A competitive exploitation gas reservoir gas production rate optimization method and device

Abstract

The present application relates to the technical field of oil and gas exploration and development, and particularly relates to a competitive gas reservoir exploitation gas production rate optimization method and device. The method comprises: obtaining the remaining geological reserves of a gas reservoir before the first work area is put into production; the first work area is a party work area; determining a first development index of the first work area based on the remaining geological reserves, and predicting a second development index of a second work area; the second work area is a non-cooperative party work area; a gas reservoir numerical model is established 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 development index and the second work area is developed under a second development index; and the initial gas production rate of the first work area is optimized based on the first development result. The method of the present application can scientifically determine the exploitation rate to reduce the development risk of the first work area and maximize the benefit.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil and gas exploration and development, and particularly relates to a method and device for optimizing gas production rate in competitive gas reservoir development. BACKGROUND

[0002] With the increasing frequency of mining right transfer, the same gas reservoir underground may be divided into different blocks by the mining right line, and the situation of multiple companies competing to develop the same gas reservoir will become more and more common. The development of large-scale gas reservoirs is high in cost and high in risk. How to develop scientific and reasonable development strategies in the face of competitive exploitation, improve the development efficiency of the company and reduce the development risk is a major issue for the benefit development of gas reservoirs in the current low oil price period.

[0003] At present, there are few technologies that can be used for reference at home and abroad. The existing gas reservoir development strategy is mainly to consider how to maximize the development effect of gas reservoirs under a single mining right. For example, patent CN115146889A discloses a gas reservoir development value evaluation method. First, the gas reservoir data is obtained, including gas reservoir taste, gas reservoir proven reserves, etc. The development value of each gas reservoir is obtained based on the pre-constructed gas reservoir development value evaluation formula. Then, based on the development value of each gas reservoir, the development value is sorted from large to small. The sorting 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 high-temperature and superpressure gas reservoirs on the sea. Through in-depth study of the percolation mechanism and depletion law of gas reservoirs, water breakthrough mechanism, and changes in key parameters of the reservoir after water breakthrough, and based on the results of physical simulation experiments and mathematical modeling, the effective development strategy and key parameter limits of the study block are determined.

[0004] However, comparative analysis shows that these methods are not suitable for developing technical strategies and optimization under the situation of competitive exploitation of the same gas reservoir by different operators. The following problems exist: (1) The development of large-scale gas reservoirs is high in cost and high in risk. Efficient development of gas reservoirs cannot only consider the recovery degree, but also needs to consider the recovery rate and economic cost; (2) The gas reservoir rights in the past belong to the same operating unit. Under the situation of competitive exploitation of the same gas reservoir by different operators, especially under the disadvantageous situation that the non-cooperative operator area is developed earlier than the operator area, how to scientifically determine the exploitation rate to reduce the development risk of the operator area and maximize the benefit is still a problem without reference experience. SUMMARY

[0005] To solve the problems caused by the situation of competitive exploitation of the same gas reservoir by different operators, especially under the disadvantageous situation that the non-cooperative operator area is developed earlier than the operator area, the method of the present application can scientifically determine the exploitation rate, taking into account the recovery rate and economic cost, and maximizing the benefit.

[0006] To solve any of the above technical problems, the specific technical solutions of the embodiments of the present specification are as follows:

[0007] In one aspect, the present application provides a competitive exploitation of gas reservoir gas production rate optimization method, the method comprises:

[0008] Obtaining the remaining geological reserves of the gas reservoir before the first work area is put into production; the first work area is a party work area;

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

[0010] Establish a gas reservoir numerical model to predict the first development result of the first work area at the end of the development under the first development index and the second development index under the second development index when the first work area and the second work area are developed at the same time;

[0011] 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.

