Method and device for optimizing vertical heating interval of electrical heating well pattern of shale rich in organic matters

Abstract

The invention discloses a method and device for optimizing the vertical heating layer distance of an organic matter-rich shale electric heating well pattern. The method comprises the steps that according to a designed heating well pattern unit, an experimental heating well pattern unit is obtained through equal-proportion reduction; obtaining an experimental data set obtained by performing a thermal simulation experiment by using the shale sample, each group of data in the experimental data set comprising a heating time and a plurality of data pairs, and each data pair comprising a distance between a selected heat source and a temperature sensor and a corresponding test temperature; respectively converting the heating time and distance in the experimental data set according to the scaling; according to the converted data set, establishing a corresponding relation among the actual conversion time, the actual distance and the formation temperature; and according to the minimum kerogen conversion temperature and the optimal heating time of the shale, the vertical heating interval is optimized by utilizing the corresponding relation. According to the method, reasonable optimization of the vertical heating layer distance of the organic matter-rich shale electric heating well pattern can be achieved.

Description

Technical Field

[0001] The invention relates to the technical field of shale oil development, and in particular to a method and device for optimizing the vertical heating layer spacing of an organic-rich shale electric heating well pattern. Background Art

[0002] The existing well network deployment is mainly aimed at the development of underground oil and gas reservoirs, mainly including the development of conventional conglomerate oil and gas reservoirs, tight conglomerate oil and gas reservoirs and shale oil and gas reservoirs. The well network deployment forms mainly include inverted nine-point, five-point, linear, four-point and seven-point injection and production well networks. Most of the existing well network deployment methods are based on development parameters such as effective half-fracture length, horizontal section length, fracturing section spacing, number of perforation clusters per section and expected mining life. The oil and gas wells and water injection wells are evenly deployed, and the well spacing is relatively large, generally several hundred meters.

[0003] The existing methods for in-situ well network deployment for oil shale mining target the solid organic matter in the shallowly buried oil shale. Usually, a row of injection wells is deployed above the oil shale layer to heat it by injecting high-temperature fluid, and a row of production wells with the same number are deployed below to extract oil and gas. These methods are suitable for in-situ mining of thin layers of oil shale with a burial depth of less than 300 meters, but not for in-situ mining of thick layers of organic-rich shale with a burial depth of more than 1,000 meters. The physical properties of deeply buried shale reservoirs are very poor, and it is difficult to inject high-temperature fluids and achieve uniform heating. Summary of the invention

[0004] In order to enrich the process routes and increase the selection space, the embodiments of the present invention provide a method and device for optimizing the vertical heating layer spacing of the organic-rich shale electric heating well network, which can realize the reasonable optimization of the vertical heating layer spacing of the organic-rich shale electric heating well network.

[0005] In a first aspect, an embodiment of the present invention provides a method for optimizing the vertical heating layer spacing of an organic-rich shale electric heating well pattern, comprising:

[0006] According to the designed heating well pattern unit, the scaling ratio is determined in combination with the set experimental heat source distance, and the experimental heating well pattern unit is obtained by scaling down in proportion;

[0007] Acquire an experimental data set obtained by conducting a thermal simulation experiment using a shale sample, wherein a heat source group deployed according to the experimental heating well pattern unit is deployed in the sample, and a plurality of temperature sensors are deployed between two heat sources in a vertical direction, and each set of data in the experimental data set includes a heating time and a plurality of data pairs, and each data pair includes a distance between a selected heat source and a temperature sensor and a corresponding test temperature;

[0008] According to the scaling ratio, the heating time and distance in the experimental data set are converted into the actual conversion time and the actual distance in the actual conversion process, respectively, and the test temperature is used as the formation temperature to obtain a converted data set;

[0009] The converted data set is used to establish the corresponding relationship between the actual conversion time, actual distance and formation temperature;

[0010] According to the minimum kerogen conversion temperature and the optimal heating time of the shale, the optimal vertical heating layer distance of the shale electric heating well network is determined using the corresponding relationship.

