Method and device for determining effective inventory of low-permeability gas reservoir type gas storage

Abstract

The invention discloses a method and a device for determining effective inventory of a low-permeability gas reservoir type gas storage. The method comprises the steps that according to injection-production operation characteristics of the low-permeability gas storage, the gas storage is divided into a core injection-production area and a peripheral linkage area; determining a first control inventory of the core injection-production area in the target injection-production period based on the obtained first formation pressure; on the basis of the first control stock amount, the gas storage volume and the second control stock amount of the peripheral linkage area are obtained; based on the gas storage volume and a second control stock amount, second formation pressure of the peripheral linkage area is determined; based on the first formation pressure, the second formation pressure, the first control stock and the second control stock, the average formation pressure in the target injection-production period of the gas storage is determined; and on the basis of the average formation pressure and in combination with the obtained gas production amount in the target injection-production period, the effective stock amount of the gas storage before gas production in the target injection-production period is determined. The method can accurately solve the problem of how to evaluate the inventory of the low-permeability gas reservoir type gas storage.

Description

Technical Field

[0001] The present invention relates to the technical field of underground gas storage construction and operation, and in particular to a method and device for determining the effective inventory of a low-permeability gas reservoir type gas storage. Background Art

[0002] Gas storage generally refers to the use of existing underground storage space. Natural gas is injected into the gas storage for storage during the off-season and quickly taken out during the peak season, which plays an important regulatory role in achieving a balance between natural gas supply and demand. During the use of gas storage, the evaluation of formation pressure before and after injection and production is an important task and an important basis for evaluating parameters such as effective inventory and injection and production capacity of the gas storage. When evaluating the relevant parameters of the gas storage using the formation pressure before and after injection and production of the gas storage, the formation pressure is obtained through bottom hole testing, and the formation pressure obtained by the bottom hole test is used as the formation pressure of the gas storage to evaluate the effective inventory, injection and production capacity and other parameters of the gas storage. Summary of the invention

[0003] For low-permeability gas reservoir-type gas storage, since the formation pressure cannot reach equilibrium in a short time after injection and production, the formation pressure measured by bottom hole testing cannot fully represent the actual formation pressure of the low-permeability gas reservoir gas storage. Therefore, when using formation pressure to determine the effective inventory, injection and production capacity and other parameters of the low-permeability gas storage, there is a certain deviation between the results of the effective inventory and the actual value.

[0004] In view of the above problems, the present invention is proposed to provide a method and device for determining the effective inventory of a low-permeability gas reservoir type gas storage facility that overcomes the above problems or at least partially solves the above problems.

[0005] The embodiment of the present invention provides a method for determining the effective inventory of a low-permeability gas reservoir type gas storage, comprising:

[0006] According to the injection and production operation characteristics of the low-permeability gas storage reservoir, the gas storage reservoir is divided into a core injection and production area and a peripheral linkage area; the core injection and production area refers to the area that can be affected by pressure conduction when the formation pressure recovers to a stable pressure within the well-closing balance time during the shut-in balance stage of the injection and production wells of the low-permeability gas storage reservoir; the peripheral linkage area refers to the area outside the core injection and production area when the formation pressure recovers to a stable pressure within the well-closing balance time during the injection and production wells of the low-permeability gas storage reservoir;

[0007] Acquiring a first formation pressure of a core injection-production area within a target injection-production cycle, and determining a first controlled inventory volume of the core injection-production area within the target injection-production cycle based on the first formation pressure;

[0008] Based on the first controlled inventory volume in the target injection-production cycle, the gas storage volume of the peripheral linkage area and the second controlled inventory volume of the peripheral linkage area in the target injection-production cycle are obtained;

[0009] Determining a second formation pressure of the peripheral linkage zone within a target injection-production cycle based on the gas storage volume of the peripheral linkage zone and the second controlled inventory;

[0010] Determining an average formation pressure within a target injection-production cycle of the gas storage based on the first formation pressure, the second formation pressure, the first controlled inventory amount, and the second controlled inventory amount;

[0011] Based on the average formation pressure and in combination with the obtained gas production within the target injection-production cycle, the effective inventory volume of the gas storage before gas production within the target injection-production cycle is determined.

[0012] In an optional embodiment, the first controlled inventory includes: a first gas injection controlled inventory and a first gas production controlled inventory; the first formation pressure includes: a formation pressure before gas injection, a formation pressure before the first gas production, and a formation pressure after the first gas production;

[0013] Determining a first controlled inventory volume in a core injection-production area within a target injection-production period based on the first formation pressure includes:

[0014] Calculating the first gas injection control inventory based on the formation pressure before gas injection, the formation pressure before the first gas production, and the gas injection volume within the target injection-production cycle;

[0015] The first gas production control inventory is calculated based on the formation pressure before the first gas production, the formation pressure after the first gas production, and the gas production volume within the target injection and production cycle.

