas production pipeline and is connected to the intelligent analysis and control module for signal connection. It is used to adjust the flow cross-sectional area of ​​the gas production pipeline according to the control command, thereby adjusting the gas production rate. The flow monitoring component is installed on the gas production pipeline and located downstream of the gas production regulating valve. It is used to monitor the gas flow rate in the gas production pipeline and transmit the flow data to the intelligent analysis and control module.

[0014] Compared with the prior art, the CO2 storage and gas recovery device for adapting to the compact gas horizontal well has the following beneficial effects: The present application realizes the multi-dimensional data synchronous collection of reservoir stress, concentration and pressure through the reservoir state sensing module, and solves the problems of single parameter regulation and the lack of consideration of the stress sensitivity of the compact gas reservoir by combining the multi-field coupling model of the intelligent analysis and regulation module, accurately adjusts the injection point through the CO2 injection regulation module, avoids the CO2 channeling along the high stress cracks, cooperatively adjusts the reservoir pressure through the pressure balance module and the gas recovery execution module, solves the problem of reservoir pressure imbalance, and finally realizes the synchronous improvement of the compact gas horizontal well gas recovery efficiency and the CO2 storage safety, and guarantees the stable achievement of the energy development and carbon emission reduction coordination targets.

[0015] Other advantages, objects, and features of the present application will be apparent to those skilled in the art from the following specification, and it is intended to be covered by the following claims. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creating any creative labor on the basis of these drawings.

[0017] Figure 1 The structure diagram of the CO2 storage and gas recovery device for adapting to the compact gas horizontal well; Figure 2 The work flow chart of the CO2 storage and gas recovery device for adapting to the compact gas horizontal well. DETAILED DESCRIPTION

[0018] In order to further illustrate the technical means and effects adopted by the present application to achieve the predetermined invention purpose, the specific embodiments, structures, features and effects according to the present application will be described in detail below with reference to the drawings and preferred embodiments.

[0019] The present application provides a CO2 storage and gas recovery device for adapting to the compact gas horizontal well, which aims to solve the problems of single parameter regulation and the lack of consideration of the stress sensitivity of the compact gas reservoir in the prior art, and realize the synchronous improvement of the gas recovery efficiency and the CO2 storage safety.

[0020] The device is composed of a reservoir state sensing module, an intelligent analysis and regulation module, a CO2 injection regulation module, a pressure balance module and a gas recovery execution module, and each module cooperatively works to form a complete technical solution, as shown in Figure 1 and Figure 2The specific content is as follows: The reservoir state sensing module is arranged along the horizontal well borehole and the key area of the reservoir, and contains a distributed optical fiber sensing unit and a multi-parameter monitoring unit. The distributed optical fiber sensing unit adopts armored optical fiber with corrosion-resistant and wear-resistant coating, is laid along the inner wall of the well borehole in a circumferential interval, and is densely arranged in the area with large difference in reservoir permeability, and is used for collecting temperature and strain data; the pressure sensor and the gas concentration sensor of the multi-parameter monitoring unit are both waterproof sealed structures, are respectively installed in different permeable areas of the reservoir and a gas production channel, the detection end of the pressure sensor faces the reservoir pore, the gas concentration sensor is connected with the reservoir through a filter screen smaller than the average pore diameter of the reservoir pore, and pressure and CO2 concentration data are synchronously collected, and all data are transmitted in real time.

[0021] The intelligent analysis and regulation module is signal-connected with the other four modules, and is internally provided with a stress-concentration-permeation multi-field coupling model, and contains a data receiving unit, a model operation unit and an instruction generating unit. After receiving the data of the reservoir state sensing module, the intelligent analysis and regulation module extracts the measured values and calls the preset standard values, calculates a reservoir comprehensive state evaluation index through the multi-field coupling model, compares the preset threshold to judge whether the reservoir is stable or not, if abnormal, determines the dominant factor according to the maximum deviation parameter, and then generates corresponding regulation instructions.