[0011] In a second aspect, an embodiment of the present invention provides a method for deploying an organic-rich shale electric heating well network, characterized by comprising:

[0012] In the process of deploying the shale electric heating well network, the heating wells are deployed according to the vertical heating layer spacing determined by the above method.

[0013] In a third aspect, an embodiment of the present invention provides a device for optimizing the vertical heating layer spacing of an organic-rich shale electric heating well pattern, comprising:

[0014] The experimental heating well network unit design module is used to design the heating well network unit and determine the scaling ratio in combination with the set experimental heat source distance, and obtain the experimental heating well network unit by scaling down in proportion;

[0015] An experimental data set acquisition module is used to acquire an experimental data set obtained by performing a thermal simulation experiment using a shale sample, wherein a heat source group deployed according to the experimental heating well pattern unit is deployed in the sample, and a plurality of temperature sensors are deployed between two heat sources in a vertical direction, and each group of data in the experimental data set includes a heating time and a plurality of data pairs, and each data pair includes a distance between a selected heat source and a temperature sensor and a corresponding test temperature;

[0016] An experimental data set conversion module, for converting the heating time and distance in the experimental data set into actual conversion time and actual distance in an actual conversion process according to the scaling ratio, and taking the test temperature as the formation temperature to obtain a converted data set;

[0017] A corresponding relationship establishment module, used to establish a corresponding relationship between actual conversion time, actual distance and formation temperature using the converted data set;

[0018] The vertical heating layer spacing optimization module is used to determine the optimal vertical heating layer spacing of the shale electric heating well network based on the minimum kerogen conversion temperature and the optimal heating time of the shale using the corresponding relationship.

[0019] In a fourth aspect, an embodiment of the present invention provides a computer storage medium, wherein the computer storage medium stores computer executable instructions, and when the computer executable instructions are executed by a processor, the method for optimizing the vertical heating layer spacing of the organic-rich shale electric heating well network is implemented.

[0020] The beneficial effects of the above technical solution provided by the embodiment of the present invention include at least:

[0021] The method for optimizing the vertical heating layer distance of the electric heating well pattern for organic-rich shale provided in the embodiment of the present invention simulates the real heating well pattern unit through a proportionally reduced experimental method, obtains multiple sets of data through thermal simulation experiments, each set of data contains different heating times and corresponding monitoring temperatures and the distance of the temperature measuring point from the selected heat source, performs real time and space conversion on the data, and finally establishes the corresponding relationship between the actual conversion time, the actual distance and the formation temperature through fitting; calculates the optimal vertical heating layer distance according to the minimum conversion temperature and optimal heating time of the kerogen of the shale in the study area. The reasonable optimization of the vertical heating layer distance of the in-situ electric heating well pattern for organic-rich shale is achieved, which reduces production costs and improves production efficiency.

[0022] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0023] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0025] Figure 1 This is a flow chart of a method for optimizing vertical heating layer spacing of an organic-rich shale electric heating well pattern in Example 1 of the present invention;

[0026] Figure 2 It is a schematic diagram of the sample and the experimental heating well pattern unit in Example 1 of the present invention;

[0027] Figure 3 A single well cross-sectional diagram for determining the thickness of the target layer for shale in-situ heating in Example 2 of the present invention;

[0028] Figure 4 This is a schematic diagram of a heating well pattern unit in Embodiment 2 of the present invention;

[0029] Figure 5This is a schematic diagram of the deployment of the experimental heating well pattern unit and the temperature sensor in the second embodiment of the present invention;

[0030] Figure 6 is a cross-plot of the actual distance and the test temperature corresponding to each heating time in the second embodiment of the present invention;

[0031] Figure 7 are cross-plots of heating time and coefficients a and b in Example 2 of the present invention;

[0032] Figure 8 A schematic diagram of the structure of a device for optimizing the vertical heating layer spacing of an organic-rich shale electric heating well pattern in an embodiment of the present invention. DETAILED DESCRIPTION

[0033] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0034] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0035] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the art to which the invention belongs. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0036] In order to solve the problem that the prior art method for in-situ mining of oil shale well network deployment is not suitable for in-situ mining of thick organic-rich shale with a burial depth of more than 1000 meters, an embodiment of the present invention provides a method and device for optimizing the vertical heating layer spacing of an organic-rich shale electric heating well network, focusing on solving the problem of optimizing the vertical heating layer spacing of an organic-rich shale in-situ electric heating well network.