[0016] In an optional embodiment, the method for determining the effective inventory of a low-permeability gas reservoir type gas storage facility described in the embodiment of the present invention further includes:

[0017] Obtain the gas field production data in the early stage of the reservoir construction, and determine the original formation pressure and controlled dynamic reserves of the gas storage based on the gas field production data in the early stage of the reservoir construction;

[0018] Calculate the original gas storage volume of the gas storage based on the original formation pressure and controlled dynamic reserves of the gas storage;

[0019] Based on the remaining gas volume before gas storage construction in the gas field production data in the early stage of storage construction, as well as the total gas injection volume and total gas production volume before gas production in the target injection and production period of the gas storage, the pre-gas production inventory within the target injection and production period of the gas storage is calculated.

[0020] In an optional embodiment, the gas storage volume of the peripheral linkage zone includes: a second gas injection gas storage volume and a second gas extraction gas storage volume;

[0021] Based on the first controlled inventory within the target injection-production cycle, the gas storage volume of the peripheral linkage area within the target injection-production cycle is obtained, including:

[0022] Based on the first gas injection control inventory and the first formation pressure before gas production, a first gas injection storage volume of the core injection and production area is calculated;

[0023] Based on the first gas production control inventory and the first formation pressure before gas production, a first gas production storage volume of the core injection and production area is calculated;

[0024] Obtaining the second gas injection gas storage volume according to the difference between the original gas storage volume of the gas storage reservoir and the first gas injection gas storage volume;

[0025] The second gas collection and storage volume is obtained according to the difference between the original gas storage volume of the gas storage reservoir and the first gas collection and storage volume.

[0026] In an optional embodiment, the second control inventory of the peripheral linkage area includes: a second gas extraction control inventory and a second gas injection control inventory;

[0027] Based on the first controlled inventory quantity within the target injection-production cycle, the second controlled inventory quantity of the peripheral linkage area is calculated, including:

[0028] Obtaining the second gas injection control inventory amount according to the difference between the pre-gas production inventory amount and the first gas injection control inventory amount within the target injection and production cycle;

[0029] The second gas production control inventory is obtained according to the difference between the pre-gas production inventory and the first gas production control inventory within the target injection and production cycle.

[0030] In an optional embodiment, the second formation pressure includes: a second formation pressure before gas production and a second formation pressure after gas production;

[0031] Determining the second formation pressure of the peripheral linkage area within the target injection-production cycle based on the gas storage volume of the peripheral linkage area and the second controlled inventory; comprising:

[0032] The second formation pressure before gas production is calculated based on the second gas injection control inventory and the second gas injection storage volume in combination with the following formula;

[0033]

[0034] Where P wcq is the second gas production formation pressure in the peripheral linkage area, T is the formation temperature of the gas storage reservoir, Z wcq The formation pressure P of the gas stored in the peripheral linkage area before the second gas production wcq The coefficient of deviation under P sc is the pressure of the gas stored in the gas storage under standard conditions, T sc is the temperature of the gas stored in the gas storage under standard conditions, V wztjis the second gas injection storage volume in the peripheral linkage area, G wzkc Control inventory for the second gas injection in the peripheral linkage area;

[0035] The second gas production controlled inventory and the second gas production storage volume are used to calculate the second gas production formation pressure in combination with the following formula;

[0036]

[0037] Where P wch is the formation pressure after the second gas production in the peripheral linkage area, V wctj is the second gas production and storage volume of the peripheral linkage area, G wckc is the second gas production control inventory in the peripheral linkage area, Z wch The formation pressure P of the gas stored in the peripheral linkage area after gas extraction wch The coefficient of deviation below.

[0038] In an optional embodiment, determining the average formation pressure within the target injection-production cycle of the gas storage based on the first formation pressure, the second formation pressure, the first controlled inventory amount, and the second controlled inventory amount includes:

[0039] According to the first formation pressure before gas production and the second formation pressure before gas production, as well as the first gas injection control inventory and the second gas injection control inventory, and in combination with the following formula, the average formation pressure before gas production of the gas storage reservoir within the target injection and production period is calculated;

[0040]

[0041] Where P cq is the average formation pressure before gas production in the gas storage, P hcq is the formation pressure before the first gas production, G hzkc Control inventory levels for first gas injection;

[0042] According to the first gas production formation pressure and the second gas production formation pressure, as well as the first gas production control inventory and the second gas production control inventory, and in combination with the following formula, the average gas production formation pressure of the gas storage reservoir within the target injection and production period is calculated;

[0043]

[0044] Where P ch is the average formation pressure after gas production in the gas storage, G c is the gas production volume within the target injection-production cycle, P wch is the formation pressure after the first gas production, G hckc Control the inventory for the first gas production.

