Method and apparatus for increasing the size of a computational work gas as a result of increasing the upper pressure limit

Abstract

The application provides a method and device for calculating the working gas amount of an underground gas storage which is increased due to an increase in the upper limit pressure, the method comprising: splitting the underground gas storage into a plurality of gas storage units with each gas injection well as the center of each gas storage unit; simulating the operation of each gas injection well in each gas storage unit to obtain the bottom hole pressure resistance value of each gas injection well; determining the stratum radius influenced by each gas injection well in each gas storage unit according to the bottom hole pressure resistance value of each gas injection well, the operation parameters of the underground gas storage and the target upper limit pressure of the underground gas storage; determining the increased working gas amount of each gas storage unit and the increased working gas amount of the underground gas storage according to the stratum radius and the target upper limit pressure. By splitting into the gas storage units with the gas injection well as the center, the stratum radius influenced by each gas injection well is determined independently, the problem of pressure imbalance does not need to be solved, and the working gas amount of the underground gas storage which is increased due to an increase in the upper limit pressure can be accurately determined.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of natural gas underground storage and reserves exploitation, and particularly relates to a method and device for calculating the scale of working gas increased due to the increase of upper limit pressure. BACKGROUND

[0002] The actual working gas volume of the natural gas underground storage currently in use is far lower than the designed working gas volume. In order to further increase the working gas volume, the upper limit pressure of the natural gas underground storage can be increased. However, how to accurately determine the gas volume range of the working gas volume of the active storage increased due to the increase of the upper limit pressure is a technical problem puzzling the technical personnel in the field.

[0003] The current calculation method for increasing the working gas volume of the active storage is based on the traditional whole gas layer pressure drop method. The basic idea is to consider the whole gas storage formation as a whole pressure drop. This whole pressure drop method needs the numerical value after the pressure field balance as the calculation basis. However, in the storage which has been built and is running, the pressure field is often difficult to truly balance. Because the storage repeatedly injects and produces gas through numerous production wells, the well bottom pressure is higher than the surrounding pressure to form a pressure rise funnel. Moreover, the balance period of the injection-production conversion is particularly short, the pressure rise funnel cannot fully expand to the boundary of the gas storage layer, causing the pressure imbalance phenomenon of high well bottom pressure and low surrounding pressure. At this time, the average pressure of the reservoir is difficult to determine.

[0004] It can be seen that the current method for calculating the scale of the working gas increased due to the increase of the upper limit pressure considers the gas storage formation as a whole pressure drop, and then needs the pressure data after the complete balance of the pressure field of the gas storage formation. However, the cyclic injection and production of the field cannot achieve the balance of the pressure field, which makes it difficult to accurately determine the gas volume of the working gas volume of the underground storage increased due to the increase of the upper limit pressure. SUMMARY

[0005] The embodiment of the present application provides a method for calculating the scale of the working gas increased due to the increase of the upper limit pressure, which is used to accurately determine the gas volume of the working gas volume of the underground storage increased due to the increase of the upper limit pressure. The method comprises the following steps:

[0006] The underground storage is split into multiple gas storage units with each gas injection well as the center of each gas storage unit;

[0007] In each gas storage unit, the operation of each gas injection well is simulated to obtain the well bottom pressure resistance value of each gas injection well;

[0008] According to the well bottom pressure resistance value of each gas injection well, the operation parameters of the underground storage and the target upper limit pressure of the underground storage, the stratum radius influenced by each gas injection well in each gas storage unit is determined;

[0009] determine the increased working gas volume of each gas storage unit according to the increased working gas volume of each gas storage unit;

[0010] determine the increased working gas volume of the underground gas storage according to the increased working gas volume of each gas storage unit.

[0011] The embodiment of the present application further provides a device for calculating the increased scale of working gas due to the increase of the upper limit pressure, which is used for accurately determining the increased gas storage volume of the working gas of the underground gas storage due to the increase of the upper limit pressure, and the device comprises:

[0012] a gas storage unit splitting module, which is used for splitting the underground gas storage into a plurality of gas storage units with each gas injection well as the center of each gas storage unit;

[0013] a gas injection well wellbore simulation module, which is used for simulating the operation of each gas injection well in each gas storage unit to obtain a bottom hole pressure bearing value of each gas injection well;

[0014] a formation radius determination module, which is used for determining the formation radius influenced by each gas injection well in each gas storage unit according to the bottom hole pressure bearing value of each gas injection well, the operation parameters of the underground gas storage and the target upper limit pressure of the underground gas storage;

[0015] a gas storage unit working gas volume determination module, which is used for determining the increased working gas volume of each gas storage unit according to the formation radius and the target upper limit pressure of the underground gas storage;

[0016] a working gas volume accumulation module, which is used for determining the increased working gas volume of the underground gas storage according to the increased working gas volume of each gas storage unit.