[0022] The CO2 injection regulation module is installed in the CO2 injection channel, is composed of an injection main pipeline, branch injection pipelines and an injection control valve group, adjusts the injection point and parameters according to the instructions, adjusts the flow rate by controlling the opening degree of the control valve, or switches the branch pipelines to change the injection point.

[0023] The pressure balance module is arranged along the horizontal well in sections, and includes a pressure relief pipeline and a pressure relief valve group, each section of the pressure relief pipeline corresponds to a specific stress area, and the opening, closing and pressure relief rate of the pipeline are controlled through the pressure relief valve to release the pressure of the high stress area.

[0024] The gas production execution module is connected with the gas production channel, and is composed of a gas production pipeline, a gas production regulating valve and a flow monitoring assembly, the gas production regulating valve adjusts the flow passage cross-sectional area of the pipeline according to the instructions to change the gas production rate, and the flow monitoring assembly monitors the flow rate in real time and feeds back the data.

[0025] Embodiment 1: The embodiment is applied to a horizontal well development project of a certain tight gas field, the reservoir of the gas field has the characteristics of low porosity and low permeability, and has strong stress sensitivity, and the conventional CO2 storage and gas production device is prone to CO2 channeling and reservoir pressure imbalance, which leads to the decrease of gas production efficiency and the decrease of storage safety. Based on this, the CO2 storage and gas production collaborative device suitable for the tight gas horizontal well of the application is adopted, as shown in Figure 1 and Figure 2 Through the collaborative work of the multiple modules, the real-time monitoring and accurate regulation of the reservoir state are realized, and the collaborative optimization goal of gas production and carbon storage is achieved.

[0026] In the device deployment phase, first complete the installation of the reservoir state perception module. The armored optical fiber is laid along the inner wall of the horizontal well bore in a circumferentially spaced manner, the armored optical fiber is wrapped with a corrosion-resistant and wear-resistant coating, the armored optical fiber is laid in an encrypted manner in the area where the reservoir permeability difference is greater than a preset value, a distributed optical fiber sensing unit is formed, and the distributed optical fiber sensing unit is used to collect reservoir temperature and strain data. At the same time, pressure sensors are installed in different permeable areas of the reservoir, and gas concentration sensors are installed in the gas collection channel to form a multi-parameter monitoring unit. The pressure sensor and the gas concentration sensor both adopt a waterproof sealing structure, the detection end of the pressure sensor faces the reservoir pore direction, the sampling port of the gas concentration sensor is connected with the reservoir through a filter screen, and the pore size of the filter screen is smaller than the average pore size of the reservoir, so that the collected data is accurate and the equipment is stable.

[0027] After the device is started, the reservoir state perception module starts to work. The distributed optical fiber sensing unit starts to continuously collect reservoir temperature and strain data; the multi-parameter monitoring unit starts synchronously, the pressure sensor collects reservoir pressure data in real time, the gas concentration sensor collects CO2 concentration data in the reservoir and the gas collection channel, and all collected data is transmitted to the intelligent analysis and control module in real time through a signal transmission line.

[0028] After receiving the data, the intelligent analysis and control module receives and pre-processes the temperature, strain, pressure and CO2 concentration data through the data receiving unit. Then the data is input into the model operation unit. In the implementation process of the embodiment, first, the measured values of the reservoir strain , the measured values of the reservoir pressure , and the measured values of the CO2 concentration are extracted from the data, and then the preset stable strain values of the reservoir , the original pressure of the reservoir , and the CO2 safe concentration threshold are retrieved.

[0029] According to the stress-concentration-seepage multi-field coupling model, the comprehensive state evaluation index of the reservoir is calculated, and the calculation formula is: , wherein, is the strain deviation, is the pressure deviation, is the CO2 concentration deviation, , , are the weight coefficients of strain, pressure and CO2 concentration on the reservoir state evaluation, respectively. The coefficients are obtained by the stress-strain relationship data under different confining pressures through the triaxial compression experiment of the reservoir core, and are determined by using the partial least squares regression algorithm combined with the CO2 storage and gas collection historical operation data of multiple groups of the same type of dense gas horizontal wells.