[0045] In an optional embodiment, the method for determining the effective inventory of a low-permeability gas reservoir type gas storage facility of the embodiment of the present invention further includes:

[0046] The utilization rate of the gas storage reservoir inventory is determined based on the effective inventory volume of the gas storage reservoir before gas extraction and the inventory volume before gas extraction.

[0047] Based on the same inventive concept, an embodiment of the present invention further provides a device for determining the effective inventory of a low-permeability gas reservoir type gas storage, comprising:

[0048] Area division module: used to divide the low permeability gas storage into a core injection and production area and a peripheral linkage area according to the injection and production operation characteristics of the low permeability gas storage; the core injection and production area refers to the area that can be affected by pressure conduction when the formation pressure recovers to a stable pressure during the shut-in balance period of the injection and production wells of the low permeability gas storage; the peripheral linkage area refers to the area outside the core injection and production area when the formation pressure recovers to a stable pressure during the shut-in balance period of the injection and production wells of the low permeability gas storage;

[0049] A first determination module: used to obtain a first formation pressure of a core injection-production area within a target injection-production period, and determine a first controlled inventory volume of the core injection-production area within the target injection-production period based on the first formation pressure;

[0050] A second determination module is used to obtain the gas storage volume of the peripheral linkage area within the target injection-production cycle and the second controlled inventory of the peripheral linkage area based on the first controlled inventory within the target injection-production cycle;

[0051] A third determination module is used to determine a second formation pressure of the peripheral linkage zone within a target injection-production cycle based on the gas storage volume of the peripheral linkage zone and the second controlled inventory;

[0052] a fourth determination module, configured to determine an average formation pressure within a target injection-production cycle of the gas storage reservoir based on the first formation pressure, the second formation pressure, the first controlled inventory amount, and the second controlled inventory amount;

[0053] The fifth determination module is used to determine the effective inventory of the gas storage reservoir within the target injection and production cycle based on the average formation pressure and the obtained gas production within the target injection and production cycle.

[0054] Based on the same inventive concept, an embodiment of the present invention also provides an effective inventory determination and analysis system for a low-permeability gas reservoir type gas storage facility, comprising a memory and a processor, wherein a computer program is stored on the memory, and when the computer program is executed by the processor, the effective inventory determination method for a low-permeability gas reservoir type gas storage facility as described above is implemented.

[0055] Based on the same inventive concept, an embodiment of the present invention further provides a storage medium having a computer program stored thereon. When the computer program is executed by a processor, the above-mentioned method for determining the effective inventory of a low-permeability gas reservoir type gas storage is implemented.

[0056] The beneficial effects of the above technical solution provided by the embodiment of the present invention include at least:

[0057] The method for determining the effective inventory of a low-permeability gas reservoir type gas storage provided by an embodiment of the present invention divides the gas storage into a core injection and production area and a peripheral linkage area according to the injection and production operation characteristics of the low-permeability gas storage, and determines the average formation pressure within the target injection and production cycle of the gas storage according to the first formation pressure of the core injection and production area within the target injection and production cycle and the second injection and production pressure of the peripheral linkage area, and uses the average formation pressure as the formation pressure of the low-permeability gas storage for pressure evaluation; that is, the method for determining the effective inventory provided by an embodiment of the present invention, when evaluating the pressure of the gas storage, not only takes into account the first formation pressure of the core injection and production area that can be obtained by bottom hole testing, but also takes into account the second formation pressure of the peripheral linkage area that cannot be measured. Compared with the existing method of determining the effective inventory of a low-permeability gas storage using only the first formation pressure, the technical problem that the effective inventory of the gas storage determined by the existing method has a large deviation from the actual one is effectively solved, and the injection and production seepage and inventory utilization characteristics of the low-permeability gas storage can be truly reflected.

[0058] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0059] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0061] Figure 1 It is a schematic flow chart of a method for determining the effective inventory of a low-permeability gas reservoir type gas storage facility in an embodiment of the present invention;

[0062] Figure 2 It is a schematic diagram of the structure of a device for determining the effective inventory of a low-permeability gas reservoir type gas storage in an embodiment of the present invention. DETAILED DESCRIPTION

[0063] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0064] The inventors of the present application discovered that, for low-permeability gas reservoir-type gas storage, since the formation pressure after injection and production cannot reach equilibrium in a relatively short period of time, the formation pressure measured by bottom hole testing cannot fully represent the actual formation pressure of the low-permeability gas reservoir-type gas storage. Therefore, when using the formation pressure to evaluate parameters such as the effective inventory volume and injection and production capacity of the low-permeability gas reservoir, there is a certain deviation between the results of the effective inventory volume and the actual value; and the methods for determining the effective inventory volume and inventory utilization rate of the gas storage in the prior art are not suitable for the evaluation of the effective inventory volume of the low-permeability gas reservoir-type gas storage.