[0017] In the embodiment of the present application, the underground gas storage is split into multiple gas storage units with each gas injection well as the center of each gas storage unit; in each gas storage unit, the operation of each gas injection well is simulated to obtain the bottom hole pressure resistance value of each gas injection well; according to the bottom hole pressure resistance value of each gas injection well, the underground gas storage operation parameters and the target upper limit pressure of the underground gas storage, the stratum radius influenced by each gas injection well in each gas storage unit is determined; according to the stratum radius and the target upper limit pressure of the underground gas storage, the increased working gas amount of each gas storage unit is determined, and according to the increased working gas amount of each gas storage unit, the increased working gas amount of the underground gas storage is determined. By splitting the underground gas storage into separate gas storage units with gas injection wells as the center, the stratum radius influenced by each gas injection well is determined independently, the increased working gas amount of each gas storage unit is determined according to the stratum radius influenced by each gas injection well, and then the increased working gas amount of the underground gas storage is obtained according to the increased working gas amount of each gas storage unit. Compared with the prior art which takes the entire reservoir of the underground gas storage as the calculation unit, the increased working gas amount of the underground gas storage can be determined without solving the problem of pressure imbalance, so that the working gas amount of the underground gas storage which is increased due to the increase of the upper limit pressure can be accurately determined. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0019] Figure 1 The schematic diagram of the method for calculating the increased scale of the working gas due to the increase of the upper limit pressure in the embodiment of the present application.

[0020] Figure 2 The schematic diagram of the implementation method of step 102 in the specific embodiment of the present application.

[0021] Figure 3 The schematic diagram of the implementation method of step 202 in the specific embodiment of the present application.

[0022] Figure 4 The schematic diagram of the application implementation process of the specific embodiment of the present application.

[0023] Figure 5 The schematic diagram of the device for calculating the increased scale of the working gas due to the increase of the upper limit pressure in the embodiment of the present application.

[0024] Figure 6 The structural schematic diagram of the gas injection well wellbore simulation module 502 in the specific embodiment of the present application. DETAILED DESCRIPTION

[0025] With reference to the accompanying drawings: the technical solutions in the embodiments of the present application will be described clearly and completely, obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of the present application.

[0026] The embodiments of the present application provide a method for calculating the working gas amount increased due to the increase of the upper limit pressure, which is used to accurately determine the working gas amount of the underground gas storage increased due to the increase of the upper limit pressure, as shown in the formula: Figure 1 The method comprises the following steps:

[0027] Step 101: the underground gas storage is divided into multiple gas storage units with each gas injection well as the center of each gas storage unit;

[0028] Step 102: the operation of each gas injection well is simulated in each gas storage unit to obtain the bottom hole pressure value of each gas injection well;

[0029] Step 103: the stratum radius influenced by each gas injection well in each gas storage unit is determined according to the bottom hole pressure value of each gas injection well, the operation parameters of the underground gas storage and the target upper limit pressure of the underground gas storage;

[0030] Step 104: the working gas amount increased in each gas storage unit is determined according to the above stratum radius and the target upper limit pressure of the underground gas storage;

[0031] Step 105: the working gas amount of the underground gas storage increased is determined according to the working gas amount increased in each gas storage unit.