[0030] The model operation unit calculates a reservoir comprehensive state evaluation index Compared with a preset state threshold, if the reservoir comprehensive state evaluation index is less than the preset threshold, it is determined that the reservoir is in a stable state, and the current operating parameters of each module are maintained; if the reservoir comprehensive state evaluation index is greater than or equal to the preset threshold, it is determined that the reservoir is in an abnormal state, and further according to the strain deviation , the pressure deviation , and the CO2 concentration deviation , the parameter with the largest value is determined as the abnormal dominant factor.

[0031] The instruction generation unit generates control instructions according to the analysis results of the model operation unit. When the abnormal dominant factor is a too large strain deviation, control instructions for the pressure balance module are generated; when the abnormal dominant factor is a too large pressure deviation, control instructions for the pressure balance module and the gas production execution module are simultaneously generated; when the abnormal dominant factor is a too large CO2 concentration deviation, control instructions for the CO2 injection control module are generated, and the generated control instructions are transmitted to the corresponding modules.

[0032] After receiving the instructions, the CO2 injection control module determines the injection point and the corresponding injection parameters that need to be adjusted, locates the branch injection pipeline corresponding to the injection point and the control valve on the pipeline, adjusts the CO2 flow in the branch injection pipeline by controlling the opening degree of the control valve, realizes the adjustment of the injection state, and if it is necessary to switch the injection point, the control valve of the current branch injection pipeline is closed, and the control valve of the target branch injection pipeline is opened, to complete the switching of the injection point.

[0033] After receiving the instructions, the pressure balance module determines the high stress area that needs to be relieved according to the instructions, controls the relief valve on the relief pipeline corresponding to the area, adjusts the opening degree of the relief valve to control the relief rate, releases the pressure of the high stress area of the reservoir, and stops until the stress of the reservoir returns to the stable range.

[0034] After receiving the instructions, the gas production execution module adjusts the flow area of the gas production pipeline through the gas production regulating valve, and then adjusts the gas production rate, while the flow monitoring assembly monitors the gas flow in the gas production pipeline in real time and transmits the flow data to the intelligent analysis and control module to form a closed-loop control, ensuring that the gas production rate matches the reservoir state.

[0035] During the entire implementation process, the intelligent analysis and control module continuously receives the data transmitted by the reservoir state sensing module, and repeatedly performs the above analysis and control process until the reservoir comprehensive state evaluation index is less than the preset threshold, the reservoir returns to a stable state, and the current operating parameters of each module are maintained, realizing continuous and stable CO2 storage and tight gas production operations.

[0036] In summary, through the cooperative work of each module, the problems of single parameter regulation and the lack of consideration of stress sensitivity of the dense gas reservoir in the existing device are effectively solved. The reservoir state perception module realizes multi-dimensional data synchronous acquisition, providing accurate data support for regulation; the intelligent analysis and regulation module accurately judges the reservoir state through the multi-field coupling model, ensuring the accuracy of the regulation direction; the CO2 injection regulation module avoids CO2 channeling along the high stress fracture, and the pressure balance module and the gas production execution module cooperatively solve the problem of reservoir pressure imbalance, ultimately realizing the synchronous improvement of the dense gas horizontal well gas production efficiency and the safety of CO2 storage, ensuring the stable achievement of the energy development and carbon emission reduction collaborative goals, and providing a reliable technical solution for CO2 storage and gas production operation in similar dense gas fields.

