Competitive exploitation gas reservoir gas exploitation speed optimization method and device

Abstract

The invention relates to the technical field of petroleum and natural gas exploration and development, in particular to a competitive exploitation gas reservoir gas exploitation speed optimization method and device. The method comprises the following steps: acquiring residual geological reserves of a gas reservoir before production in a first work area; the first work area is a square work area; determining a first development index of a first work area based on the residual geological reserves, and predicting a second development index of a second work area; the second work area is a non-partner work area; establishing a gas reservoir numerical model to predict a first development result at the end of the first work area when the first work area is developed under the first development index and the second work area is developed under the second development index at the same time; and optimizing the initial gas production speed of the first work area based on the first development result. On the basis of the method, the mining speed can be scientifically set, so that the development risk of the first work area is reduced, and benefit maximization is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of oil and natural gas exploration and development, and in particular to a method and device for optimizing gas production speed in competitive gas reservoir production. Background Art

[0002] With the increasingly frequent transfer of mining rights, different blocks of the same underground gas reservoir may belong to different operating companies under the division of mining rights lines, and the situation where multiple companies compete to develop the same gas reservoir will become more and more common. The development cost of large natural gas reservoirs is high and the risk is high. How to formulate scientific and reasonable development technology countermeasures for one's own side in the face of unfavorable competitive mining, improve the development benefits of one's own company and reduce development risks is a major issue in achieving efficient development of gas reservoirs in the current period of low oil prices.

[0003] At present, there are very few technologies that can be used for reference at home and abroad. The formulation of existing technical countermeasures for gas reservoir development mainly considers how to maximize the gas reservoir development effect under a single mining right. For example, patent CN115146889A discloses a gas reservoir development value assessment method, which first obtains gas reservoir data, including gas reservoir flavor, proved reserves of gas reservoirs, etc., and obtains the development value of each gas reservoir based on a pre-constructed gas reservoir development value assessment calculation formula. Then, based on the development value of each gas reservoir, the development value is ranked from large to small, and the ranking of the development value of each gas reservoir is used to guide the industrial development of the gas reservoir; for example, patent CN112081560B discloses a method for developing deep offshore high-temperature and overpressure gas reservoirs, which determines the effective development strategy and key parameter limits of the study block through in-depth research on the seepage mechanism and exhaustion law of the gas reservoir, the water breakthrough mechanism, and the changes in key reservoir parameters after water breakthrough, and based on the results of physical simulation experiments and mathematical model studies.

[0004] However, comparative analysis shows that these methods are not suitable for the formulation and optimization of development technology countermeasures for the same gas reservoir in the context of competitive exploitation by different operators. The following problems exist: (1) The development cost of large gas reservoirs is high and the risk is high. The efficient development of gas reservoirs cannot only consider the degree of recovery, but also needs to take into account the recovery rate and economic cost; (2) In the past, the rights and interests of gas reservoirs mostly belonged to the same operating unit. When the same gas reservoir faces competitive exploitation by different operators, especially in the unfavorable situation where the non-cooperative work area is developed earlier than the own work area, how to scientifically formulate the exploitation speed to reduce the development risk of the own work area and maximize the benefits, there is no experience to draw on. Summary of the invention

[0005] In order to solve the problem of gas reservoirs facing competitive exploitation by different operators, especially the unfavorable situation that the non-cooperative work area is developed earlier than the existing work area, the method of the present invention can scientifically formulate the exploitation speed, while taking into account the recovery rate and economic cost, to achieve maximum benefit.

[0006] In order to solve any of the above technical problems, the specific technical solutions of the embodiments of this specification are as follows:

[0007] In one aspect, the present invention provides a method for optimizing gas production rate in a competitive gas reservoir, the method comprising:

[0008] Obtain the remaining geological reserves of the gas reservoir before the first work area is put into production; the first work area is the existing work area;

[0009] Determine a first development index for a first work area based on the remaining geological reserves, and predict a second development index for a second work area; the second work area is a non-cooperative work area;

[0010] Establishing a gas reservoir numerical model to predict a first development result of the first work area at the end of a period when the first work area is developed at a first development index and the second work area is developed at a second development index simultaneously;

[0011] The initial gas production rate of the first work area is optimized based on the first development result, the first simulated gas production rate and the second simulated gas production rate.

[0012] Furthermore, the remaining geological reserves of the gas reservoir before the first work area is put into production include:

[0013] Obtaining geological parameters of the first work area; the geological parameters include: formation pressure before production, underground natural gas volume coefficient under formation pressure before production, gas-bearing area, effective reservoir thickness, effective porosity, and original gas saturation parameters;

[0014] The remaining geological reserves G of the gas reservoir before production in the first work area under the developed situation of the second work area are calculated based on the following formula:

[0015]

[0016] Among them, Ag is the gas-bearing area, h is the effective thickness of the reservoir, Φ is the effective porosity, Sg is the original gas saturation parameter, and Bg is the natural gas volume coefficient under the formation pressure before production.