[0032] According to the method provided by the embodiments of the present application, the working gas amount of the underground gas storage increased due to the increase of the upper limit pressure can be accurately determined, and the working gas amount of the underground gas storage increased due to the increase of the upper limit pressure can be calculated. Figure 1As shown in the flow, in the embodiment of the present application, the underground gas storage is split into multiple gas storage units by taking each gas injection well as the center of each gas storage unit; in each gas storage unit, the operation of each gas injection well is simulated to obtain the bottom hole pressure value of each gas injection well; according to the bottom hole pressure value of each gas injection well, the underground gas storage operation parameter and the target upper limit pressure of the underground gas storage, the stratum radius influenced by each gas injection well in each gas storage unit is determined; according to the stratum radius and the target upper limit pressure of the underground gas storage, the increased working gas amount of each gas storage unit is determined, and according to the increased working gas amount of each gas storage unit, the increased working gas amount of the underground gas storage is determined. By splitting the underground gas storage into separate gas storage units with the gas injection well as the center, the stratum radius influenced by each gas injection well is determined independently, the increased working gas amount of each gas storage unit is determined according to the stratum radius influenced by each gas injection well, and then the increased working gas amount of the underground gas storage is obtained according to the increased working gas amount of each gas storage unit. Compared with the prior art which takes the entire reservoir of the underground gas storage as the calculation unit, the increased working gas amount of the underground gas storage can be determined without solving the problem of pressure imbalance, so that the working gas amount of the underground gas storage which is increased due to the increase of the upper limit pressure can be accurately determined.

[0033] In specific implementation, first, the underground gas storage is split into multiple gas storage units by taking each gas injection well as the center of each gas storage unit. When the upper limit pressure of the underground gas storage is increased, the gas storage stratum of the underground gas storage is considered as a whole pressure drop, the bottom hole pressure is higher than the surrounding pressure to form a pressure rise funnel during gas injection, and the balance period of injection-production conversion is particularly short, so the pressure rise funnel cannot fully expand to the boundary of the gas storage stratum, causing the phenomenon of pressure imbalance of high bottom hole pressure and low surrounding pressure, thereby making it difficult to determine the average pressure of the reservoir. Therefore, in the embodiment of the present application, the underground gas storage is split into multiple gas storage units, and each gas storage unit takes a gas injection well as the center.

[0034] After the underground gas storage is split into multiple gas storage units, in each gas storage unit, the operation of each gas injection well is simulated to obtain the bottom hole pressure value of each gas injection well. In specific implementation process, as shown in the figure, it includes: Figure 2

[0035] Step 201: In each gas storage unit, a wellbore model of each gas injection well is constructed, high pressure is formed by injecting gas into the gas storage layer at the bottom of the wellbore model, the injection pressure is increased according to a preset amplitude, and the gas leakage amount of the overlying stratum at the top of the wellbore model is recorded.

[0036] Step 202: According to the injection pressure and the gas leakage amount of the overlying stratum at the top of the wellbore model, the bottom hole pressure value of each gas injection well is determined.

[0037] ​In step 201, based on the actual geological stratification obtained from drilling, the configuration relationships of the three sets of permeable layers above the gas reservoir and the interlayer lithology and thickness are clearly defined. Based on the actual geological stratification, separate formation models are created and superimposed according to their configuration relationships to form a geological model considering the gas reservoir and its overlying strata. Holes are drilled in the model to simulate well drilling, and appropriate cement is injected for sealing, simulating well cementing, thus forming a wellbore model for the gas injection well. Simulating the formation temperature and stress environment, high-pressure gas is injected at the bottom of the wellbore model (gas reservoir) to create pressure, and leakage is monitored at the top of the model (the third permeable layer). The pressure is increased in increments according to a preset range, such as 5% of the original pressure of the gas reservoir, until the injected high-pressure gas breaks through the wellbore model, and leakage is detected at the top of the model.

[0038] In step 202, a curve showing the relationship between injection pressure and monitored gas volume is plotted to determine the injection pressure before the leak was detected. This pressure is then used as the temporary bottom pressure withstand value of the injection well, i.e., the bottom pressure withstand value of the injection well. The specific implementation process is as follows: Figure 3 As shown, it includes:

[0039] Step 301: Based on the gas injection pressure and the gas leakage of the overlying formation at the top of the wellbore model, plot the relationship curve between the gas injection pressure and the gas leakage of the overlying formation at the top of the wellbore model;

[0040] Step 302: Based on the above relationship curve, determine the gas injection pressure when the gas leakage of the overlying formation at the top of the wellbore model is zero;

[0041] Step 303: Determine the bottom pressure of each gas injection well as the injection pressure when the leakage of the overlying formation at the top of the wellbore model is zero.