[0065] For example: In the prior art, a patent application with publication number: CN108625823A discloses a method for determining the capacity of a gas storage reservoir, including the following steps: establishing a formation pressure model according to the real-time radius of the gas layer in the gas storage reservoir; establishing a bottom hole flow pressure model according to the effective permeability of the gas storage reservoir and the gas layer skin coefficient; establishing a wellhead oil pressure model and a gas injection model of the gas storage reservoir according to the formation pressure model and the bottom hole flow pressure model; and determining the capacity of the gas storage reservoir according to the wellhead oil pressure model and the gas injection model. Although this technical solution can accurately determine the storage capacity of the gas storage reservoir, and the storage capacity obtained according to this method can timely perform peak-shaving operations on gas wells, it is not suitable for all types of gas storage reservoirs, especially for gas reservoir-type gas storage reservoirs. There is a certain gap between the storage capacity value obtained by this method and the actual value, and the effect is not ideal.

[0066] The patent application with publication number CN113792426A discloses a method and device for determining the injectable and recoverable gas volume of an underground salt cavern gas storage. It includes: obtaining the first parameter of the wellbore, the second parameter of the salt cavity, and the injection and production operation parameters of the underground salt cavern gas storage; calculating the temperature and pressure parameters and gas physical property parameters of the underground salt cavern gas storage through simulation software based on the first parameter, the second parameter, and the injection and production operation parameters; determining the real-time gas storage volume and gas storage volume range of the underground salt cavern gas storage based on the temperature and pressure parameters and the gas physical property parameters; determining the injectable gas volume and recoverable gas volume of the underground salt cavern gas storage based on the real-time gas storage volume and the gas storage volume range. However, this patent application still cannot solve the problem of accurate calculation and evaluation of the effective inventory of gas reservoir-type gas storage, and the actual deviation value is relatively large.

[0067] In response to the problems encountered in the prior art, an embodiment of the present invention provides a method and device for determining the effective inventory of a low-permeability gas reservoir type gas storage facility; it should be noted that an injection-production cycle in the embodiment of the present invention includes: a gas injection process and a gas production process; the period before gas production specifically refers to the period after gas injection and before gas production within an injection-production cycle; the effective inventory within the injection-production cycle is the effective inventory within the injection-production cycle after gas injection and before gas production; the formation pressure after gas production specifically refers to the formation pressure after gas production balance.

[0068] The method for determining the effective inventory of a low permeability gas reservoir type gas storage provided by the embodiment of the present invention has a flow chart referring to Figure 1 As shown, including:

[0069] Step S101: according to the injection and production operation characteristics of the low permeability gas storage, the gas storage is divided into a core injection and production area and a peripheral linkage area; the core injection and production area refers to the area that can be affected by pressure conduction when the formation pressure recovers to a stable pressure within the well closing balance time during the shut-in balance stage of the injection and production wells of the low permeability gas storage; the peripheral linkage area refers to the area outside the core injection and production area when the formation pressure recovers to a stable pressure within the well closing balance time during the injection and production wells of the low permeability gas storage;

[0070] Step S102: obtaining a first formation pressure of a core injection-production area within a target injection-production cycle, and determining a first controlled inventory volume of the core injection-production area within the target injection-production cycle based on the first formation pressure;

[0071] Step S103: based on the first controlled inventory volume in the target injection-production cycle, obtaining the gas storage volume of the peripheral linkage area in the target injection-production cycle and the second controlled inventory volume of the peripheral linkage area;

[0072] Step S104: determining a second formation pressure of the peripheral linkage zone within a target injection-production cycle based on the gas storage volume of the peripheral linkage zone and the second controlled inventory;

[0073] Step S105: determining an average formation pressure within a target injection-production cycle of the gas storage based on the first formation pressure, the second formation pressure, the first controlled inventory level, and the second controlled inventory level;

[0074] Step S106: Based on the average formation pressure and in combination with the obtained gas production within the target injection-production cycle, determine the effective inventory volume of the gas storage before gas production within the target injection-production cycle.

[0075] For low-permeability gas reservoir-type gas storage, the formation pressure after injection and production cannot reach equilibrium in a relatively short period of time, which will lead to a large difference in formation pressure between the core injection and production area and the peripheral linkage area. In addition, since the first formation pressure of the core injection and production area can be obtained through bottom hole testing, while the second formation pressure of the peripheral linkage area cannot be obtained through bottom hole testing, it is often ignored. Therefore, when conducting formation evaluation on low-permeability gas reservoir-type gas storage, the first formation pressure of the core injection and production area is usually regarded as the formation pressure of the gas storage. The effective inventory determination method of this embodiment, when conducting pressure evaluation on the low-permeability gas storage, not only takes into account the first formation pressure of the core injection and production area that can be obtained through bottom hole testing, but also takes into account the second formation pressure of the peripheral linkage area that cannot be measured. Compared with the existing method of determining the effective inventory of the low-permeability gas storage using only the first formation pressure, the technical problem that the effective inventory of the gas storage determined by the existing method has a large deviation from the actual one can be effectively solved, and can truly reflect the injection and production seepage and inventory utilization characteristics of the low-permeability gas storage.