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

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

[0014] Calculate the remaining geological reserves G of the gas reservoir before the first work area is put into production under the second work area development situation based on the following formula:

[0015]

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

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

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

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

[0020] determining a maximum gas production rate and a minimum gas production rate of the first work area based on the remaining geological reserves of the gas reservoir before the first work area is put into production and characteristics of the gas reservoir;

[0021] obtaining a plurality of first simulated gas production rates based on the maximum gas production rate and the minimum gas production rate, and determining well average production of a plurality of first production wells in the first work area under a plurality of different first simulated gas production rates according to the number of the first production wells.

[0022] Further, the second development index of the second work area includes:

[0023] determining a current gas production rate of the second work area and a predicted gas production rate, wherein the current gas production rate of the second work area is a gas production rate of the second work area after development of the second work area and before the first work area is put into production, and the predicted gas production rate of the second work area is a gas production rate of the second work area under a competitive exploitation situation after the first work area is put into production;

[0024] obtaining a plurality of second simulated gas production rates based on the current gas production rate and the predicted gas production rate, and determining different gas production scales of the second work area under a plurality of different second simulated gas production rates;

[0025] determining well average production under the current gas production rate and well average production under a plurality of different second simulated gas production rates according to the number of second production wells that can be deployed in the second work area.

[0026] Further, the gas reservoir numerical model includes:

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

[0028] converting the gas reservoir original geological model into a gas reservoir numerical model, and using existing production data of the second work area to perform existing gas well production history fitting.

[0029] Further, the method further includes:

[0030] predicting a simulation numerical value based on the gas reservoir numerical model; the prediction simulation numerical value is a first development result of the first work area at the end of the period 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 at the same time; the first development result is a cumulative gas production of the first work area at the end of the period and a stable production 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 screening a gas production rate interval 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 the second simulated gas production rate;

[0034] optimizing an initial gas production rate of the first work area based on the gas production rate interval and the development risk value.

[0035] In another aspect, the present application provides a device for optimizing gas production rate in competitive gas reservoir development, which comprises:

[0036] a first obtaining unit configured to obtain remaining geological reserves of a gas reservoir before production of a first work area; the first work area is a work area of a party;

[0037] a second obtaining unit configured to determine a first development index of the 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 work area of a non-party;

[0038] a model establishing unit configured to establish a numerical model of the gas reservoir to predict a first development result of the first work area at the end of the development when the first work area and the second work area are developed at the first development index and the second development index respectively;

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

[0040] In another aspect, the present application further provides a computer device comprising a memory, a processor and a computer program stored in the memory, and the processor executes the computer program to implement the above method.

[0041] In another aspect, the present application provides a computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement the above method.

[0042] Finally, the present application further provides a computer program product, which comprises a computer program, and the computer program is executed by a processor to implement the above method.

[0043] Through the method and device for optimizing gas production rate in competitive gas reservoir development, the gas production rate can be scientifically determined under the condition that the gas reservoir is developed by different operators, especially when the non-party work area is developed earlier than the party work area, and the recovery rate and economic cost are taken into account to maximize the benefit. BRIEF DESCRIPTION OF DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present specification or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present specification, and other drawings can be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0045] Figure 1 A competitive gas reservoir production rate optimization method flowchart in the embodiments of the present specification is shown.

[0046] Figure 2 A competitive gas reservoir production rate optimization device structure diagram in the embodiments of the present specification is shown.

[0047] Figure 3 A relationship curve between the internal rate of return of the own work area and the gas production rate in the embodiments of the present specification is shown.

[0048] Figure 4 A profit and loss expectation value and regret expectation value diagram of the internal rate of return of the own work area under different gas production rates in the embodiments of the present specification is shown.

[0049] Figure 5 A comprehensive internal rate of return and development risk quantitative analysis result diagram in the embodiments of the present specification is shown.

[0050] Figure 6 A computer device structure diagram in the embodiments of the present specification is shown.