[0037] Embodiment 2: This embodiment is applied to a certain dense gas horizontal well block with complex natural fractures. In addition to the characteristics of low porosity and low permeability, the complex CO2 channeling channels are caused by the development of natural fractures in the block, and the stress distribution in the fracture area is uneven. The conventional device is prone to storage failure due to the disordered migration of CO2 along the fracture, and the reservoir pressure fluctuates greatly, resulting in poor gas production stability. Based on this, the module deployment and regulation logic are optimized for the complex fracture reservoir characteristics based on the device of Embodiment 1, and the dynamic balance of CO2 accurate storage and dense gas efficient development is realized through the cooperation of multiple modules, as shown in Figure 1 and Figure 2 , the specific contents are as follows: In the device deployment stage, the optimization layout scheme is based on the reservoir state perception module of Embodiment 1. In addition to being laid along the inner wall of the horizontal wellbore in a circumferential interval, the distributed optical fiber sensing unit is additionally laid armored optical fiber along the fracture strike in the proven natural fracture development zone, and further densified in the fracture intersection area, to ensure comprehensive capture of temperature and strain changes in the fracture area. In the multi-parameter monitoring unit, the laying density of the pressure sensor and the gas concentration sensor in the fracture vicinity reservoir is increased, and a gas concentration sensor is additionally added on the side of the gas production channel near the fracture to monitor whether CO2 has channelled into the gas production channel through the fracture in real time. All sensors still maintain a waterproof sealed structure, and the pore size of the gas concentration sensor sampling port filter screen is maintained to be less than the average pore size of the reservoir.

[0038] After the device is started, the reservoir state perception module operates according to the optimized layout scheme, the distributed optical fiber sensing unit synchronously collects temperature and strain data of the wellbore and fracture area, and the multi-parameter monitoring unit collects reservoir pressure and CO2 concentration data in different areas. All data are transmitted to the intelligent analysis and regulation module in real time.

[0039] After receiving the data, the data receiving unit of the intelligent analysis and regulation module completes data preprocessing. In the implementation process of this embodiment, the model operation unit extracts the measured values of reservoir strain , pressure , CO2 concentration measured value , call the preset reservoir stable strain value , reservoir original pressure , CO2 safety concentration threshold .

[0040] According to the stress-concentration-seepage multi-field coupling model, the reservoir comprehensive state evaluation index is calculated , the calculation formula is: , Among them , , , , , The determination method is consistent with that of embodiment 1, but in the model operation, the strain and pressure data of the fracture area are additionally given higher weights, and the reservoir state of the fracture area is preferentially judged. When the reservoir comprehensive state evaluation index is greater than or equal to the preset threshold value, in addition to determining the abnormal dominant factor, the strain data of the fracture area captured by the distributed optical fiber sensing unit is further combined to locate whether the abnormality is from the fracture area.

[0041] The instruction generation unit generates targeted regulation instructions according to the analysis result. If the abnormal dominant factor is that the CO2 concentration deviation is too large and is located in the fracture area, instructions for adjusting the CO2 injection regulation module are generated, and the branch injection pipeline close to the abnormal fracture area is preferentially closed; if the abnormal dominant factor is that the strain deviation is too large and is from the high stress of the fracture area, the pressure balance module regulation instruction is generated, and the corresponding pressure relief pipeline near the fracture is opened; if the abnormal dominant factor is that the pressure deviation is too large, the regulation instructions of the pressure balance module and the gas production execution module are generated simultaneously, and the pressure relief rate and the gas production rate are adjusted.

[0042] After receiving the instructions, the CO2 injection regulation module adjusts the injection point and the injection flow according to the method of embodiment 1, and for the abnormal situation of the fracture area, if the branch injection pipeline close to the fracture needs to be closed and the branch injection pipeline in the stable reservoir state area away from the fracture needs to be opened, the continuous injection of CO2 to the fracture area is avoided; after receiving the instructions, the pressure balance module controls the pressure relief valve of the corresponding pressure relief pipeline to slowly open for the high stress condition of the fracture area, so as to avoid the further expansion of the fracture caused by the too fast pressure relief rate; after receiving the instructions, the gas production execution module adjusts the gas production rate through the gas production adjusting valve, and the flow monitoring assembly feedbacks the flow data in real time to form a closed-loop regulation. If it is found that CO2 has entered the gas production channel through the fracture, the gas production rate is appropriately reduced to give time for the pressure balance module to adjust the reservoir pressure.

[0043] During the entire implementation process, the intelligent analysis and regulation module continuously tracks the reservoir data of the fracture area, and when the reservoir comprehensive state evaluation index When the pressure drops below the preset threshold value and the strain, pressure and CO2 concentration of the crack region return to stable, the current control parameters are maintained to realize stable operation under the complex crack reservoir.