[0076] Further, the first controlled inventory includes: a first gas injection controlled inventory and a first gas production controlled inventory; the first formation pressure includes: a formation pressure before gas injection, a formation pressure before the first gas production, and a formation pressure after the first gas production;

[0077] In step S102, determining a first controlled inventory volume of a core injection-production area within a target injection-production period based on a first core formation pressure includes:

[0078] Calculate the first gas injection control inventory based on the formation pressure before gas injection, the formation pressure before the first gas production, and the gas injection volume within the target injection-production cycle;

[0079] The first gas production control inventory is calculated based on the formation pressure before the first gas production, the formation pressure after the first gas production, and the gas production volume within the target injection and production cycle.

[0080] Specifically, the calculation formula for the first gas injection control inventory is as follows:

[0081]

[0082] In the formula, G hzkc is the first gas injection control inventory, G Z is the gas injection volume within the target injection-production cycle, P hcq is the formation pressure before the first gas production; Z hcq The formation pressure P of the gas stored in the core injection and production area before the first gas production hcq The coefficient of deviation under hzq is the formation pressure P of the gas stored in the core injection and production area before injection hzq The coefficient of deviation below.

[0083] The calculation formula of the first gas production control inventory is as follows:

[0084]

[0085] In the formula, G hckc is the first gas production control inventory, G C is the gas production volume within the target injection-production cycle, P hch is the formation pressure after the first gas production, Z hch The formation pressure P of the gas stored in the core injection and production area after the first gas production hch The coefficient of deviation below.

[0086] It should be noted that the first formation pressure in the core injection and production area includes: the formation pressure before gas injection P hzq , the formation pressure before the first gas production P hcq And the formation pressure P after the first gas production hch All of them can be obtained through bottom hole testing; within an injection and production cycle, the gas injection volume and gas production volume are known data; the gas stored in the gas storage reservoir can specifically be natural gas, etc.

[0087] In an optional embodiment, the effective inventory determination method of the embodiment of the present invention further includes:

[0088] Obtain the gas field production data in the early stage of the reservoir construction, and determine the original formation pressure and controlled dynamic reserves of the gas storage based on the gas field production data in the early stage of the reservoir construction;

[0089] Calculate the original gas storage volume of the gas storage based on the original formation pressure and controlled dynamic reserves of the gas storage;

[0090] Based on the remaining gas volume before gas storage construction in the gas field production data in the early stage of storage construction, as well as the total gas injection volume and total gas production volume before gas production in the target injection and production period of the gas storage, the pre-gas production inventory within the target injection and production period of the gas storage is calculated.

[0091] Specifically, according to the original formation pressure and controlled dynamic reserves of the gas storage reservoir, the calculation formula for calculating the original gas storage volume of the gas storage reservoir is as follows;

[0092]

[0093] Where V is the original gas storage volume of the gas storage, P is the original formation pressure, G is the controlled dynamic reserve, T is the formation temperature of the gas storage, and P SC is the pressure of the gas stored in the gas storage under standard conditions, T SC is the temperature of the gas stored in the gas storage under standard conditions, B g is the volume coefficient of the gas stored in the gas storage reservoir, and Z is the deviation coefficient corresponding to the gas stored in the gas storage reservoir under standard conditions;

[0094] According to the remaining gas volume of the gas storage before the construction of the reservoir, combined with the total gas injection volume and total gas production volume before gas production in the target injection and production period, the calculation formula for obtaining the inventory volume of the gas storage before gas production is as follows:

[0095]

[0096] In the formula, Gk C is the inventory before gas production, i means the number of injection and production cycles, G sy is the remaining gas volume in the gas storage before the construction of the gas storage, G Zi is the gas injection volume in any injection-production cycle, G Ci It is the gas production volume in any injection-production cycle.

[0097] It should be noted that the step of calculating the original gas storage volume of the gas storage reservoir and the pre-gas production inventory within the target injection-production cycle may be before or after step S102 determines the first control inventory, as long as it is before step S103 determines the gas storage volume of the peripheral linkage area within the target injection-production cycle and the second control inventory of the peripheral linkage area. The embodiment of the present invention does not specifically limit this.

[0098] Further, in the effective inventory determination method of the embodiment of the present invention, the gas storage volume of the peripheral linkage area includes: a second gas injection gas storage volume and a second gas extraction gas storage volume;

[0099] In step S103, based on the first controlled inventory volume in the target injection-production cycle, the gas storage volume of the peripheral linkage area in the target injection-production cycle is obtained, including:

[0100] Based on the first gas injection control inventory and the first formation pressure before gas production, the first gas injection storage volume of the core injection and production area is calculated;

[0101] Based on the first gas production control inventory and the formation pressure before the first gas production, the first gas production storage volume of the core injection and production area is calculated;

[0102] The second gas injection gas storage volume is obtained according to the difference between the original gas storage volume of the gas storage reservoir and the first gas injection gas storage volume;

[0103] The second gas collection and storage volume is obtained according to the difference between the original gas storage volume of the gas storage reservoir and the first gas collection and storage volume.