[0042] After obtaining the bottom-hole pressure resistance value of each injection well, the formation radius affected by each injection well within each gas storage unit is determined based on the bottom-hole pressure resistance value of each injection well, the operating parameters of the underground gas storage facility, and the target upper limit pressure of the underground gas storage facility. In a specific embodiment, the formation radius affected by each injection well within each gas storage unit is determined according to the following formula:

[0043]

[0044] Among them, R ein Represents the formation radius affected by each gas injection well, in meters (m).

[0045] P Pmax The pseudo-pressure value representing the target upper limit pressure of the underground gas storage facility, in MPa. 2 / (mPa.s);

[0046] P PwfinThe pseudo-pressure value, in MPa, represents the bottom hole pressure resistance of each gas injection well. 2 / (mPa.s);

[0047] P min The lower limit pressure of the underground gas storage facility, expressed in MPa;

[0048] P max The target upper limit pressure of the underground gas storage facility, in MPa;

[0049] P sc The pressure under standard conditions is taken as 0.101325 MPa; T sc The temperature under standard conditions is taken as 293K;

[0050] B g The volume coefficient representing the gas in the underground gas storage facility;

[0051] T represents the ground temperature of the underground gas storage facility, in K;

[0052] η represents the pressure conductivity coefficient of the underground gas storage formation;

[0053] t in The injection time for each injection well is represented in days (d).

[0054] r w Represents the wellbore radius of each gas injection well, in meters (m).

[0055] e represents the natural constant, with a value of 2.71828.

[0056] Using the above formula, after determining the formation radius affected by each injection well within each gas storage unit, the increased working gas volume for each gas storage unit is determined based on the formation radius and the target upper limit pressure of the underground gas storage. In practice, the increased working gas volume for each gas storage unit is calculated by substituting the formation radius and the target upper limit pressure of the underground gas storage into the traditional material balance equation. In a specific embodiment, the traditional material balance equation is:

[0057]

[0058] Wherein, G represents the increased working gas volume of each gas storage unit;

[0059] Represents the formation porosity of each injection well, as a decimal.

[0060] c t The compressibility coefficient of the formation rock for each injection well, 1 / MPa;

[0061] h represents the formation thickness of each injection well, in meters (m).

[0062] Bg a volume coefficient representing gas in the underground gas storage;

[0063] P min a lower limit pressure representing the underground gas storage, MPa;

[0064] P max a target upper limit pressure representing the underground gas storage, MPa;

[0065] R ein a radius of stratum affected by each gas injection well, m.

[0066] After the increased working gas volume of each gas storage unit is determined, the increased working gas volume of the underground gas storage is determined according to the increased working gas volume of each gas storage unit. In specific embodiments, the increased working gas volume of the underground gas storage can be obtained by adding the increased working gas volumes of multiple gas storage units in a cumulative manner.

[0067] A specific example is given below to illustrate how the increased working gas volume of the underground gas storage due to the increase of the upper limit pressure is determined. The example is applied to a specific gas storage, and the steps for determining the increased working gas volume due to the increase of the upper limit pressure are shown in Fig. 1, which include: Figure 4

[0068] 1) A wellbore model is made to simulate high-pressure gas injection at the bottom of the well, and the temporary and short-term pressure resistance value at the bottom of the well is tested.

[0069] The specific process is as follows: ① The configuration relationship of the lithology and thickness of the three sets of permeable layers and the interlayer above the gas storage layer is determined according to the actually drilled geological stratification. ② The stratum models are made respectively and are superimposed according to the configuration relationship to form a geological model considering the gas storage layer and its overlying strata. ③ Drilling is simulated in the model to form a wellbore model, and corresponding cement is injected to simulate cementing. ④ The stratum temperature and stress environment are simulated, high-pressure gas is injected at the bottom of the wellbore model (the gas storage layer), and the gas leakage at the top of the model (the third set of permeable layers) is monitored. ⑤ The injected high-pressure gas is increased by 5% of the original pressure of the gas storage layer until the injected high-pressure gas breaks through the wellbore model and gas leakage is monitored at the top of the model. ⑥ The relationship curve between the injected pressure and the monitored gas volume is drawn, and the injected pressure before the gas leakage is found, which is used as the temporary and short-term pressure resistance value at the bottom of the gas injection well.