[0044] In summary, the embodiment optimizes the reservoir state sensing module layout scheme and adjusts the operation logic of the intelligent analysis and control module to solve the CO2 channeling and pressure imbalance problems in the complex crack reservoir. Compared with embodiment 1, the reservoir changes in the crack region are more accurately captured, the control instruction is more suitable for the characteristics of the complex crack reservoir, the CO2 channeling along the natural cracks leading to storage failure is effectively avoided, the reservoir pressure is stabilized, and the gas production efficiency is ensured. The embodiment provides a more adaptable technical solution for CO2 storage and gas production operation of the tight gas horizontal well with complex natural cracks, further expands the application range of the device of the present application.

[0045] The above is only a preferred embodiment of the present application, and does not limit the present application in any form. Although the present application has been disclosed as above with a preferred embodiment, it is not intended to limit the present application. Any person skilled in the art can make some changes or modifications to the above disclosed technical content to obtain equivalent embodiments with equivalent changes, without departing from the technical solution of the present application. Any modification, equivalent change and modification of the above embodiments made in accordance with the technical essence of the present application shall still fall within the scope of the technical solution of the present application.

Claims

1. A CO2 sequestration gas recovery synergic device adapted to a compact gas horizontal well, characterized by, The device comprises a reservoir state sensing module, an intelligent analysis and control module, a CO2 injection control module, a pressure balance module and a gas production execution module. The reservoir state sensing module is arranged along the horizontal well bore and key areas of the reservoir, and is used to collect reservoir temperature, strain, pressure and CO2 concentration data. The intelligent analysis and control module is connected with the reservoir state sensing module, the CO2 injection control module, the pressure balance module and the gas production execution module, and is provided with a stress-concentration-seepage multi-field coupling model, which is used to receive and analyze the data transmitted by the reservoir state sensing module, and generate control instructions. The CO2 injection control module is installed on the CO2 injection channel, and is used to adjust the CO2 injection point and injection state according to the instructions of the intelligent analysis and control module. The pressure balance module is arranged along the horizontal well, and is used to release the pressure of the high stress area of the reservoir according to the instructions of the intelligent analysis and control module. The gas production execution module is connected with the gas production channel of the horizontal well, and is used to adjust the gas production rate according to the instructions of the intelligent analysis and control module.

2. The CO2 sequestration gas recovery co-ordinated device for adapting a tight gas horizontal well of claim 1, wherein, The reservoir state sensing module comprises a distributed optical fiber sensing unit and a multi-parameter monitoring unit, and when collecting reservoir data, the following steps are included: The distributed optical fiber sensing unit is laid along the horizontal well bore and key areas of the reservoir, and the pressure sensor and the gas concentration sensor in the multi-parameter monitoring unit are installed in different permeable areas of the reservoir and the gas production channel respectively; The distributed optical fiber sensing unit is started to collect reservoir temperature and strain data; The multi-parameter monitoring unit is started synchronously to collect reservoir pressure data through the pressure sensor and CO2 concentration data in the reservoir and the gas production channel through the gas concentration sensor, and all the collected data are transmitted to the intelligent analysis and control module in real time.

3. The CO2 sequestration gas recovery co-ordinated device for adapting a tight gas horizontal well of claim 2, wherein, The distributed optical fiber sensing unit adopts armored optical fiber, the outer layer of which is wrapped with a corrosion-resistant and wear-resistant coating, and the armored optical fiber is laid along the inner wall of the horizontal well bore in a circumferential interval, and is laid in an encrypted manner in the area where the reservoir permeability difference is greater than a preset value.

4. The CO2 sequestration gas recovery co-ordinated device for adapting a tight gas horizontal well of claim 2, wherein, The pressure sensor and the gas concentration sensor in the multi-parameter monitoring unit both adopt a waterproof sealing structure, the detection end of the pressure sensor is arranged towards the reservoir pore direction, the sampling port of the gas concentration sensor is communicated with the reservoir through a filter screen, and the pore size of the filter screen is smaller than the average pore size of the reservoir.