[0104] Specifically, based on the first gas injection control inventory and the first formation pressure before gas production, the calculation formula for the first gas injection storage volume of the core injection and production area is as follows:

[0105]

[0106] Where V hztj is the first gas injection gas storage volume, Thcq is the formation temperature in the core injection and production area;

[0107] Based on the first gas production control inventory and the formation pressure before the first gas production, the calculation formula for the first gas production storage volume in the core injection and production area is as follows:

[0108]

[0109] Where V hctj is the first gas production and storage volume.

[0110] Further, after obtaining the first gas injection storage volume and the first gas production storage volume of the core injection and production area, the second gas injection storage volume and the second gas production storage volume of the peripheral linkage area can be calculated in combination with the original gas storage volume of the gas storage reservoir;

[0111] Specifically, the calculation formula for the second injection and production gas storage volume is as follows:

[0112] V wztj =VV hztj ;

[0113] Where V wztj is the second gas injection storage volume, V is the original gas storage volume of the gas storage, and V hztj is the first gas injection gas storage volume;

[0114] The calculation formula for the second gas production and storage volume is as follows:

[0115] V wctj =VV hctj

[0116] Where V wctj is the second gas storage volume, V is the original gas storage volume of the gas storage, V hctj is the first gas production and storage volume.

[0117] Furthermore, in the effective inventory evaluation method provided by the embodiment of the present invention, the second controlled inventory of the peripheral linkage area includes: a second gas extraction controlled inventory and a second gas injection controlled inventory;

[0118] In step 103, based on the first controlled inventory in the target injection-production cycle, the second controlled inventory in the peripheral linkage area is calculated, including:

[0119] The second gas injection control inventory is obtained according to the difference between the inventory before gas production and the first gas injection control inventory within the target injection and production cycle;

[0120] The second gas production control inventory is obtained according to the difference between the pre-gas production inventory and the first gas production control inventory within the target injection and production cycle.

[0121] Specifically, the calculation formula for the second gas injection control inventory is as follows:

[0122] G wzkc =G kc -G hzkc ;

[0123] In the formula, G wzkc Control inventory for the second gas injection, G kc is the inventory before gas extraction, G hzkc Control inventory levels for first gas injection;

[0124] The calculation formula of the second gas production control inventory is as follows:

[0125] G wckc =G kc -G hckc

[0126] In the formula, G wckc is the second gas production control inventory, G kc is the inventory before gas extraction, G hckc Control the inventory for the first gas production.

[0127] Furthermore, the second formation pressure in the peripheral linkage zone in the embodiment of the present invention includes: the second formation pressure before gas production and the second formation pressure after gas production;

[0128] Determine the second formation pressure of the peripheral linkage area within the target injection-production cycle based on the gas storage volume of the peripheral linkage area and the second controlled inventory; including:

[0129] The formation pressure before the second gas production is calculated based on the second gas injection control inventory and the second gas injection storage volume in combination with the following formula;

[0130]

[0131] Where P wcq is the second gas production formation pressure in the peripheral linkage area, T is the formation temperature of the gas storage reservoir, Z wcq The formation pressure P of the gas stored in the peripheral linkage area before the second gas production wcq The coefficient of deviation under P sc is the pressure of the gas stored in the gas storage under standard conditions, T sc V is the temperature of the gas stored in the gas storage under standard conditions. wztj is the second gas injection storage volume in the peripheral linkage area, G wzkc Control inventory for the second gas injection in the peripheral linkage area;

[0132] The formation pressure after the second gas production is calculated based on the second gas production control inventory and the second gas production storage volume in combination with the following formula;

[0133]

[0134] Where P wch is the formation pressure after the second gas production in the peripheral linkage area, V wctj is the second gas production and storage volume of the peripheral linkage area, G wckc is the second gas production control inventory in the peripheral linkage area, Z wch The formation pressure P of the gas stored in the peripheral linkage area after gas extraction wch The coefficient of deviation below.

[0135] Furthermore, the effective inventory determination method provided in the embodiment of the present invention, in step S105, determines the average formation pressure within the target injection and production period of the gas storage based on the first formation pressure, the second formation pressure, the first controlled inventory and the second controlled inventory, including:

[0136] According to the first formation pressure before gas production and the second formation pressure before gas production, as well as the first gas injection control inventory and the second gas injection control inventory, and in combination with the following formula, the average formation pressure before gas production in the gas storage reservoir within the target injection and production period is calculated;

[0137]

[0138] Where P cq is the average formation pressure before gas production in the gas storage, G hzkc is the first gas injection control inventory, P hcq is the formation pressure before the first gas production, G hzkc Control inventory level for first gas injection.