[0017] Further, determining the first development index of the first work area based on the remaining geological reserves includes:

[0018] Based on the remaining geological reserves of the gas reservoir before the first work area is put into production, determine the maximum gas production scale and the initial gas production scale of the first work area;

[0019] Determine the number of first production wells that can be deployed in the first work area based on the reservoir distribution plane obtained by seismic prediction;

[0020] Based on the remaining geological reserves and gas reservoir characteristics of the gas reservoir before the first work area is put into production, determine the maximum gas production rate and the minimum gas production rate that can be achieved in the first work area;

[0021] Based on the maximum gas production rate and the minimum gas production rate, multiple first simulated gas production rates are obtained, and according to the first number of production wells, the single-well average production allocation corresponding to the multiple first production wells in the first work area at multiple different first simulated gas production rates is determined.

[0022] Furthermore, the second development indicators of the second work area are predicted to include:

[0023] Determine the current gas production rate of the second work area and evaluate the pre-gas production rate; wherein the current gas production rate of the second work area refers to the gas production rate of the second work area from the development of the second work area to the production of the first work area; the pre-gas production rate of the second work area refers to the gas production rate of the second work area under the situation of competitive exploitation after the production of the first work area;

[0024] Based on the current gas production speed and the pre-gas production speed, a plurality of second simulated gas production speeds are obtained, and different gas production scales corresponding to the second work area under the plurality of different second simulated gas production speeds are determined;

[0025] According to the number of second production wells that can be deployed in the second work area, the average production allocation of a single well at the current gas production rate and the average production allocation of a well at multiple different second simulated gas production rates are determined.

[0026] Furthermore, establishing a gas reservoir numerical model includes:

[0027] Establishing an original geological model of the gas reservoir and fitting the original geological reserves of the gas reservoir; the original geological model of the gas reservoir includes: a first work area model and a second work area model, and the original geological reserves of the gas reservoir are the sum of the original geological reserves of the first work area and the original geological reserves of the second work area;

[0028] The original geological model of the gas reservoir is converted into a gas reservoir numerical model, and the existing production data of the second work area is used to perform production history matching of existing gas wells.

[0029] Furthermore, the method further comprises:

[0030] The predicted simulation value is based on the gas reservoir numerical model; the predicted simulation value is a first development result of the first work area at the end of the period predicted based on the first development index of the first work area and the second development index of the second work area when the first work area and the second work area are developed simultaneously; the first development result is the cumulative gas production and stable production years of the first work area at the end of the prediction period.

[0031] Further, optimizing the initial gas production rate of the first work area based on the first development result, the first simulated gas production rate, and the second simulated gas production rate includes:

[0032] Establishing a relationship curve between the internal rate of return of the first work area and the first simulated gas production rate, and selecting a gas production rate range of the first work area based on the relationship curve;

[0033] calculating a development risk value of the first work area when the second work area is developed at a second simulated gas production rate;

[0034] The initial gas production rate of the first work area is optimized based on the gas production rate range and the development risk value.

[0035] In another aspect, the present invention provides a competitive gas reservoir production rate optimization device, the device comprising:

[0036] The first acquisition unit is used to acquire the remaining geological reserves of the gas reservoir before the first work area is put into production; the first work area is the existing work area;

[0037] A second acquisition unit is used to determine a first development index of a first work area based on the remaining geological reserves, and predict a second development index of a second work area; the second work area is a non-cooperative work area;

[0038] A model building unit, used to build a gas reservoir numerical model to predict a first development result of the first work area at the end of a period when the first work area is developed at a first development index and the second work area is developed at a second development index simultaneously;

[0039] An optimization unit is used to optimize the initial gas production rate of the first work area based on the first development result, the first simulated gas production rate and the second simulated gas production rate.

[0040] On the other hand, the present invention further provides a computer device, comprising a memory, a processor, and a computer program stored in the memory, wherein the processor implements the above method when executing the computer program.

[0041] On the other hand, the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and the computer program implements the above method when executed by a processor.

[0042] Finally, the present invention also provides a computer program product, which includes a computer program, and the computer program implements the above method when executed by a processor.

[0043] The competitive exploitation gas reservoir production speed optimization method and device of the present invention can solve the situation where the gas reservoir faces competitive exploitation by different operators, especially the unfavorable situation that the non-cooperative work area is developed earlier than the operator's work area, and the production speed can be scientifically customized while taking into account the recovery rate and economic cost to maximize the benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of this specification or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the embodiments of this specification. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 The figure shows a flow chart of a method for optimizing gas production rate of competitive gas reservoir production in an embodiment of this specification;

[0046] Figure 2 It is a schematic diagram of the structure of a gas production rate optimization device for competitive gas reservoir production in the embodiment of this specification;

[0047] Figure 3 The figure shows the relationship between the internal rate of return and the gas production rate of the working area in the embodiment of this specification;

[0048] Figure 4 The figure shows the expected profit and loss value and the expected regret value of the internal rate of return under different gas production rates in the own work area in the embodiment of this specification;

[0049] Figure 5 The figure shows the results of the quantitative analysis of the comprehensive internal rate of return and development risks in the embodiments of this specification;

[0050] Figure 6 The figure is a schematic diagram of the structure of a computer device in an embodiment of the present specification.