[0037] Embodiment 1

[0038] Embodiment 1 of the present invention provides a method for optimizing the vertical heating layer spacing of an organic-rich shale electric heating well pattern, and the process thereof is as follows: Figure 1 As shown, the following steps are included:

[0039] Step S11: Determine the scaling ratio based on the designed heating well network unit and the set experimental heat source distance, and obtain the experimental heating well network unit by scaling it down in proportion.

[0040] According to the thickness of the in-situ heating target layer in the study area, the structure of the three-dimensional heating well network unit is designed, usually a triangular well network unit consisting of 3 heating wells, a quadrilateral well network unit consisting of 4 heating wells, or a hexagonal well network consisting of 6 heating wells. The vertical heating layer distance is set, that is, the initial vertical heating layer distance is generally 2 to 15 meters, and the horizontal heating well distance is 5 to 20 meters.

[0041] According to the heating well network unit structure, the vertical heating layer spacing and horizontal heating well spacing are set to determine the designed heating well network unit.

[0042] The experimental heat source distance can be the horizontal distance between the experimental heat sources or the vertical distance between the experimental heat sources. Generally, the horizontal distance between the experimental heat sources is 0.2 to 1 meter.

[0043] For example, the reduction ratio is determined based on the actual designed heating well pattern unit size and the horizontal distance between the experimental heat source, which is generally reduced to 0.05-0.1 of the actual size. The experimental well pattern unit is obtained by proportionally reducing the vertical and horizontal dimensions, thereby determining the location of the heating source.

[0044] Step S12: Acquire an experimental data set obtained by performing a thermal simulation experiment using a shale sample.

[0045] The heating wells in the designed heating well network unit are multiple horizontal wells deployed in parallel. The size of the sample is determined according to the size of the designed heating well network unit.

[0046] For details, see Figure 2 As shown, the shape of the sample is a cuboid, and the width of the sample is the width of the side parallel to the heat source. The length of the sample is greater than 2 times the length of the experimental heating well network unit, the height of the sample is greater than 2 times the height of the experimental heating well network unit, and the width of the sample is not less than the set experimental heat source distance. Figure 2 The red lines in the diagram indicate heat sources.

[0047] A heat source group is deployed in the sample according to the experimental heating well network unit, and multiple temperature sensors are deployed between two heat sources in the vertical direction.

[0048] Furthermore, multiple temperature sensors are arranged at equal intervals between the center of the heat source group and the selected heat source, the selected heat source and the center of the heat source group are on the same vertical line, and the number of temperature sensors is at least 6.

[0049] The thermal simulation experiment process is as follows:

[0050] (1) Heat the sample to 270°C using a heat source at a first heating rate.

[0051] The first heating rate is relatively fast, usually 50-100°C / day, and generally requires rapid heating for 3-5 days.

[0052] (2) Heat the sample to 600°C using a heat source at a second heating rate and keep the temperature constant.

[0053] The second heating rate is slower, usually 10-30°C / day.

[0054] After slowly heating the sample to a temperature of 600°C, the heating power is adjusted so that the temperature of the heat source does not change, and constant heating at 600°C is performed.

[0055] The constant temperature heating time is determined according to the distance between the heat sources. The closer the distance between the heat sources, the shorter the heating time. When the distance between the heat sources is within 0.5 meters, the heating time is generally 2 to 3 months; when the distance between the heat sources is within 0.5 to 1 meter, the heating time is generally 4 to 6 months.