[0070] 2) A mathematical formula for controlling the range of the gas storage stratum of the gas injection well is established, and the range of the stratum controlled and affected by the gas injection well is solved by using the pressure resistance value of step 1) and the increased upper limit pressure and other parameters.

[0071] ​The bottom hole pressure value is converted into a pseudo pressure form, the expected upper limit pressure of the gas storage is converted into a pseudo pressure form, other parameters are taken as the actual operation values of the gas storage, and are substituted into the gas injection well controlled gas storage stratum range mathematical formula established in the embodiment of the application, and a stratum radius controlled and affected by the gas injection well is obtained by using a mathematical graphic method.

[0072] The gas injection well controlled gas storage stratum range mathematical formula is:

[0073]

[0074] 3) The results of 2) and the upper and lower limit pressures are substituted into a conventional material balance equation, and a value of increased working gas of the gas injection well due to the increased upper limit pressure is obtained.

[0075] 4) The total scale of the increased working gas of the gas injection well due to the increased upper limit pressure is obtained. For each gas injection well, steps 1), 2) and 3) are repeated to obtain the value of the increased working gas of each well due to the increased upper limit pressure, and the values of the above-mentioned each well are accumulated to obtain the value of the increased working gas of the entire gas storage due to the increased upper limit pressure.

[0076] 5) The above-mentioned steps are programmed to obtain a method and device for calculating the scale of the increased working gas due to the increased upper limit pressure.

[0077] Through example calculation, the gas storage has not reached the design expectation for nearly 17 years, the upper limit pressure is increased by 2 MPa to increase the working gas, and according to the algorithm of the prior art, the working gas can be increased by 100 million cubic meters. The actual operation shows that the working gas is only increased by 80 million cubic meters, and the reason is that the bottom hole pressure is too high during actual gas injection and is forced to stop injection. The actual result is close to the value of 82 million cubic meters obtained by the method provided in the embodiment of the application, which confirms that the method for calculating the scale of the increased working gas due to the increased upper limit pressure provided in the embodiment of the application is relatively reliable.

[0078] In the embodiment of the application, when the scale of the increased working gas due to the increased upper limit pressure is calculated, the algorithm of regarding the gas storage stratum as a pressure drop unit is completely broken, the gas storage stratum is split into a gas storage unit centered on the gas injection well, and the pressure imbalance problem is skillfully handled and hidden by establishing a gas injection well controlled gas storage stratum range mathematical formula, a method for calculating the stratum range affected by each gas injection well and the value of the increased working gas of each well and the entire gas storage due to the increased upper limit pressure is obtained. The method has the following four advantages:

[0079] Firstly, the whole is divided into parts, and the pressure imbalance problem of the traditional method is greatly reduced by reducing the pressure field area.

[0080] Secondly, the gas injection well controlled gas storage stratum range mathematical formula is established to further eliminate the pressure imbalance problem in the control range of the gas injection well.

[0081] Thirdly, due to the elimination of the influence of pressure imbalance, the pressure recovery time of the conventional balancing period of the gas storage can be greatly reduced, so that the rapid injection-production conversion production demand is possible, and therefore the application range is larger than that of the conventional method.

[0082] Fourthly, in the mathematical formula for establishing the control gas injection well formation range in the embodiment of the present application, not only the upper limit pressure in the traditional method is included, but also the temporary pressure resistance value of the bottom hole pressure is fully considered to prevent the safety risk of bottom hole gas leakage, and the consideration factors are more comprehensive.

[0083] The above specific application implementation is only an example, and the remaining implementation modes will not be described one by one.

[0084] Based on the same inventive concept, the embodiment of the present application also provides a device for calculating the working gas scale increased due to the increase of the upper limit pressure, and since the principle of the problem solved by the device for calculating the working gas scale increased due to the increase of the upper limit pressure is similar to that of the method for calculating the working gas scale increased due to the increase of the upper limit pressure, the implementation of the device for calculating the working gas scale increased due to the increase of the upper limit pressure can be referred to the implementation of the method for calculating the working gas scale increased due to the increase of the upper limit pressure, and the repeated parts will not be described again, and the specific structure is as shown in Figure 5 .