[0051]

Description of the accompanying drawings

[0052] 201. A first acquiring unit;

[0053] 202. A second acquisition unit;

[0054] 203. Model building unit;

[0055] 204. Optimization unit;

[0056] 602. Computer equipment;

[0057] 604, processor;

[0058] 606. Memory;

[0059] 608, driving mechanism;

[0060] 610, input / output module;

[0061] 612. Input devices;

[0062] 614. Output devices;

[0063] 616. Presentation equipment;

[0064] 618. Graphical user interface;

[0065] 620, network interface;

[0066] 622, communication link;

[0067] 624. Communication bus. DETAILED DESCRIPTION

[0068] The following will be combined with the drawings in the embodiments of this specification to clearly and completely describe the technical solutions in the embodiments of this specification. Obviously, the described embodiments are only part of the embodiments of this specification, not all of them. Based on the embodiments in the embodiments of this specification, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the embodiments of this specification.

[0069] It should be noted that the terms "first", "second", etc. in the description and claims of the embodiments of this specification and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the embodiments of this specification described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, device, product or equipment that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0070] It should be noted that the acquisition, storage, use, and processing of data in the technical solution of this application are in compliance with the relevant provisions of relevant laws and regulations. The order of steps listed in the embodiment is only one way of executing the steps among many steps, and does not represent the only execution order. When the actual system or device product is executed, it can be executed in the order or in parallel according to the method shown in the embodiment or the accompanying drawings.

[0071] The specific embodiment of the present invention discloses a method for optimizing the gas production rate of a competitive gas reservoir, such as Figure 1 As shown, the method includes:

[0072] Step 101, obtaining the remaining geological reserves of the gas reservoir before production in the first work area; the first work area is the existing work area. Before optimizing the gas production rate, it is necessary to evaluate the remaining geological reserves of the gas reservoir before production, and determine the subsequent development indicators and optimize the gas production rate based on the evaluation results.

[0073] Step 102, based on the remaining geological reserves, determine the first development index of the first work area, and predict the second development index of the second work area; the second work area is a non-cooperative work area. Specifically, the first development index may include: the maximum gas production scale and initial gas production scale of the first work area, the number of production wells that can be deployed in the first work area, the maximum gas production rate, the minimum gas production rate and the first simulated gas production rate that can be achieved in the first work area, and the single well average production of the first production well in the first work area under multiple different first simulated gas production rates. Among them, the first simulated gas production rate is determined based on the maximum gas production rate and the minimum gas production rate that can be achieved in the first work area, and the number of the first simulated gas production rates depends on the size of the model. The second development index may include: the current gas production rate and the pre-gas production rate of the second work area, the second simulated gas production rate, the single well average production of the second production well in the second work area under the current gas production rate, and the well average production under multiple different second simulated gas production rates. Among them, the second simulated gas production rate is obtained based on the current gas production rate and the pre-gas production rate, and its number is also related to the size of the model.

[0074] Step 103, establish a gas reservoir numerical model to predict the first development result of the first work area at the end of the period when the first work area is developed under a first development index and the second work area is developed under a second development index. Specifically, the first development result mainly includes the cumulative gas production and stable production years of the first work area at the end of the prediction period.

[0075] Step 104, based on the first development result, the first simulated gas production rate and the second simulated gas production rate, optimize the initial gas production rate of the first work area. Specifically, referring to the cumulative gas production and stable production years of the first work area at the end of the forecast period, and combining the first simulated gas production rate and the second simulated gas production rate, the numerical simulation is performed under the gas reservoir numerical model, and finally the most reasonable gas production rate is obtained based on the optimal development index as the optimized initial gas production rate of the first work area.

[0076] The method described in the embodiment of the present invention preferably optimizes the initial gas production rate of the own work area through the optimal development index of the first work area when the same gas reservoir faces a competitive development scenario, especially when the non-cooperative work area is developed earlier than the own work area. This can effectively reduce the development risk of the own work area and maximize the economic benefits of the own work area.

[0077] In one embodiment of the present specification, the volumetric method is used to calculate the remaining geological reserves of the first work area before production when the second work area has been developed. Specifically, obtaining the remaining geological reserves of the gas reservoir before production in the first work area includes:

[0078] Obtaining geological parameters of the first work area; the geological parameters include: formation pressure before production, underground natural gas volume coefficient of formation pressure before production, gas-bearing area, effective reservoir thickness, effective porosity, and original gas saturation parameters;

[0079] The remaining geological reserves before production of the first work area under the developed situation of the second work area are calculated based on the geological parameters. Specifically, the remaining geological reserves G of the gas reservoir before production of the first work area under the developed situation of the second work area are calculated based on the following formula:

[0080]

[0081] Among them, Ag is the gas-bearing area, h is the effective thickness of the reservoir, Φ is the effective porosity, Sg is the original gas saturation parameter, and Bg is the natural gas volume coefficient under the formation pressure before production.