[0056] (3) Collect data from each temperature sensor at set time intervals to obtain an experimental data set.

[0057] At least 6 groups of data are collected during the constant temperature heating cycle. Furthermore, the interval for data collection is usually set to 10 to 30 days.

[0058] Each set of data in the obtained experimental data set includes a heating time and multiple pairs of data, and each pair of data includes the distance between the selected heat source and the temperature sensor and the corresponding test temperature.

[0059] It is further understood that the experimental data set includes at least 6 groups of data, and each group of data includes at least 6 data pairs.

[0060] The above-mentioned experimental samples can be real rock samples collected from surface outcrops or target layers near the surface.

[0061] The samples are wrapped with thermal insulation materials to prevent heat loss and simulate the heating environment of the formation as much as possible.

[0062] Step S13: According to the scaling ratio, the heating time and distance in the experimental data set are converted into the actual conversion time and actual distance in the actual conversion process, and the test temperature is used as the formation temperature to obtain the converted data set.

[0063] The heating time in the experimental data set is converted into the actual conversion time in the actual conversion process according to formula (1):

[0064] ta=te / R(1)

[0065] In formula (1), ta is the actual conversion time, te is the experimental heating time, and R is the scaling ratio from the designed heating well pattern unit to the experimental heating well pattern unit.

[0066] The distance in the experimental data set is converted into the actual distance in the actual conversion process according to formula (2):

[0067] La=Le / R(2)

[0068] In formula (2), La is the actual distance obtained by conversion, and Le is the distance between the selected heat source and the temperature sensor in the rock sample.

[0069] The above time units are days and distance units are meters.

[0070] Step S14: using the converted data set to establish a corresponding relationship between the actual conversion time, the actual distance and the formation temperature.

[0071] For each actual conversion time, according to the corresponding multiple pairs of data including actual distance and formation temperature, the first fitting relationship between the actual distance and formation temperature is obtained by fitting:

[0072] La=a*T b (3)

[0073] In formula (3), La is the actual distance obtained by conversion, T is the formation temperature, and a and b are coefficients determined by fitting.

[0074] According to each actual conversion time and its corresponding coefficients a and b, the relationship between the actual conversion time ta and the coefficient a and the relationship between the actual conversion time ta and the coefficient b are fitted respectively:

[0075] a=a1*e a2*ta (4)

[0076] b=b1*ta+b2(5)

[0077] In equations (4) and (5), ta is the actual conversion time, and a1, a2, b1 and b2 are coefficients determined by fitting.

[0078] Substitute the coefficients a1, a2, b1 and b2 determined by fitting into the above formula (3) to establish the corresponding relationship between the actual conversion time, actual distance and formation temperature:

[0079] La=(a1*e a2*ta )*T (b1*ta+b2) (6).

[0080] Step S15: According to the minimum kerogen conversion temperature and the optimal heating time of the shale, the optimal vertical heating layer distance of the shale electric heating well network is determined by using the corresponding relationship.

[0081] According to the correspondence between the actual conversion time, actual distance and formation temperature, the correspondence between the vertical heating layer distance, formation temperature and actual conversion time is obtained:

[0082] L = 2*(a1*e a2*ta )*T (b1*ta+b2) (7)

[0083] In formula (7), L is the vertical heating layer distance.

[0084] According to the minimum conversion temperature of kerogen and the optimal heating time of shale, the optimal vertical heating layer distance of shale electric heating well pattern is determined using formula (7).

[0085] The minimum conversion temperature of kerogen can be determined by physical simulation of in-situ conversion of shale in the study area, and the optimal heating time can be determined by economic evaluation research in the study area.