[0051]

Explanation of reference numerals

[0052] 201, a first acquisition unit;

[0053] 202, a second acquisition unit;

[0054] 203, a model establishing unit;

[0055] 204, an optimization unit;

[0056] 602, a computer device;

[0057] 604, a processor;

[0058] 606, a memory;

[0059] 608, a driving mechanism;

[0060] 610, an input / output module;

[0061] 612, an input device;

[0062] 614, output device;

[0063] 616, presentation device;

[0064] 618, graphical user interface;

[0065] 620, network interface;

[0066] 622, communication link;

[0067] 624, communication bus. DETAILED DESCRIPTION

[0068] The technical solutions in the embodiments of the present specification will be described clearly and completely below in combination with the drawings in the embodiments of the present specification. Obviously, the described embodiments are only part of the embodiments of the present specification, rather than all the embodiments. Based on the embodiments in the embodiments of the present specification, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the embodiments of the present specification.

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

[0070] It should be noted that the acquisition, storage, use, processing, etc. of data in the technical solutions of the present application comply with the relevant provisions of relevant laws and regulations. The order of steps listed in the embodiments is only one of the many execution orders, and does not represent the only execution order. When the system or device product is executed in practice, it can be executed in sequence or in parallel according to the method shown in the embodiments or the drawings.

[0071] The embodiments of the present application disclose a competitive exploitation of gas reservoir gas production rate optimization method, as shown in Figure 1 The method comprises the following steps:

[0072] Step 101, obtaining the remaining geological reserves of a gas reservoir before production of a first work area; the first work area is a work area of a party. Before the optimization of the gas production rate, the remaining geological reserves of the gas reservoir before production need to be evaluated, and based on the evaluation results, subsequent development indexes are determined and the gas production rate is optimized.

[0073] Step 102, determining a first development index of the first work area based on the remaining geological reserves, and predicting a second development index of a second work area; the second work area is a work area of a non-partner party. Specifically, the first development index can include: a maximum gas production scale and an initial gas production scale of the first work area, a number of production wells that can be deployed in the first work area, a maximum gas production rate, a minimum gas production rate and a first simulated gas production rate that can be reached in the first work area, and a single well average production of a first production well in the first work area corresponding to a plurality of different first simulated gas production rates. The first simulated gas production rate is determined according to the maximum gas production rate and the minimum gas production rate that can be reached in the first work area, and the number of first simulated gas production rates is determined according to the size of the model. The second development index can include: a current gas production rate and a predicted gas production rate of the second work area, a second simulated gas production rate, a single well average production of a second production well in the second work area at the current gas production rate, and a well average production at a plurality of different second simulated gas production rates. The second simulated gas production rate is obtained based on the current gas production rate and the predicted gas production rate, and the number of second simulated gas production rates is also related to the size of the model.

[0074] Step 103, establishing 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 and the second work area are developed under the first development index and the second development index. Specifically, the first development result is mainly the cumulative gas production and the stable production period of the first work area at the end of the prediction period.

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

[0076] The method of the embodiment of the application can effectively reduce the development risk of the first work area and maximize the economic benefit of the first work area by optimizing the initial gas production rate of the first work area based on the optimal development index of the first work area, especially in the unfavorable situation that the non-partner party work area develops earlier than the party work area in the face of competitive development of the same gas reservoir.

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

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

[0079] calculating the remaining geological reserves of the first work area under the condition that the second work area has been developed based on the geological parameters. Specifically, the remaining geological reserves G of the gas reservoir of the first work area before production under the condition that the second work area has been developed is calculated based on the following formula:

[0080]

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

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

[0083] determining the maximum gas production scale and the initial gas production scale of the first work area based on the remaining geological reserves of the gas reservoir of the first work area before production;

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

[0085] determining the maximum gas production rate and the minimum gas production rate that can be reached in the first work area based on the remaining geological reserves of the gas reservoir of the first work area before production and the gas reservoir characteristics;

[0086] obtaining a plurality of first simulated gas production rates Vi based on the maximum gas production rate and the minimum gas production rate of the first work area, and determining the corresponding single-well average allocation of a plurality of first production wells in the first work area under a plurality of different first simulated gas production rates based on the number of first production wells. Specifically, the maximum gas production rate and the minimum gas production rate that can be reached in the first work area are determined by analogy, and a plurality of first simulated gas production rates Vi are obtained by the following formula:

[0087]

[0088] wherein V i is the gas production rate, Vmax is the maximum gas production rate, Vmin is the minimum gas production rate, and n is an integer, which can be 2, 3,..., 10.