[0082] In one embodiment of the present specification, determining the first development index of the first work area based on the remaining geological reserves includes:

[0083] Based on the remaining geological reserves of the gas reservoir before the first work area is put into production, determine the maximum gas production scale and the initial gas production scale of the first work area;

[0084] Determine the number of first production wells that can be deployed in the first work area based on the reservoir distribution plane obtained by seismic prediction;

[0085] Based on the remaining geological reserves and gas reservoir characteristics of the gas reservoir before the first work area is put into production, determine the maximum gas production rate and the minimum gas production rate that can be achieved in the first work area;

[0086] Based on the maximum gas production rate and the minimum gas production rate of the first work area, multiple first simulated gas production rates Vi are obtained, and the single-well average production corresponding to multiple first production wells in the first work area under multiple different first simulated gas production rates is determined according to the number of the first production wells. Specifically, the maximum gas production rate and the minimum gas production rate that can be achieved in the first work area are determined by analogy, and then multiple first simulated gas production rates Vi are obtained by the following formula:

[0087]

[0088] Among them, V i is the gas production speed, Vmax is the maximum gas production speed, Vmin is the minimum gas production speed, n is an integer, and the possible values ​​are 2, 3,…10.

[0089] In one embodiment of the present specification, predicting the second development index of the second work area includes:

[0090] Determine the current gas production rate of the second work area and evaluate the pre-gas production rate; the current gas production rate of the second work area refers to the gas production rate of the second work area after the development of the second work area and before the first work area is put into production; the pre-gas production rate of the second work area refers to the gas production rate of the second work area under the situation of competitive exploitation after the first work area is put into production. In this step, considering that the second work area may change its current gas production rate in the future, it is also necessary to evaluate the pre-gas production rate.

[0091] Based on the current gas production speed and the pre-gas production speed, a plurality of second simulated gas production speeds are obtained, and different gas production scales corresponding to the second work area under the plurality of different second simulated gas production speeds are determined;

[0092] According to the number of second production wells that can be deployed in the second work area, the average production allocation of a single well at the current gas production rate and the average production allocation of a well at multiple different second simulated gas production rates are determined. The number of second production wells includes the number of production wells currently in production and the number of production wells that may be newly deployed.

[0093] In one embodiment of the present specification, establishing a gas reservoir numerical model includes:

[0094] Establish an original geological model of the gas reservoir and fit the original geological reserves of the gas reservoir; the original geological model of the gas reservoir includes: a first work area model and a second work area model, and the original geological reserves of the gas reservoir are the sum of the original geological reserves of the first work area and the original geological reserves of the second work area. The first work area model and the second work area model are divided by the mining right line.

[0095] The original geological model of the gas reservoir is converted into a gas reservoir numerical model, and the existing production data of the second work area is used to perform history fitting on the gas reservoir numerical model with the existing gas well production data to ensure the reliability of the gas reservoir numerical model.

[0096] Specifically, the gas reservoir numerical model carries out multi-scenario numerical simulation and prediction. Since the development of the second work area will utilize the geological reserves of the first work area, the numerical simulation needs to consider the production of the second work area, design a combination plan and evaluate the development effect of the first work area.

[0097] In one embodiment of the present specification, reliability analysis and evaluation of the static geological data and dynamic production indicator data sources of the second work area and the first work area are carried out; the reliability analysis and evaluation mainly divides the accuracy of the data, wherein the data and information of the first work area are reliable data, and the data obtained in the second work area are modifiable data.

[0098] The existing production data of the second work area is used to perform historical matching of the existing gas well production data. According to the type and reliability of the existing production data of the second work area, the unreliable data and model parameters are corrected, and the remaining geological reserves of the gas reservoir before production in the first work area under the influence of the development of the second work area are matched to ensure the reliability of the model.

[0099] Specifically, the permeability field parameters of the gas reservoir are adjusted, the existing oil pressure data of the gas wells in the second work area are fitted, and the standard deviation of the absolute error E is determined according to the following formula: as Less than 1%;

[0100]

[0101] Among them, Cp is the fitted pressure value in the numerical model, rp is the pressure value of the actual gas well, cn is the fitted production of the gas well in the numerical model, rn is the production value of the actual gas well, and m and n are the number of fitting data points.

[0102] In one embodiment of the present specification, the method further includes:

[0103] The predicted simulation value is based on the gas reservoir numerical model; the predicted simulation value is a first development result of the first work area at the end of the period predicted based on the first development index of the first work area and the second development index of the second work area when the first work area and the second work area are developed simultaneously; the first development result is the cumulative gas production and stable production years of the first work area at the end of the prediction period.