[0085] The gas storage unit splitting module 501 is used to split the underground gas storage into multiple gas storage units with each gas injection well as the center of each gas storage unit;

[0086] The gas injection well wellbore simulation module 502 is used to simulate the operation of each gas injection well in each gas storage unit to obtain the bottom hole pressure resistance value of each gas injection well;

[0087] The formation radius determination module 503 is used to determine the formation radius affected by each gas injection well in each gas storage unit according to the bottom hole pressure resistance value of each gas injection well, the underground gas storage operation parameter and the target upper limit pressure of the underground gas storage;

[0088] The gas storage unit working gas amount determination module 504 is used to determine the increased working gas amount of each gas storage unit according to the above formation radius and the target upper limit pressure of the underground gas storage;

[0089] The working gas amount accumulation module 505 is used to determine the increased working gas amount of the underground gas storage according to the increased working gas amount of each gas storage unit.

[0090] In specific implementation, the structure of the gas injection well wellbore simulation module 502 is as shown in Figure 6 , and includes:

[0091] The simulation gas injection unit 601 is configured to construct a wellbore model of each gas injection well in each gas storage unit, form high pressure in the gas storage layer at the bottom of the wellbore model by injecting gas, increase the gas injection pressure according to a preset amplitude, and record the gas leakage amount of the overburden layer at the top of the wellbore model.

[0092] The well bottom pressure determination unit 602 is configured to determine the well bottom pressure value of each gas injection well according to the gas injection pressure and the gas leakage amount of the overburden layer at the top of the wellbore model.

[0093] In specific embodiments, the well bottom pressure determination unit 602 is specifically configured to:

[0094] draw a relationship curve of the gas injection pressure and the gas leakage amount of the overburden layer at the top of the wellbore model according to the gas injection pressure and the gas leakage amount of the overburden layer at the top of the wellbore model;

[0095] determine the gas injection pressure when the gas leakage amount of the overburden layer at the top of the wellbore model is zero according to the above relationship curve;

[0096] determine the gas injection pressure when the gas leakage amount of the overburden layer at the top of the wellbore model is zero as the well bottom pressure value of each gas injection well.

[0097] In specific embodiments, the formation radius determination module 503 is specifically configured to:

[0098] determine the formation radius affected by each gas injection well in each gas storage unit according to the well bottom pressure value of each gas injection well, the underground gas storage operation parameters, and the target upper limit pressure of the underground gas storage according to the following formula:

[0099]

[0100] wherein, R ein represents the formation radius affected by each gas injection well, m;

[0101] P Pmax represents the pseudo-pressure value of the target upper limit pressure of the underground gas storage, MPa 2 / (mPa·s);

[0102] P Pwfin represents the pseudo-pressure value of the well bottom pressure value of each gas injection well, MPa 2 / (mPa·s);

[0103] P min represents the lower limit pressure of the underground gas storage, MPa;

[0104] P max represents the target upper limit pressure of the underground gas storage, MPa;

[0105] P sc represents the pressure under standard conditions, which is 0.101 325 MPa; Tsc represents the temperature under standard conditions, and takes 293K;

[0106] B g represents the volume coefficient of the gas in the underground gas storage;

[0107] T represents the formation temperature of the underground gas storage, K;

[0108] η represents the pressure conductivity coefficient of the formation of the underground gas storage;

[0109] t in represents the gas injection time of each gas injection well, d;

[0110] r w represents the borehole radius of each gas injection well, m;

[0111] e represents a natural constant, and takes 2.71828.

[0112] The embodiment of the present application further provides a computer device, which comprises a memory, a processor and a computer program stored in the memory and capable of running on the processor, and the processor implements the above method for calculating the working gas scale increased due to the increase of the upper limit pressure when executing the computer program.

[0113] The embodiment of the present application further provides a computer readable storage medium, which stores a computer program for executing the above method for calculating the working gas scale increased due to the increase of the upper limit pressure.