[0089] In one embodiment of the present specification, the second development index of the second work area is predicted, comprising:

[0090] The current gas production rate of the second work area is determined, and the pre-gas production rate is evaluated; wherein the current gas production rate of the second work area is the gas production rate of the second work area after development 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, the pre-gas production rate also needs to be evaluated.

[0091] Based on the current gas production rate and the pre-gas production rate, a plurality of second simulated gas production rates are obtained, and different gas production scales of the second work area under a plurality of different second simulated gas production rates are determined.

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

[0093] In one embodiment of the present specification, the gas reservoir numerical model is established, comprising:

[0094] The original geological model of the gas reservoir is established, and the original geological reserves of the gas reservoir are fitted; 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. Wherein, the first work area model and the second work area model are divided by the division limit of 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 are 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 prediction. Since the development of the second work area will deplete the geological reserves of the first work area, the production of the second work area needs to be considered in the numerical simulation, and a combination scheme is designed and the development effect of the first work area is evaluated.

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

[0098] The existing production data of the second work area is used to perform history matching on the existing production data of the gas well. According to the type and reliability level of the existing production data of the second work area, unreliable data and model parameters are corrected, the remaining geological reserves of the gas reservoir before production of the first work area affected by the development of the second work area are fitted, and the reliability of the model is ensured.

[0099] Specifically, the gas reservoir permeability field parameter is adjusted, the existing gas well pressure data of the second work area is fitted, and the standard deviation E of the absolute error is confirmed according to the following formula as less than 1%;

[0100]

[0101] wherein Cp is the fitted pressure value in the numerical model, rp is the pressure value of the actual gas well, cn is the gas well fitting production 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 an embodiment of the present specification, the method further comprises:

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

[0104] By systematically analyzing the development potential of the second work area gas reservoir, the probability of using different second simulation gas production rates in the future is comprehensively evaluated. When there is no further production potential in the second work area, the probability of maintaining the current gas production rate is the largest, which is 60%, and the probability of further production and reducing the production rate decreases. When there is further production potential in the second work area, the probability of further increasing the production rate is the largest, which is 40%. As shown in Table 1.

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

[0106]

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

[0108] A relationship curve between the internal rate of return of the first work area and the first simulated gas production rate is established, and a gas production rate interval of the first work area is screened based on the relationship curve. The expected value of the rate of return increases and then decreases with the increase of the gas production rate. Specifically, the gas production rate of the gas reservoir is not positively correlated with the internal rate of return, and the relationship is an asymmetric parabolic relationship. With the increase of the gas production rate, the internal rate of return gradually increases, and when the gas production rate increases to a certain degree, the internal rate of return begins to decrease. 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 is increased, and the recovery period is increased, which affects the internal rate of return. Therefore, although facing multiple exploitations, the gas production rate of the gas reservoir is not the higher the better, but there is a relatively beneficial gas production rate interval.

[0109] A development risk value of the first work area when the second work area is developed at the second simulated gas production rate is calculated. Specifically, the development risk value includes a maximum profit and loss expectation value and a minimum regret value. Generally, the maximum profit and loss expectation value or the minimum regret value is selected as the initial gas production rate of the first work area in the optimal scheme. Wherein,

[0110] The maximum profit and loss expectation value adopts the following formula:

[0111] The minimum regret value expectation value adopts the following formula:

[0112] In the formula, E(x) represents a profit and loss expectation value of a variable X, which is the first simulated gas production rate in the application; P j represents a probability value of the jth column that may occur (j = 1, 2,..., n); a ji represents A i The profit and loss value of the jth scheme. e(x) represents a regret value expectation value of a variable X, which is the first simulated gas production rate in the application; W i represents A i The maximum value in the scheme. Wherein, the regret value expectation value first decreases and then increases, and the gas production rate interval of the maximum expectation 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 interval and the development risk value. Specifically, a reasonable gas production rate that can simultaneously satisfy a higher internal benefit rate of the first work area and a lower development risk is preferred as the initial gas production rate.