[0139] According to the first gas production formation pressure and the second gas production formation pressure, as well as the first gas production control inventory and the second gas production control inventory, and in combination with the following formula, the average formation pressure after gas production in the gas storage reservoir within the target injection and production period is calculated;

[0140]

[0141] Where P ch is the average formation pressure after gas production in the gas storage, G c is the gas production volume within the target injection-production cycle, P wch is the formation pressure after the first gas production, G hckc Control the inventory for the first gas production.

[0142] The effective inventory determination method provided in an embodiment of the present invention weights the formation pressure with the inventory when using the first formation pressure and the second formation pressure to determine the average formation pressure within the target injection and production cycle of the gas storage reservoir. Since the inventory reflects the gas-containing space underground, the calculation result obtained by calculating the average pressure of the gas storage reservoir weighted by the inventory is more in line with the formation conditions.

[0143] Furthermore, in the method for determining effective inventory provided by the embodiment of the present invention, in step S106, based on the average formation pressure and in combination with the obtained gas production volume in the target injection and production cycle, the effective inventory volume of the gas storage before gas production in the target injection and production cycle is determined. The specific calculation formula is as follows:

[0144]

[0145] In the formula, G yxkr is the effective storage volume of the gas storage before gas extraction, Z cq is the deviation coefficient of the gas stored in the gas storage under the average formation pressure before gas extraction, Z ch It is the deviation coefficient of the gas stored in the gas storage under the average formation pressure after gas extraction.

[0146] Furthermore, the method for determining the effective inventory of a low-permeability gas reservoir type gas storage provided in an embodiment of the present invention may also include:

[0147] According to the effective storage before gas extraction

[0148] Inventory and pre-gas production inventory to determine the gas storage inventory utilization rate;

[0149] Specifically, the specific calculation formula for determining the gas storage inventory utilization rate is as follows:

[0150]

[0151] Where η is the utilization rate of gas storage inventory.

[0152] It should be noted that the deviation coefficients corresponding to the gas at different formation pressures in the embodiments of the present invention, and the corresponding relationship between different formation pressures and the deviation coefficients, can be obtained through relevant international standards.

[0153] The following takes a gas reservoir type gas storage as an example to exemplarily illustrate the effective inventory determination method provided by an embodiment of the present invention. The gas stored in the gas storage in this embodiment is natural gas. After the gas storage is divided into a core injection and production area and a peripheral linkage area according to the injection and production operation characteristics of the low permeability gas storage, determining the effective inventory may specifically include the following steps:

[0154] Step 1: Based on the gas field production data of a gas storage facility before its construction, the original formation pressure P of the gas reservoir is evaluated to be 30.4 MPa, the formation temperature T is 380.5 K, and the pressure of natural gas under standard conditions P is SC is 0.101MPa, and the temperature of natural gas under standard conditions is T SC is 293K; the corresponding deviation coefficient Z of natural gas under standard conditions is 0.9864, the dynamic reserves G is 1.04 billion cubic meters, and the original gas storage volume V of the gas reservoir is calculated to be 4.426 million cubic meters;

[0155]

[0156] Step 2: According to the remaining gas volume G before building the library sy 235 million cubic meters, combined with the total gas injection volume before gas production during the target injection and production cycle The total gas production is 2.17 billion cubic meters The inventory volume G of a gas storage after the seventh gas injection and before the seventh gas extraction can be obtained. kc It is 910 million cubic meters.

[0157]

[0158] Step 3: According to the target injection and production cycle of the gas reservoir, the gas injection volume G Z 311 million cubic meters, gas production G C The formation pressure before gas injection is 313 million cubic meters. hzq is 15.9MPa, corresponding to the natural gas deviation coefficient Z under pressure conditions hzq is 0.9224; the formation pressure before the first gas production is P hcq is 32.0MPa, corresponding to the natural gas deviation coefficient Z under pressure conditions hcq is 1.0162; the formation pressure after the first gas production is P hch The natural gas deviation coefficient Z under the corresponding pressure condition is 15.0MPa. hch The first gas injection control inventory G in the core injection and production area is evaluated. hzkc The first gas production control inventory in the core injection and production area is G hckc 623 million cubic meters;

[0159]

[0160]

[0161] Step 4: The first gas injection control reservoir capacity G of the core injection and production area determined in step 3 zhkc The first gas production control storage capacity is 658 million cubic meters. chkcThe formation pressure before the first gas production is P hcq is 33.2MPa, the first gas injection storage volume V in the core injection-production area can be obtained hztj The second gas production and storage volume is 2.642 million cubic meters. hctj 2.501 million square meters;

[0162]

[0163]

[0164] Step 5: The original gas storage volume V calculated in step 1 is 4.426 million cubic meters, and the first gas injection control gas storage volume V of the core injection and production area calculated in step 4 is hztj The first gas production control gas storage volume V of the core injection and production area is 2.642 million cubic meters hztj The second gas injection control gas storage volume V in the peripheral linkage area can be calculated. wztj The second gas production control gas storage volume V is 1.784 million cubic meters and the peripheral linkage area wctj It is 1.925 million square meters.