[0104] Through a systematic analysis of the gas reservoir development potential of the second work area, the probability of the second work area adopting different second simulated gas production rates in the future is comprehensively evaluated. When there is no further production increase potential in the second work area, the maximum probability of maintaining the current gas production rate is 60%, and the probability of further increasing production and reducing the production rate is reduced. When there is further production increase potential in the second work area, the maximum probability of further increasing the production rate is 40%. As shown in Table 1.

[0105] Table 1 Probability classification of different second simulated gas production rates under different scenarios in the second work area

[0106]

[0107] In one embodiment of the present specification, optimizing the initial gas production rate of the first work area based on the first development result includes:

[0108] Establish a relationship curve between the internal rate of return of the first work area and the first simulated gas production speed, and screen the gas production speed range of the first work area based on the relationship curve. Among them, the expected value of the rate of return first increases and then decreases with the increase of gas production speed. Specifically, the gas production speed of the gas reservoir is not positively correlated with the internal rate of return, and presents an asymmetric parabolic relationship. As the gas production speed increases, the internal rate of return gradually increases. When the production speed increases to a certain extent, the internal rate of return begins to decline. The reason is that when the gas production speed is too high, the stable production time of the gas reservoir is shortened, the development investment increases, and the payback period increases, affecting the internal rate of return. Therefore, although facing multiple exploitation, the gas reservoir gas production speed is not the higher the better, but there is a relative benefit gas production speed range.

[0109] Calculate the development risk value of the first work area when the second work area is developed at the second simulated gas production rate. Specifically, the development risk value includes the maximum expected profit and loss value and the minimum regret value. Generally, the maximum expected profit and loss value or the minimum regret value is selected as the initial gas production rate of the first work area in the optimal solution. Among them,

[0110] The maximum expected profit and loss value is calculated using the following formula:

[0111] The minimum regret expected value is calculated using the following formula:

[0112] Where: E(x) represents the expected value of profit and loss of variable X, which is the first simulated gas production rate in the present invention; P j represents the probability value of the jth column (j=1, 2, ..., n); a ji Indicates A i The profit and loss value under the scenario j in the scheme. e(x) represents the expected value of the regret value of the variable X, which is the first simulated gas production rate in the present invention; W i Indicates A i The maximum value in the scheme. Among them, the expected value of regret first decreases and then increases, and the gas production rate range of the maximum expected value and the minimum regret value coincides.

[0113] The initial gas production rate of the first work area is optimized based on the gas production rate range and the development risk value. Specifically, a reasonable gas production rate that can simultaneously meet the higher internal benefit rate and lower development risk of the first work area is preferably used as the initial gas production rate.

[0114] Based on the same inventive concept, the embodiment of this specification also provides a competitive gas reservoir production rate optimization device, such as Figure 2 As shown, the device comprises:

[0115] The first acquisition unit 201 is used to acquire the remaining geological reserves of the gas reservoir before the first work area is put into production; the first work area is the existing work area;

[0116] A second acquisition unit 202 is used to determine a first development index of a first work area based on the remaining geological reserves, and predict a second development index of a second work area; the second work area is a non-cooperative work area;

[0117] The model building unit 203 is used to build a gas reservoir numerical model to predict a first development result of the first work area at the end of the period when the first work area is developed under a first development index and the second work area is developed under a second development index at the same time;

[0118] The optimization unit 204 is used to optimize the initial gas production rate of the first work area based on the first development result, the first simulated gas production rate and the second simulated gas production rate.

[0119] The present invention also includes a specific embodiment. High-sulfur gas reservoirs require large ground construction investment for development. In the face of competitive development scenarios, especially in the unfavorable situation where the non-cooperative work area is developed earlier than the own work area, it is of great significance to scientifically formulate the optimal development indicators of the own work area, effectively reduce development risks and maximize the economic benefits of the own side. This embodiment takes the high-sulfur gas reservoir in Block X as an example to provide a method for formulating optimal development technical countermeasures for competitive mining of high-sulfur gas reservoirs. The original temperature of the gas reservoir is 90°C, the original formation pressure is about 50MPa, the H2S content is 156g / m3, the effective porosity is 5.5%, and the connectivity is good. However, affected by the mining right line, the gas reservoir can be divided into the non-cooperative work area and the own work area on the plane. The non-cooperative work area has been developed and produced for nearly 10 years, and part of the geological reserves of the own work area have been used, resulting in a continuous decrease in the formation pressure of the own work area, while the own work area has not yet been put into production and is planned to be put into development. The optimal development indicators need to be formulated through the following steps, including the following steps:

[0120] Step 1: Conduct an assessment of the remaining geological reserves before the work area is put into production, including:

[0121] S1. Through the measured downhole pressure data of multiple exploration wells in our own work area, we can obtain the formation pressure of 28.8MPa before our own work area is put into production;

[0122] S2. Use the high-sulfur gas sample at the wellhead to carry out indoor high-temperature and high-pressure PVT testing to obtain the natural gas volume coefficient at the corresponding formation pressure in the own work area;

[0123] S2. Through the inversion of seismic data and combined with indoor experimental tests, the gas-bearing area, effective reservoir thickness, effective porosity, and original gas saturation parameters in the work area are obtained;

[0124] S3. Use the volumetric method to calculate the current remaining geological reserves of 25.066 billion cubic meters in our own work area under the development of the non-cooperative work area.