[0114] Based on the same inventive concept, the embodiments of the present application also provide a competitive exploitation gas reservoir gas production rate optimization device, as shown in Figure 2 The device comprises:

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

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

[0117] The model establishing unit 203 is configured to establish a gas reservoir numerical model to predict a first development result of the first work area at the end of development when the first work area and the second work area are developed simultaneously under the first development index and the second development index.

[0118] The optimization unit 204 is configured to optimize an 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 application also includes a specific embodiment. High-sulfur gas reservoirs have a large investment in development ground construction. In the face of competitive development scenarios, especially in the unfavorable situation that non-cooperative work areas are developed earlier than cooperative work areas, scientifically formulating the optimal development index of the cooperative work area can effectively reduce the development risk and maximize the economic benefit of the cooperative work area. This embodiment takes a high-sulfur gas reservoir in X block as an example to provide a method for formulating an optimal development technical countermeasure for competitive exploitation of high-sulfur gas reservoirs. The original temperature of the gas reservoir is 90℃, the original formation pressure is about 50MPa, the H2S content is 156g / m3, the effective porosity is 5.5%, the connectivity is good, but the gas reservoir can be divided into non-cooperative work areas and cooperative work areas on the plane due to the influence of the mining right line. The non-cooperative work area has been developed for nearly 10 years, and part of the geological reserves of the cooperative work area has been used, resulting in a continuous decrease in the formation pressure of the cooperative work area. The cooperative work area has not yet been put into production and is planned to be developed. The optimal development index needs to be formulated through the following steps, including the following steps:

[0120] Step one: carry out the remaining geological reserves evaluation of the cooperative work area before production, specifically including:

[0121] S1, obtain the formation pressure of the cooperative work area before production through the downhole pressure measured data of multiple exploration wells of the cooperative work area, which is 28.8MPa;

[0122] S2, carry out indoor high-temperature and high-pressure PVT test by using wellhead high-sulfur gas samples to obtain the gas volume factor under the corresponding formation pressure in the cooperative work area;

[0123] S2, obtain the gas-bearing area, reservoir effective thickness, effective porosity and original gas saturation parameters in the cooperative work area through inversion of seismic data and indoor experimental test;

[0124] S3, calculate the current remaining geological reserves of the cooperative work area under the developed situation of the non-cooperative work area by using the volumetric method, which is 250.66 billion cubic meters.

[0125] Step two: determine the development index of non-cooperative work area and the development index of the other party, including:

[0126] S1, determine the upper limit of the gas production rate of the self work area by analogy method as 8.5%, and preliminarily recommend the gas production rate interval between 4.5% and 8.5% in combination with the production demand of the self company;

[0127] S2, determine the maximum gas production scale and the initial gas production scale of the self work area in combination with the remaining geological reserves 25.066 billion cubic meters before the production of the self work area and the preliminarily recommended gas production rate interval;

[0128] S3, determine the number of deployable production wells in the self work area in combination with the distribution plane of the high-quality reservoir predicted by the earthquake, which is 10;

[0129] S4, determine the single well production allocation of the self work area under different gas production rates, and the single well production allocation of the self 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 pre-gas production rate of the non-cooperative work area between 5.5% and 8.5%, wherein the probability of maintaining the current gas production rate of 6.5% of the non-cooperative work area 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 gas production scale of the non-cooperative work area under different gas production rates;