[0114] In conclusion, the method and device for calculating the working gas scale increased due to the increase of the upper limit pressure provided by the embodiment of the present application have the following advantages:

[0115] The underground gas storage is split into multiple gas storage units by taking each gas injection well as the center of each gas storage unit; in each gas storage unit, the operation of each gas injection well is simulated to obtain the bottom hole pressure resistance value of each gas injection well; according to the bottom hole pressure resistance value of each gas injection well, the underground gas storage operation parameter and the target upper limit pressure of the underground gas storage, the stratum radius influenced by each gas injection well in each gas storage unit is determined; according to the stratum radius and the target upper limit pressure of the underground gas storage, the increased working gas amount of each gas storage unit is determined, and according to the increased working gas amount of each gas storage unit, the increased working gas amount of the underground gas storage is determined. By splitting the underground gas storage into separate gas storage units with the gas injection well as the center, the stratum radius influenced by each gas injection well is determined independently, the increased working gas amount of each gas storage unit is determined according to the stratum radius influenced by each gas injection well, and then the increased working gas amount of the underground gas storage is obtained according to the increased working gas amount of each gas storage unit. Compared with the prior art which takes the entire reservoir of the underground gas storage as a calculation unit, the increased working gas amount of the underground gas storage can be determined without solving the problem of pressure imbalance, so that the working gas amount of the underground gas storage which is increased due to the increase of the upper limit pressure can be accurately determined.

[0116] Those skilled in the art will appreciate that embodiments of the application can be supplied as methods, apparatus, or computer program products. Accordingly, the application can be embodied in the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the application can be embodied in the form of a computer program product on one or more computer readable storage media (including, but not limited to, disk memory, CD-ROMs, optical storage media, etc.) having computer usable program code embodied thereon.

[0117] The present application is described in reference to the flowchart and / or block diagram of the method, apparatus and computer program product according to the embodiments of the present application. It should be understood that each flow and / or block in the flowchart and / or block diagram, and the combination of flows and / or blocks in the flowchart and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general purpose computer, a special purpose computer, an embedded processor, or other programmable data processing apparatus to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing apparatus produce the functions specified in the flowchart and / or block diagram block or blocks. Figure 1 The function specified in one flow or multiple flows and / or blocks Figure 1 The apparatus for performing the function specified in one flow or multiple flows and / or blocks.

[0118] These computer program instructions can also be stored in a computer readable storage medium that can direct the computer or other programmable data processing apparatus to work in a specific manner, so that the instructions stored in the computer readable storage medium produce the manufacture including the instruction apparatus, which implements the functions specified in the flowchart and / or block diagram block or blocks. Figure 1one or more processes and / or blocks Figure 1 the function specified in the one or more blocks.

[0119] These computer program instructions can also be loaded into computer or other programmable data processing devices, so that a series of operational steps are performed on the computer or other programmable data processing devices to generate computer-implemented processes, so that the instructions executed on the computer or other programmable data processing devices provide processes for implementing the flow Figure 1 one or more processes and / or blocks Figure 1 the function specified in the one or more blocks.

[0120] The above only the preferred embodiments of the present application, and not for limiting the present application, for those skilled in the art, the present application can have various alterations and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application, should be included in the scope of protection of the present application.

Claims

1. A method for calculating the increase in the scale of working gas due to an increase in the upper limit pressure, characterized in that, include: The underground gas storage facility is divided into multiple gas storage units, with each injection well serving as the center of each gas storage unit; Within each gas storage unit, the operation of each injection well is simulated to obtain the bottom pressure resistance value of each injection well; Based on the bottom pressure resistance value of each injection well, the operating parameters of the underground gas storage facility, and the target upper limit pressure of the underground gas storage facility, the formation radius affected by each injection well within each gas storage unit is determined. Based on the aforementioned stratum radius and the target upper limit pressure of the underground gas storage, determine the additional working gas volume for each gas storage unit; The increase in working gas volume for the underground gas storage facility is determined based on the increase in working gas volume for each gas storage unit. Within each gas storage unit, the operation of each injection well is simulated to obtain the bottom hole pressure resistance value of each injection well. This includes: constructing a wellbore model for each injection well within each gas storage unit; injecting gas into the gas storage layer at the bottom of the wellbore model to form high pressure; increasing the injection pressure according to a preset range; and recording the leakage of gas from the overlying formation at the top of the wellbore model. Based on the injection pressure and the leakage of gas from the overlying formation at the top of the wellbore model, the bottom hole pressure resistance value of each injection well is determined. Based on the gas injection pressure and the leakage of the overlying formation at the top of the wellbore model, the bottom hole pressure resistance value of each gas injection well is determined, including: plotting the relationship curve between the gas injection pressure and the leakage of the overlying formation at the top of the wellbore model; determining the gas injection pressure when the leakage of the overlying formation at the top of the wellbore model is zero based on the relationship curve; and determining the gas injection pressure when the leakage of the overlying formation at the top of the wellbore model is zero as the bottom hole pressure resistance value of each gas injection well. The formation radius affected by each injection well within each gas storage unit is determined according to the following formula, based on the bottom-hole pressure resistance value of each injection well, the operating parameters of the underground gas storage, and the target upper limit pressure of the underground gas storage: Among them, R ein Represents the formation radius affected by each gas injection well; P Pmax The pseudo-pressure value representing the target upper limit pressure of the underground gas storage facility; P Pwfin The simulated pressure value representing the bottom hole pressure resistance of each gas injection well; P min This represents the lower limit pressure of an underground gas storage facility. P max The target upper limit pressure for underground gas storage facilities; P sc T represents the pressure under standard conditions. sc Represents the temperature under standard conditions; B g The volume coefficient representing the gas in the underground gas storage facility; T represents the ground temperature of the underground gas storage facility; η represents the pressure conductivity coefficient of the underground gas storage formation; t in This represents the injection time for each injection well; r w This represents the wellbore radius of each gas injection well; e represents the natural constant, with a value of 2.71828.