[0125] Step 2: Determine the development indicators for the non-cooperative work area and the own work area, including:

[0126] S1. By analogy, the upper limit of the gas production rate in our work area is determined to be 8.5%. Combined with the production needs of our company, the initial recommended gas production rate range is between 4.5% and 8.5%;

[0127] S2. Determine the maximum gas production scale and initial gas production scale of the own work area based on the remaining geological reserves of 25.066 billion cubic meters before the production of the own work area and the initially recommended gas production rate range;

[0128] S3. Combined with the high-quality reservoir distribution plane obtained from seismic prediction, it is determined that the number of production wells that can be deployed in the own work area is 10;

[0129] S4. Determine the corresponding single well production allocation at different gas production rates in the own work area. The average single well production allocation in the own work area is 800,000 cubic meters per day;

[0130] S5. Determine the current gas production rate of the non-cooperative work area as 6.5%, and evaluate the possible future gas production rate of the non-cooperative work area to be between 5.5% and 8.5%, wherein the probability of the non-cooperative work area maintaining the current gas production rate of 6.5% is 60%, the probability of increasing the gas production rate to 7.5% is 20%, the probability of increasing the gas production rate to 8.5% is 10%, and the probability of reducing the gas production rate to 5.5% is 10%;

[0131] S6. Determine the corresponding gas production scale under different gas production speeds in the non-cooperative work area;

[0132] S7. Determine the average production allocation of a single well at the current gas production rate and the average production allocation of wells at different production rates based on the number of wells in production in the non-cooperative work area and the number of wells that can be newly deployed;

[0133] Step 3: Establish a gas reservoir numerical model to predict the development effects of the non-cooperative work area and the own work area under different development indicators:

[0134] S1. Establish an original geological model of the gas reservoir, and the original geological reserves in the geological simulation are 133.8 billion cubic meters; the original geological model of the gas reservoir includes the original geological reserves of the own work area and the non-cooperative work area, and the original geological reserves include the original geological reserves of 41 billion cubic meters in the own work area and the original geological reserves of 92.8 billion cubic meters in the non-cooperative work area.

[0135] S2. Convert the geological model into a gas reservoir numerical model, and set up zones based on the mineral rights line. The working area is set as Zone A, and the non-working area is set as Zone B;

[0136] S3. Conduct reliability analysis and evaluation of static geological data and dynamic production index data sources in non-cooperative work areas and own work areas;

[0137] The reliability analysis and evaluation mentioned above mainly divides the accuracy of data, among which the data and data of the party's work area are reliable data, such as pressure, reserves, number of wells, well location coordinates and other parameters. Since it is difficult to accurately obtain the static and production dynamic parameters of the non-cooperative work area, the data of the non-cooperative work area obtained are modifiable data, such as pressure, reserves, number of wells, well location coordinates, cumulative gas production, single well production dynamic data, etc. of the non-cooperative work area;

[0138] S4. Carry out historical fitting of the gas reservoir numerical model, grade the use of data according to the type and reliability of the data, correct unreliable data and model parameters, and fit the numerical model to find that the remaining geological reserves of Area A of our own work area before production is affected by the development of Area B of the non-cooperative work area are 24.56 billion cubic meters, which is basically consistent with the remaining geological reserves of our own work area before production calculated by the volumetric method under the situation that the non-cooperative work area has been developed, thus ensuring the reliability of the gas reservoir numerical model.

[0139] S5. Use the revised numerical model to carry out multi-scenario numerical simulation and prediction. Since the development of the non-cooperative work area will mobilize the geological reserves of our own work area, the numerical simulation needs to take the production of neighboring areas into consideration. A total of 20 simulation schemes are designed to carry out multi-scenario numerical simulations of our own work area with gas production rates of 4.5%, 5.5%, 6.5%, 7.5% and 8.5%, and the corresponding production scale and single well allocation, and the non-cooperative work area with gas production rates of 5.5%, 6.5%, 7.5%, 8.5%, and the corresponding production scale and single well allocation, to obtain the stable production years and cumulative gas production of our own work area at the end of the 20-year forecast period.

[0140] Step 4: Conduct benefit-oriented quantitative analysis to determine the optimal development indicators

[0141] S1. Establish a curve chart showing the relationship between the internal rate of return and gas production rate in the work area, such as Figure 3 shown.