[0132] S7, determine the single well average production allocation under the current gas production rate and the well average production allocation under different gas production rates according to the number of production wells and the number of deployable well sites in the non-cooperative work area;

[0133] Step three: establish a gas reservoir numerical model to predict the development effect of the non-cooperative work area and the self work area under different development indexes:

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

[0135] S2, convert the geological model into a gas reservoir numerical model, and set the boundary with the mining right line, set the self work area as area A and the non-self work area as area B;

[0136] S3, analyze and evaluate the reliability of the static geological data and dynamic production index data sources of the non-cooperative work area and the self work area;

[0137] The reliability analysis and evaluation is mainly to divide the accuracy of data, wherein the data of the party's work area is reliable, such as pressure, reserves, well number, well coordinate and other parameters. Since it is difficult to accurately obtain the static and production dynamic parameters of the non-cooperative party's work area, the data obtained from the non-cooperative party's work area is correctable, such as pressure, reserves, well number, well coordinate, cumulative gas production, single well production dynamic data and the like of the non-cooperative party's work area;

[0138] S4, carry out the history matching of the gas reservoir numerical model, and use the data according to the type and reliability level, correct the unreliable data and model parameters, and match the remaining geological reserves of the party's work area A before production under the influence of the non-cooperative party's work area B development in the numerical model, which is 245.6 billion cubic meters, which is basically consistent with the remaining geological reserves of the party's work area under the developed situation of the non-cooperative party's work area before production calculated by the volumetric method, thereby ensuring the reliability of the gas reservoir numerical model.

[0139] S5, use the corrected numerical model to carry out multi-scenario numerical simulation prediction. Since the development of the non-cooperative party's work area will deplete the geological reserves of the party's work area, the numerical simulation needs to consider the production of the adjacent area. A total of 20 simulation schemes are designed to carry out the party's work area gas production rate of 4.5%, 5.5%, 6.5%, 7.5% and 8.5%, and the corresponding production scale and single well allocation under the combination of multi-scenario numerical simulation with the non-cooperative party's work area gas production rate of 5.5%, 6.5%, 7.5% and 8.5%, and the corresponding production scale and single well allocation, to obtain the stable production period and cumulative gas production of the party's work area at the end of the 20-year prediction period.

[0140] Step four: carry out quantitative analysis oriented by benefit to determine the optimal development index

[0141] S1, establish the relationship curve between the internal rate of return of the party's work area and the gas production rate, as shown in Figure 3

[0142] S2, analysis found that the gas production rate of the gas reservoir is not positively correlated with the internal rate of return, showing an asymmetric parabolic relationship. With the increase of the production rate, the internal rate of return gradually increases, and when the production rate increases to a certain extent, the internal rate of return begins to decrease. 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 is increased, and the payback period is increased, 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. Through Figure 3 , the gas production rate interval of 5% to 7% of the party's work area with higher internal rate of return is screened;

[0143] S3, calculate the loss and regret expected value of the internal rate of return of the party's work area under different situations and different production rates, as shown in Figure 4 ​The results show that the expected value of internal rate of return in the study area increases first and then decreases with the increase of gas production rate, the expected value of regret value decreases first and then increases, the maximum expected value and the minimum regret value of the gas production rate interval coincide, the gas production rate interval with the minimum regret value / expected value is 5.5% to 6.5%, and the development risk is minimum.

[0144] S4, the internal rate of return and the quantitative analysis results of development risk are comprehensively analyzed, as shown in Figure 5 The gas production rate of the study area should be between 5.5% and 6.5%, the internal rate of return index is better, and the development risk is smaller.