5. The CO2 sequestration gas recovery synergetic device for adapting tight gas horizontal well of claim 1, wherein, The intelligent analysis and control module comprises a data receiving unit, a model operation unit and an instruction generating unit, and when processing data and generating control instructions, the following steps are included: The temperature, strain, pressure and CO2 concentration data transmitted by the reservoir state sensing module are received by the data receiving unit; The received data are input into the model operation unit, the measured values of the reservoir strain, the measured values of the pressure and the measured values of the CO2 concentration are extracted first, the preset stable strain value of the reservoir, the original pressure of the reservoir and the CO2 safety concentration threshold value are retrieved, the stress-concentration-seepage multi-field coupling model is used to calculate the reservoir comprehensive state evaluation index, and the stress stability of the reservoir, the CO2 migration trend and the pressure balance state are judged according to the numerical value of the reservoir comprehensive state evaluation index. The instruction generating unit generates control instructions for the CO2 injection control module, the pressure balance module and the gas production execution module respectively according to the analysis result of the model calculation unit; The generated control instructions are transmitted to the corresponding CO2 injection control module, pressure balance module and gas production execution module.

6. The CO2 sequestration gas recovery co-ordinated device for adapting a tight gas horizontal well of claim 5, wherein, When the model calculation unit performs calculation analysis, the calculated reservoir comprehensive state evaluation index is compared with a preset state threshold value; when the reservoir comprehensive state evaluation index is less than the preset threshold value, it is determined that the reservoir is in a stable state; when the reservoir comprehensive state evaluation index is greater than or equal to the preset threshold value, it is determined that the reservoir is in an abnormal state, and the abnormal dominant factor is further determined according to the parameter with the largest value among the strain deviation, pressure deviation and CO2 concentration deviation.

7. The CO2 sequestration gas recovery synergetic device for adapting tight gas horizontal well of claim 1, wherein, The CO2 injection control module includes an injection main pipeline, branch injection pipelines and an injection control valve group, and when adjusting the CO2 injection point and injection state, the CO2 injection control module includes the following steps: Receiving the control instructions transmitted by the intelligent analysis and control module, determining the injection point that needs to be adjusted and the corresponding injection parameters; According to the determined injection point, positioning the corresponding branch injection pipeline and the control valve on the branch injection pipeline; Controlling the opening degree of the corresponding control valve to adjust the CO2 flow in the branch injection pipeline and realize the adjustment of the injection state; When the injection point needs to be switched, the control valve of the current branch injection pipeline is closed, and the control valve of the target branch injection pipeline is opened to complete the injection point switching.

8. The CO2 sequestration gas recovery synergetic device for adapting tight gas horizontal well of claim 1, wherein, The pressure balance module includes a pressure relief pipeline and a pressure relief valve group, the pressure relief pipeline is arranged in sections along the length direction of the horizontal well, each section of the pressure relief pipeline corresponds to a specific stress area of the reservoir, one end of each section of the pressure relief pipeline extends to the corresponding area of the reservoir, and the other end is connected with an external pressure relief system, the pressure relief valve group includes a plurality of pressure relief valves, each pressure relief valve is installed on a section of the pressure relief pipeline, and each pressure relief valve is signal connected with the intelligent analysis and control module for controlling the opening, closing and pressure relief rate of the corresponding pressure relief pipeline according to the control instructions.

9. The CO2 sequestration gas recovery synergetic device for adapting tight gas horizontal well of claim 1, wherein, The gas production execution module includes a gas production pipeline, a gas production regulating valve and a flow monitoring assembly, the gas production pipeline is in communication with the gas production channel of the horizontal well and is used for conveying the produced tight gas, the gas production regulating valve is installed on the gas production pipeline and is signal connected with the intelligent analysis and control module for adjusting the flow area of the gas production pipeline and further adjusting the gas production rate according to the control instructions, and the flow monitoring assembly is installed on the gas production pipeline downstream of the gas production regulating valve and is used for monitoring the gas flow in the gas production pipeline and transmitting the flow data to the intelligent analysis and control module.

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