[0142] S2. Analysis found that the gas production rate of gas reservoirs is not positively correlated with the internal rate of return, but presents an asymmetric parabolic relationship. With the increase of production rate, the internal rate of return gradually increases. When the production rate increases to a certain extent, the internal rate of return begins to decline. The reason is that when the gas production rate is too high, the stable production time of the gas reservoir is shortened, the development investment increases, and the payback period increases, which affects the internal rate of return. Therefore, although facing multiple exploitation, the gas production rate of the gas reservoir is not the higher the better, but there is a relatively optimal gas production rate. Figure 3 , select the gas production rate range of 5% to 7% in the existing work area that can obtain a higher internal rate of return;

[0143] S3. Calculate the expected profit and loss and expected regret value of the internal rate of return of the own work area under different scenarios with different mining speeds, such as Figure 4The results show that the expected value of the internal rate of return in the study area increases first and then decreases with the increase of gas production rate, while the expected value of regret decreases first and then increases. The production rate intervals of the maximum expected value and the minimum regret value coincide with each other. The gas production rate interval with the minimum regret value / expected value is 5.5% to 6.5%, and the development risk is the lowest.

[0144] S4. Comprehensive internal rate of return and development risk quantitative analysis results, such as Figure 5 As shown, the gas production rate in the study area should be between 5.5% and 6.5%, the internal rate of return index is better, and the development risk is relatively small.

[0145] like Figure 6 As shown, a computer device provided in an embodiment of the present invention, the apparatus in this specification may be a computer device in this embodiment, and the method of the above-mentioned specification is executed. The computer device 602 may include one or more processors 604, such as one or more central processing units (CPUs), and each processing unit may implement one or more hardware threads. The computer device 602 may also include any memory 606, which is used to store any kind of information such as code, settings, data, etc. Non-limiting, for example, the memory 606 may include any one or more combinations of the following: any type of RAM, any type of ROM, flash memory device, hard disk, optical disk, etc. More generally, any memory may use any technology to store information. Further, any memory may provide volatile or non-volatile retention of information. Further, any memory may represent a fixed or removable component of the computer device 602. In one case, when the processor 604 executes an associated instruction stored in any memory or a combination of memories, the computer device 602 may perform any operation of the associated instruction. The computer device 602 also includes one or more drive mechanisms 608 for interacting with any memory, such as a hard disk drive mechanism, an optical disk drive mechanism, etc.

[0146] The computer device 602 may also include an input / output module 610 (I / O) for receiving various inputs (via input devices 612) and for providing various outputs (via output devices 614). A specific output mechanism may include a presentation device 616 and an associated graphical user interface (GUI) 618. In other embodiments, the input / output module 610 (I / O), the input device 612, and the output device 614 may not be included, and the computer device 602 may be used as a computer device in a network. The computer device 602 may also include one or more network interfaces 620 for exchanging data with other devices via one or more communication links 622. One or more communication buses 624 couple the components described above together.

[0147] The communication link 622 may be implemented in any manner, for example, through a local area network, a wide area network (e.g., the Internet), a point-to-point connection, etc., or any combination thereof. The communication link 622 may include any combination of hardwired links, wireless links, routers, gateway functions, name servers, etc. governed by any protocol or combination of protocols.

[0148] The embodiments of the present specification also provide a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and the computer program implements the above method when executed by a processor.

[0149] The embodiments of the present specification also provide a computer-readable instruction, wherein when a processor executes the instruction, the program therein causes the processor to execute the above method.

[0150] It should be understood that in the various embodiments of the present specification, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present specification.

[0151] It should also be understood that in the embodiments of this specification, the term "and / or" is only a description of the association relationship of the associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in the embodiments of this specification generally indicates that the associated objects before and after are in an "or" relationship.

[0152] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed in the embodiments of this specification can be implemented with electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the embodiments of this specification.

[0153] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0154] In the several embodiments provided in the embodiments of this specification, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, or it can be an electrical, mechanical or other form of connection.

[0155] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the embodiments of this specification.

[0156] In addition, each functional unit in each embodiment of the present specification can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The above integrated unit can be implemented in the form of hardware or in the form of software functional units.

[0157] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of this specification is essentially or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the embodiment of this specification. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program code.

[0158] The embodiments of this specification use specific embodiments to illustrate the principles and implementation methods of the embodiments of this specification. The description of the above embodiments is only used to help understand the methods and core ideas of the embodiments of this specification. At the same time, for those skilled in the art, according to the ideas of the embodiments of this specification, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as a limitation on the embodiments of this specification.

Claims

1. A method for optimizing gas production rate in competitive gas reservoir development, characterized in that: The method comprises: Obtain the remaining geological reserves of the gas reservoir before the first work area is put into production; the first work area is the existing work area; Determine a first development index for a first work area based on the remaining geological reserves, and predict a second development index for a second work area; the second work area is a non-cooperative work area; Establishing a gas reservoir numerical model to predict a first development result of the first work area at the end of a period when the first work area is developed at a first development index and the second work area is developed at a second development index simultaneously; The initial gas production rate of the first work area is optimized based on the first development result, the first simulated gas production rate and the second simulated gas production rate.