[0145] As shown in Figure 6 As shown in The computer device provided by the embodiment of the present application, the device in the specification can be the computer device in the embodiment, and the computer device 602 can execute the method of the specification. The computer device 602 can include one or more processors 604, such as one or more central processing units (CPUs), and each processing unit can implement one or more hardware threads. The computer device 602 can also include any memory 606 for storing any kind of information such as code, settings, data, etc. Without limitation, for example, the memory 606 can include any one or a combination of the following: any type of RAM, any type of ROM, a flash memory device, a hard disk, an optical disk, etc. More generally, any memory can store information using any technology. Further, any memory can provide volatile or non-volatile retention of information. Further, any memory can represent a fixed or removable component of the computer device 602. In one case, the computer device 602 can perform any operation of the associated instructions when the processor 604 executes the associated instructions stored in any memory or combination of memories. 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 can 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). One specific output mechanism can 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 devices 612, and the output devices 614 can also not be included, just as a computer device in a network. The computer device 602 can 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 above-described components together.

[0147] The communication links 622 can be implemented in any manner, such as 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 links 622 can include any combination of hardwired links, wireless links, routers, gateway functionality, 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, which stores a computer program, and the computer program is executed by a processor to implement the method described above.

[0149] The embodiments of the present specification also provide a computer readable instruction, wherein when the processor executes the instruction, the program in the instruction makes the processor execute the method described above.

[0150] It should be understood that, in various embodiments of the embodiments of the present specification, the size of the sequence number of each process described above does not mean the order of execution, and the execution order of each process should be determined according to its function and inherent 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 the present specification, the term "and / or" is only to describe the association relationship of the associated objects, which means that there can be three relationships. For example, A and / or B can represent the following three cases: A exists alone, A and B exist together, and B exists alone. In addition, the character " / " in the embodiments of the present specification generally represents that the front and rear associated objects have an "or" relationship.

[0152] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed in the embodiments of the present specification can be realized in electronic hardware, computer software or a combination of both. In order to clearly illustrate the interchangeability of hardware and software, the components and steps of each example have been described in the above description in a general manner. Whether the functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. A person skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the embodiments of the present specification.

[0153] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the system, device and unit described above can refer to the corresponding process in the foregoing method embodiments, which will not be described here.

[0154] In several embodiments provided in the present specification, it should be understood that the disclosed system, device and method can be implemented in other manners. For example, the described device embodiments are merely schematic. The division of the units is merely a logical function division. There can be another division manner for the actual implementation, for example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections can be indirect couplings or communication connections through some interfaces, devices or units, and can be electric, mechanical or other forms.

[0155] The units described as separated components can or can not be physically separated, and the components displayed as units can or can not be physical units, i.e., can be located in one place, or can be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purposes of the embodiments of the present specification.

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

[0157] When 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 such an understanding, the technical solutions of the embodiments of the present specification essentially, or the part that contributes to the prior art, or all or a part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present specification. The foregoing storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk, and various other media that can store program codes.

[0158] The principles and implementation manners of the embodiments of the present specification are described by using specific examples in the embodiments of the present specification. The above example is only used to help understand the method and its core idea of the embodiments of the present specification. Meanwhile, for those skilled in the art, according to the idea of the embodiments of the present specification, the specific implementation manners and application ranges will be changed. In conclusion, the content of the present specification should not be understood as a limitation of the embodiments of the present specification.

Claims

1. A method for optimizing gas production rates in a gas reservoir with competitive production, the method comprising: The method comprises: acquiring the remaining geological reserves of the gas reservoir before the first work area is put into production; the first work area is a work area of a party; determining a first development index of the first work area based on the remaining geological reserves, and predicting a second development index of a second work area; the second work area is a work area of a non-cooperative party; establishing a numerical model of the gas reservoir to predict a first development result of the first work area at the end of the development under a development index and the development of the second work area under a second development index; 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, specifically comprising: establishing a relationship curve between the internal rate of return of the first work area and the first simulated gas production rate, and screening a gas production rate interval 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 under the second simulated gas production rate; and optimizing the initial gas production rate of the first work area based on the gas production rate interval and the development risk value.