[0086] The method for optimizing the vertical heating layer distance of the electric heating well network of organic-rich shale provided in the first embodiment of the present invention simulates the real heating well network unit through the experimental method of proportional reduction, obtains multiple groups of data through the thermal simulation experiment, each group of data contains different heating times and corresponding monitoring temperatures and the distance of the temperature measuring point from the selected heat source, performs real time and space conversion on the data, and finally establishes the corresponding relationship between the actual conversion time, the actual distance and the formation temperature through fitting; according to the minimum conversion temperature and optimal heating time of the kerogen of the shale in the study area, the optimal vertical heating layer distance is calculated. The reasonable optimization of the vertical heating layer distance of the in-situ electric heating well network of organic-rich shale is achieved, which reduces the production cost and improves the production efficiency.

[0087] Embodiment 2

[0088] Embodiment 2 of the present invention provides a specific application of a method for optimizing the vertical heating layer spacing of an organic-rich shale electric heating well pattern, comprising the following steps:

[0089] 1. Obtain parameters such as TOC, S1, S2, etc. that characterize the heated geological body in the study area, and determine that the thickness of the heating target layer in the embodiment is 20 meters.

[0090] See also Figure 3 As shown, this is a single well profile diagram for determining the thickness of the target layer for shale in-situ heating.

[0091] 2. The designed heating well network unit is a quadrilateral consisting of 4 wells, with an initial vertical heating layer spacing of 3 meters and a horizontal heating well spacing of 6 meters.

[0092] See also Figure 4shown.

[0093] 3. The reduction ratio is 0.1. The vertical spacing of the heat sources in the experimental well network is 0.3 meters. Six temperature sensors are arranged at intervals of 0.05 meters from the center of the heating well network unit to the heat sources in the vertical direction.

[0094] See also Figure 5 shown.

[0095] 4. The dimensions of the prepared sample are 1.2 meters in length and height and 0.6 meters in width.

[0096] 5. Heating procedure: The heat source is first quickly heated to 270°C for 3 days, and then slowly heated up, generally 30°C / day. When the temperature is heated to 600°C, the heating power is adjusted so that the heat source temperature does not change, and the constant temperature of 600°C is heated. The heating time is 162 days.

[0097] 6. Experimental data collection: Each temperature sensor collects temperature data once every 18 days, and the data is collected 9 times in total during the 162-day heating period (Table 1).

[0098] Table 1 Experimental measurements of temperatures at different locations from the heat source at different heating times

[0099]

[0100] 7. Data processing: R is 0.1. According to formulas (1) and (2), the geological extrapolation of the heating time and the distance of the temperature measurement point from the selected heat source is performed (Table 2, Table 3).

[0101] Table 2 Geological extrapolation results of heating time

[0102]

[0103] Table 3 Geological extrapolation results of the distance between the temperature measurement point and the selected heat source

[0104]

[0105] 8. Establishment of vertical heating layer distance optimization model:

[0106] 8.1 Make a cross plot of the test temperature and the distance of the temperature measurement point from the selected heat source after geological extrapolation ( Figure 6 ), and the power function model was used to calculate the model coefficients a and b under different heating time conditions (Table 4).

[0107] Table 4 Coefficients a and b for different heating times

[0108] ta(day) 180 360 540 720 900 1080 1260 1440 1620 a 224147 4.00E+07 2.00E+12 6.00E+15 3.00E+18 3.00E+20 1.00E+22 1.00E+24 1.00E+27 b -2.329 -3.168 -4.977 -6.27 -7.234 -8.009 -8.558 -9.323 -10.39

[0109] 8.2 Based on the calculated coefficients a and b of different heating times and the heating time data after geological extrapolation, make a cross plot ( Figure 7 ), calculate the model coefficients a1=4724.9, a2=0.0341, b1=-0.0055, b2=-1.7278.

[0110] 8.3 Based on the coefficients a1, a2, b1, and b2 determined in 8.2, the following heating well spacing optimization model applicable to the study area is established:

[0111] L=4724.9*e 0.0341ta *T (-0.0055*ta-1.7278) (8)

[0112] 9. The lowest kerogen conversion temperature determined by the in-situ conversion physical simulation experiment in the study area is 330 degrees, the optimal heating time determined by the economic evaluation study is 4 years, and the optimal vertical heating layer distance is calculated to be 5.26 meters.