2. A device for calculating the increase in the scale of working gas due to an increase in the upper limit pressure, characterized in that, include: The gas storage unit splitting module is used to divide the underground gas storage facility into multiple gas storage units, with each injection well as the center of each gas storage unit; The wellbore simulation module for gas injection wells is used to simulate the operation of each gas injection well within each gas storage unit and obtain the bottom pressure resistance value of each gas injection well. The formation radius determination module is used to determine the formation radius affected by each gas injection well in each gas storage unit based on the bottom pressure resistance value of each gas injection well, the operating parameters of the underground gas storage, and the target upper limit pressure of the underground gas storage. The gas storage unit working gas volume determination module is used to determine the additional working gas volume for each gas storage unit based on the formation radius and the target upper limit pressure of the underground gas storage. The working gas volume accumulation module is used to determine the increase in working gas volume of the underground gas storage based on the increase in working gas volume of each gas storage unit. The gas injection wellbore simulation module includes: The simulated gas injection unit is used to construct a wellbore model for each gas injection well within each gas storage unit. Gas is injected into the gas storage layer at the bottom of the wellbore model to form high pressure. The gas injection pressure is increased according to a preset range, and the leakage of gas in the overlying formation at the top of the wellbore model is recorded. The bottom-hole pressure resistance determination unit is used to determine the bottom-hole pressure resistance value of each gas injection well based on the gas injection pressure and the gas leakage of the overlying formation at the top of the wellbore model. The bottom-hole pressure resistance determination unit is specifically used for: plotting a relationship curve between the gas injection pressure and the leakage of the overlying formation at the top of the wellbore model, based on the gas injection pressure and the leakage of the overlying formation at the top of the wellbore model; determining the gas injection pressure when the leakage of the overlying formation at the top of the wellbore model is zero, based on the relationship curve; and determining the gas injection pressure when the leakage of the overlying formation at the top of the wellbore model is zero as the bottom-hole pressure resistance value for each gas injection well. The formation radius determination module is specifically used for: The formation radius affected by each injection well within each gas storage unit is determined using the following formula, based on the bottom-hole pressure resistance value of each injection well, the operating parameters of the underground gas storage facility, and the target upper limit pressure of the underground gas storage facility: Among them, R ein Represents the formation radius affected by each gas injection well; P Pmax The pseudo-pressure value representing the target upper limit pressure of the underground gas storage facility; P Pwfin The simulated pressure value representing the bottom hole pressure resistance of each gas injection well; P min This represents the lower limit pressure of an underground gas storage facility. P max The target upper limit pressure for underground gas storage facilities; P sc T represents the pressure under standard conditions. sc Represents the temperature under standard conditions; B g The volume coefficient representing the gas in the underground gas storage facility; T represents the ground temperature of the underground gas storage facility; η represents the pressure conductivity coefficient of the underground gas storage formation; t in This represents the injection time for each injection well; r w This represents the wellbore radius of each gas injection well; e represents the natural constant, with a value of 2.71828.

3. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method of claim 1.

4. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method of claim 1.

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