2. The method of claim 1, wherein, Acquiring the remaining geological reserves of the gas reservoir before the first work area is put into production comprises: acquiring the geological parameters of the first work area; the geological parameters include: pre-production formation pressure, underground natural gas volume coefficient under pre-production formation pressure, gas-bearing area, reservoir effective thickness, effective porosity, and original gas saturation parameter; calculating the remaining geological reserves G of the gas reservoir before the first work area is put into production under the developed situation of the second work area based on the following formula: G = 0.01 × Ag × h × φ × Sg × (1 / Bg) wherein Ag is the gas-bearing area, h is the reservoir effective thickness, Φ is the effective porosity, Sg is the original gas saturation parameter, and Bg is the natural gas volume coefficient under the pre-production formation pressure.

3. The method of claim 1, wherein, Determining the first development index of the first work area based on the remaining geological reserves comprises: determining the maximum gas production scale and the initial gas production scale of the first work area based on the remaining geological reserves of the gas reservoir before the first work area is put into production; determining the number of first production wells that can be deployed in the first work area in combination with the reservoir distribution plane obtained by seismic prediction; determining the maximum gas production rate and the minimum gas production rate that can be reached in the first work area based on the remaining geological reserves of the gas reservoir before the first work area is put into production and the characteristics of the gas reservoir; acquiring a plurality of first simulated gas production rates based on the maximum gas production rate and the minimum gas production rate, and determining the corresponding single-well average production of a plurality of first production wells in the first work area under a plurality of different first simulated gas production rates according to the number of first production wells.

4. The method of claim 1, wherein, Predicting the second development index of the second work area comprises: determining the current gas production rate of the second work area and evaluating the pre-gas production rate; wherein the current gas production rate of the second work area is the gas production rate of the second work area after development 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; acquiring a plurality of second simulated gas production rates based on the current gas production rate and the pre-gas production rate, and determining different gas production scales of the second work area under a plurality of different second simulated gas production rates; According to the number of deployable second production wells in the second work area, a single well average production allocation under a current gas production rate and well average production allocations under a plurality of different second simulated gas production rates are determined.

5. The method of claim 1, wherein, The method for establishing a gas reservoir numerical model comprises: A gas reservoir original geological model is established, and a gas reservoir original geological reserve is fitted; the gas reservoir original geological model comprises a first work area model and a second work area model, and the gas reservoir original geological reserve is a sum of a first work area original geological reserve and a second work area original geological reserve; The gas reservoir original geological model is converted into a gas reservoir numerical model, and existing production data of the second work area are used to perform existing gas well production history fitting.

6. The method of claim 5, wherein, The method further comprises: Based on the gas reservoir numerical model, a prediction simulation value is predicted; the prediction simulation value is a first development result of the first work area at the end of a prediction period, which is predicted based on a first development index of the first work area and a second development index of the second work area when the first work area and the second work area are simultaneously developed; the first development result is a first work area cumulative gas production and a stable production period at the end of the prediction period.

7. A device for optimizing gas production rates in a competitive gas reservoir, characterized by The device comprises: A first acquisition unit is configured to acquire a remaining geological reserve of a gas reservoir before production of a first work area; the first work area is a first party work area; A second acquisition unit is configured to determine a first development index of the first work area based on the remaining geological reserve, and predict a second development index of a second work area; the second work area is a non-cooperation party work area; A model establishment unit is configured to establish a gas reservoir numerical model to predict a first development result of the first work area at the end of a prediction 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; An optimization unit is configured to optimize an initial gas production rate of the first work area based on the first development result, a first simulated gas production rate and a second simulated gas production rate, and specifically comprises: establishing a relationship curve between an internal rate of return of the first work area and the first simulated gas production rate, and screening a gas production rate interval 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 under the second simulated gas production rate; and optimizing the initial gas production rate of the first work area based on the gas production rate interval and the development risk value.

8. A computer device comprising a memory, a processor, and a computer program stored on the memory, wherein, The processor executes the computer program to implement the method of any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, The computer readable storage medium stores a computer program, and the computer program is executed by the processor to implement the method of any one of claims 1 to 6.

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