[0113] Based on the inventive concept of the present invention, an embodiment of the present invention also provides a method for deploying an organic-rich shale electric heating well network. In the process of deploying the shale electric heating well network, the heating wells are deployed according to the vertical heating layer spacing determined by the above method.

[0114] Based on the inventive concept of the present invention, the embodiment of the present invention also provides a device for optimizing the vertical heating layer distance of an organic-rich shale electric heating well pattern. The structure of the device is as follows: Figure 8 As shown, including:

[0115] The experimental heating well pattern unit design module 81 is used to design the heating well pattern unit and determine the scaling ratio in combination with the set experimental heat source distance, and obtain the experimental heating well pattern unit by scaling down in proportion;

[0116] The experimental data set acquisition module 82 is used to acquire an experimental data set obtained by performing a thermal simulation experiment using a shale sample, wherein the sample is deployed with a heat source group deployed according to the experimental heating well pattern unit, and a plurality of temperature sensors are deployed between two heat sources in a vertical direction, and each group of data in the experimental data set includes a heating time and a plurality of data pairs, and each data pair includes a distance between a selected heat source and a temperature sensor and a corresponding test temperature;

[0117] An experimental data set conversion module 83 is used to convert the heating time and distance in the experimental data set into actual conversion time and actual distance in an actual conversion process according to the scaling ratio, and use the test temperature as the formation temperature to obtain a converted data set;

[0118] A corresponding relationship establishing module 84, for establishing a corresponding relationship between the actual conversion time, the actual distance and the formation temperature using the converted data set;

[0119] The vertical heating layer spacing optimization module 85 is used to determine the optimal vertical heating layer spacing of the shale electric heating well network based on the minimum kerogen conversion temperature and the optimal heating time of the shale using the corresponding relationship.

[0120] Regarding the device in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0121] Based on the inventive concept of the present invention, an embodiment of the present invention also provides a computer storage medium, in which computer executable instructions are stored. When the computer executable instructions are executed by a processor, the above-mentioned method for optimizing the vertical heating layer spacing of the organic-rich shale electric heating well network is implemented.

[0122] Unless otherwise specifically stated, terms such as processing, computing, calculating, determining, displaying, etc. may refer to the actions and / or processes of one or more processing or computing systems, or similar devices, which operate and convert data represented as physical (e.g., electronic) quantities within registers or memories of a processing system into other data similarly represented as physical quantities within memories, registers, or other such information storage, transmission, or display devices of the processing system. Information and signals may be represented using any of a variety of different techniques and methods. For example, data, instructions, commands, information, signals, bits, symbols, and chips mentioned throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, light fields or particles, or any combination thereof.

[0123] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of protection of the present disclosure. The attached method claims present the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0124] In the above detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that an embodiment of the claimed subject matter requires more features than those set forth in each claim. On the contrary, as reflected in the appended claims, the invention is in a state of having less than all the features of the disclosed individual embodiments. Therefore, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0125] Those skilled in the art will also appreciate that the various illustrative logic blocks, modules, circuits, and algorithmic steps described in conjunction with the embodiments herein can all be implemented as electronic hardware, computer software, or a combination thereof. In order to clearly illustrate the interchangeability between hardware and software, various illustrative components, blocks, modules, circuits, and steps are generally described above around their functions. Whether such functions are implemented as hardware or software depends on specific applications and the design constraints imposed on the entire system. A skilled person can implement the described functions in an alternative manner for each specific application, but such implementation decisions should not be interpreted as departing from the scope of protection of the present disclosure.

[0126] The steps of the method or algorithm described in conjunction with the embodiments herein may be directly embodied as hardware, a software module executed by a processor, or a combination thereof. The software module may be located in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a mobile disk, a CD-ROM, or any other form of storage medium well known in the art. An exemplary storage medium is connected to the processor so that the processor can read information from the storage medium and can write information to the storage medium. Of course, the storage medium may also be an integral part of the processor. The processor and the storage medium may be located in an ASIC. The ASIC may be located in a user terminal. Of course, the processor and the storage medium may also be present in a user terminal as discrete components.