2. The method for optimizing gas production rate in competitive gas reservoir development according to claim 1, characterized in that: The remaining geological reserves of the gas reservoir before the first work area is put into production include: Obtaining geological parameters of the first work area; the geological parameters include: formation pressure before production, underground natural gas volume coefficient under formation pressure before production, gas-bearing area, effective reservoir thickness, effective porosity, and original gas saturation parameters; The remaining geological reserves G of the gas reservoir before production in the first work area under the developed situation of the second work area are calculated based on the following formula: Among them, Ag is the gas-bearing area, h is the effective thickness of the reservoir, Φ is the effective porosity, Sg is the original gas saturation parameter, and Bg is the natural gas volume coefficient under the formation pressure before production.

3. The method for optimizing gas production rate in competitive gas reservoir development according to claim 1, characterized in that: Determining the first development index of the first work area based on the remaining geological reserves includes: Based on the remaining geological reserves of the gas reservoir before the first work area is put into production, determine the maximum gas production scale and the initial gas production scale of the first work area; Determine the number of first production wells that can be deployed in the first work area based on the reservoir distribution plane obtained by seismic prediction; Based on the remaining geological reserves and gas reservoir characteristics of the gas reservoir before the first work area is put into production, determine the maximum gas production rate and the minimum gas production rate that can be achieved in the first work area; Based on the maximum gas production rate and the minimum gas production rate, multiple first simulated gas production rates are obtained, and according to the first number of production wells, the single-well average production allocation corresponding to the multiple first production wells in the first work area at multiple different first simulated gas production rates is determined.

4. The method for optimizing gas production rate in competitive gas reservoir development according to claim 1, characterized in that: The second development indicators for the second work area are predicted to include: Determine the current gas production rate of the second work area and evaluate the pre-gas production rate; wherein the current gas production rate of the second work area refers to the gas production rate of the second work area from the development of the second work area to the production of the first work area; the pre-gas production rate of the second work area refers to the gas production rate of the second work area under the situation of competitive exploitation after the production of the first work area; Based on the current gas production speed and the pre-gas production speed, a plurality of second simulated gas production speeds are obtained, and different gas production scales corresponding to the second work area under the plurality of different second simulated gas production speeds are determined; According to the number of second production wells that can be deployed in the second work area, the average production allocation of a single well at the current gas production rate and the average production allocation of a well at multiple different second simulated gas production rates are determined.

5. The method for optimizing gas production rate in competitive gas reservoir development according to claim 1, characterized in that: The establishment of a gas reservoir numerical model includes: Establishing an original geological model of the gas reservoir and fitting the original geological reserves of the gas reservoir; the original geological model of the gas reservoir includes: a first work area model and a second work area model, and the original geological reserves of the gas reservoir are the sum of the original geological reserves of the first work area and the original geological reserves of the second work area; The original geological model of the gas reservoir is converted into a gas reservoir numerical model, and the existing production data of the second work area is used to perform production history matching of existing gas wells.

6. The method for optimizing gas production rate in competitive gas reservoir development according to claim 5, characterized in that: The method further comprises: The predicted simulation value is based on the gas reservoir numerical model; the predicted simulation value is a first development result of the first work area at the end of the period predicted based on the first development index of the first work area and the second development index of the second work area when the first work area and the second work area are developed simultaneously; the first development result is the cumulative gas production and stable production years of the first work area at the end of the prediction period.

7. The method for optimizing gas production rate in competitive gas reservoir development according to claim 1, characterized in that: Optimizing the initial gas production rate of the first work area based on the first development result, the first simulated gas production rate, and the second simulated gas production rate includes: Establishing a relationship curve between the internal rate of return of the first work area and the first simulated gas production rate, and selecting a gas production rate range of the first work area based on the relationship curve; calculating a development risk value of the first work area when the second work area is developed at a second simulated gas production rate; The initial gas production rate of the first work area is optimized based on the gas production rate range and the development risk value.

8. A device for optimizing gas production rate in competitive gas reservoir production, characterized in that: The device comprises: The first acquisition unit is used to acquire the remaining geological reserves of the gas reservoir before the first work area is put into production; the first work area is the existing work area; A second acquisition unit is used to determine a first development index of a first work area based on the remaining geological reserves, and predict a second development index of a second work area; the second work area is a non-cooperative work area; A model building unit, used to build a gas reservoir numerical model to predict a first development result of the first work area at the end of a period when the first work area is developed at a first development index and the second work area is developed at a second development index simultaneously; An optimization unit is used to optimize the initial gas production rate of the first work area based on the first development result, the first simulated gas production rate and the second simulated gas production rate.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory, characterized in that: When the processor executes the computer program, the method according to any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

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