[0127] For software implementation, the techniques described in this application can be implemented with modules (e.g., procedures, functions, etc.) that perform the functions described in this application. These software codes can be stored in a memory unit and executed by a processor. The memory unit can be implemented within the processor or outside the processor. In the latter case, it is coupled to the processor in a communication manner via various means, which are well known in the art.

[0128] The above description includes examples of one or more embodiments. Of course, it is impossible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it should be recognized by those skilled in the art that the various embodiments can be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is covered in a manner similar to the term "including", just as "including," explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to represent "non-exclusive or". The terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance.

Claims

1. A method for optimizing the vertical heating layer spacing of an organic-rich shale electric heating well pattern, characterized in that: include: According to the designed heating well pattern unit, the scaling ratio is determined in combination with the set experimental heat source distance, and the experimental heating well pattern unit is obtained by scaling down in proportion; Acquire an experimental data set obtained by conducting a thermal simulation experiment using a shale sample, wherein a heat source group deployed according to the experimental heating well pattern unit is deployed in the sample, and a plurality of temperature sensors are deployed between two heat sources in a vertical direction, and each set of data in the experimental data set includes a heating time and a plurality of data pairs, and each data pair includes a distance between a selected heat source and a temperature sensor and a corresponding test temperature; According to the scaling ratio, the heating time and distance in the experimental data set are converted into the actual conversion time and the actual distance in the actual conversion process, respectively, and the test temperature is used as the formation temperature to obtain a converted data set; The converted data set is used to establish the corresponding relationship between the actual conversion time, actual distance and formation temperature; According to the minimum kerogen conversion temperature and the optimal heating time of the shale, the optimal vertical heating layer distance of the shale electric heating well network is determined using the corresponding relationship.

2. The method according to claim 1, characterized in that The designed heating well pattern unit is obtained through the following steps: According to the heating well network unit structure, the vertical heating layer spacing and horizontal heating well spacing are set to determine the designed heating well network unit.

3. The method according to claim 2, characterized in that The heating well pattern unit structure is a triangular well pattern unit composed of three heating wells, a quadrilateral well pattern unit composed of four heating wells, or a hexagonal well pattern unit composed of six heating wells; The vertical heating layer distance is set to 2 to 15 meters, and the horizontal heating well distance is set to 5 to 20 meters.

4. The method according to claim 3, characterized in that The set experimental heat source distance is the horizontal distance of the experimental heat source, which is 0.2 to 1 meter.

5. The method according to claim 1, characterized in that The heating wells in the designed heating well pattern unit are multiple horizontal wells deployed in parallel; The shape of the sample is a cuboid, and the width of the sample is the width of the side parallel to the heat source; The length of the sample is greater than 2 times the length of the experimental heating well network unit, the height of the sample is greater than 2 times the height of the set experimental heating well network unit, and the width of the sample is not less than the set experimental heat source distance.

6. The method according to claim 1, characterized in that The experimental data set is obtained in the following way: heating the sample to 270° C. using the heat source at a first heating rate; At a second heating rate, heating the sample to 600° C. using the heat source, and maintaining the temperature constant; The data of each temperature sensor is collected at set intervals to obtain the experimental data set.

7. The method according to claim 6, characterized in that The first heating rate is 50-100°C / day, and the second heating rate is 10-30°C / day; The setting interval is 10 to 30 days.

8. The method according to claim 1, characterized in that The plurality of temperature sensors are arranged at equal intervals between the center of the heat source group and the selected heat source, and the selected heat source is on the same vertical line as the center; The number of temperature sensors is at least 6.

9. The method according to claim 1, characterized in that The step of converting the heating time and distance in the experimental data set into actual conversion time and actual distance in the actual conversion process comprises: The heating time in the experimental data set is converted into the actual conversion time in the actual conversion process according to formula (1): ta=te / R (1) In formula (1), ta is the actual conversion time, te is the experimental heating time, and R is the scaling ratio of the designed heating well pattern unit to the experimental heating well pattern unit; The distance in the experimental data set is converted into the actual distance in the actual conversion process according to formula (2): La=Le / R (2) In formula (2), La is the actual distance obtained by conversion, and Le is the distance between the selected heat source and the temperature sensor in the rock sample.

10. The method according to claim 1, characterized in that The using the converted data set to establish a corresponding relationship between the actual conversion time, the actual distance and the formation temperature includes: For each actual conversion time, according to the corresponding multiple pairs of data including actual distance and formation temperature, the first fitting relationship between the actual distance and formation temperature is obtained by fitting: La*T b (3) In formula (3), La is the actual distance obtained by conversion, T is the formation temperature, and a and b are coefficients determined by fitting; According to each actual conversion time and its corresponding coefficients a and b, the relationship between the actual conversion time ta and the coefficient a and the relationship between the actual conversion time ta and the coefficient b are fitted respectively: a=a1*e a2*ta (4) b=b1*ta+b2 (5) In formulas (4) and (5), ta is the actual conversion time, and a1, a2, b1, and b2 are coefficients determined by fitting; According to the coefficients a1, a2, b1 and b2 determined by fitting, the corresponding relationship between the actual conversion time, actual distance and formation temperature is established: At=(a1*e a2*ta )*T (b1*ta+b2) (6)。 11. The method according to claim 10, characterized in that The method of determining the optimal vertical heating layer distance of the shale electric heating well pattern according to the minimum kerogen conversion temperature and the optimal heating time of the shale using the corresponding relationship includes: According to the corresponding relationship, the corresponding relationship between the vertical heating layer distance, the formation temperature and the actual conversion time is obtained: L= (a1*e a2*ta )*T (b1*ta+b2) (7) In formula (7), L is the vertical heating layer distance; According to the minimum conversion temperature of kerogen and the optimal heating time of shale, the optimal vertical heating layer distance of shale electric heating well pattern is determined using formula (7).

12. A method for laying out an electric heating well network for organic-rich shale, characterized in that: include: In the process of deploying the shale electric heating well network, the heating wells are deployed according to the vertical heating layer spacing determined by any one of the methods described in claims 1 to 11.

13. An optimization device for vertical heating layer spacing of organic-rich shale electric heating well pattern, characterized in that: include: The experimental heating well network unit design module is used to design the heating well network unit and determine the scaling ratio in combination with the set experimental heat source distance, and obtain the experimental heating well network unit by scaling down in proportion; An experimental data set acquisition module is used to acquire an experimental data set obtained by performing a thermal simulation experiment using a shale sample, wherein a heat source group deployed according to the experimental heating well pattern unit is deployed in the sample, and a plurality of temperature sensors are deployed between two heat sources in a vertical direction, and each group of data in the experimental data set includes a heating time and a plurality of data pairs, and each data pair includes a distance between a selected heat source and a temperature sensor and a corresponding test temperature; An experimental data set conversion module, for converting the heating time and distance in the experimental data set into actual conversion time and actual distance in an actual conversion process according to the scaling ratio, and taking the test temperature as the formation temperature to obtain a converted data set; A corresponding relationship establishment module, used to establish a corresponding relationship between actual conversion time, actual distance and formation temperature using the converted data set; The vertical heating layer spacing optimization module is used to determine the optimal vertical heating layer spacing of the shale electric heating well network based on the minimum kerogen conversion temperature and the optimal heating time of the shale using the corresponding relationship.

14. A computer storage medium, characterized in that: The computer storage medium stores computer executable instructions, which, when executed by a processor, implement the method for optimizing the vertical heating layer spacing of an organic-rich shale electric heating well pattern as described in any one of claims 1 to 11.

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