[0165] V wztj =VV hztj =442.6-264.2=178.4

[0166] V wctj =VV hctj =442.6-250.1=192.5

[0167] Step 6: Based on the gas inventory G calculated in step 2 kc It is 910 million cubic meters. The first gas injection control inventory of the core injection and production area calculated in step 3 is 658 million cubic meters; the first gas production control inventory of the core injection and production area is 623 million cubic meters; the second gas injection control inventory of the peripheral linkage area can be calculated to be 252 million cubic meters, and the second gas production control inventory of the peripheral linkage area is 287 million cubic meters.

[0168] G wzkc =G kc -G hzkc =9.1-6.58=2.52

[0169] G wckc =G kc -G hckc =9.1-6.23=2.87

[0170] Step 7: Based on the second gas injection control inventory of 252 million cubic meters and the second gas injection gas storage volume of 1.784 million cubic meters in the peripheral linkage area calculated in steps 5 and 6, calculate the formation pressure P after the second gas injection in the peripheral linkage area. wcq =17.13MPa; and, based on the second gas production inventory of 287 million cubic meters and the second gas production storage volume of 1.925 million cubic meters in the peripheral linkage area, calculate the second gas production formation pressure P in the peripheral linkage area wch =18.1MPa;

[0171]

[0172]

[0173] Step 8: According to the first formation pressure P before gas production in step 2 hcq 33.2MPa, formation pressure after first gas production P hch 15.9MPa; Calculate the formation pressure P before the second gas production according to steps 6 and 7 wcq The formation pressure after the second gas production is 17.13MPa. wch is 18.1MPa; according to the weight of the inventory, the average formation pressure P before gas extraction in the gas storage can be obtained: cq =28.75MPa, average formation pressure after gas production P ch =16.96MPa;

[0174]

[0175]

[0176] Step 9: According to step 8, the average formation pressure before and after gas production in the gas storage is calculated to be 28.75MPa and 16.96MPa; combined with the periodic gas production G c It is 313 million cubic meters, and the effective storage volume of the gas storage facility can be calculated as G yxkr =835.3 million cubic meters, and the evaluated gas storage inventory utilization rate η = 91.79%.

[0177]

[0178]

[0179] The method for determining the effective inventory of a low-permeability gas reservoir type gas storage provided by the embodiment of the present invention is aimed at the problem that the formation pressure of a low-permeability gas reservoir type gas storage cannot reach equilibrium in a short period of time after injection and production, and the formation pressure and effective inventory of the gas storage are difficult to evaluate. First, the total gas storage pore volume (i.e., the original gas storage volume) of the gas storage can be calculated based on the gas field development data; secondly, according to the injection and production operation characteristics of the low-permeability gas storage reservoir, the gas storage area is divided into a core injection and production area and a peripheral linkage area, and the effective inventory, formation pressure and other parameters are calculated and controlled respectively. The average formation pressure before and after gas production in the gas storage reservoir is determined by weighting the formation pressure with the controlled inventory; finally, the effective inventory of the gas reservoir and other parameters are determined in combination with the gas production within the target injection and production cycle. The technical solution of this method effectively solves the technical problem that the effective inventory of the gas reservoir determined by only testing the formation pressure has a large deviation from the actual situation, and truly reflects the injection and production seepage and inventory utilization characteristics of the low-permeability gas storage reservoir, thereby accurately solving the problem of how to evaluate the inventory of a low-permeability gas reservoir type gas storage reservoir.

[0180] Based on the same inventive concept, Figure 2 As shown, the embodiment of the present invention also provides a device for determining the effective inventory of a low-permeability gas reservoir type gas storage, comprising:

[0181] Area division module 11: used to divide the low permeability gas storage into a core injection and production area and a peripheral linkage area according to the injection and production operation characteristics of the low permeability gas storage; the core injection and production area refers to the area that can be affected by pressure conduction when the formation pressure recovers to a stable pressure within the well closing balance time during the well closing balance stage of the injection and production wells of the low permeability gas storage; the peripheral linkage area refers to the area outside the core injection and production area when the formation pressure recovers to a stable pressure within the well closing balance time during the injection and production wells of the low permeability gas storage;

[0182] The first determination module 12 is used to obtain a first formation pressure of a core injection-production area within a target injection-production period, and determine a first controlled inventory volume of the core injection-production area within the target injection-production period based on the first formation pressure;

[0183] The second determination module 13 is used to obtain the gas storage volume of the peripheral linkage area within the target injection-production cycle and the second controlled inventory volume of the peripheral linkage area within the target injection-production cycle based on the first controlled inventory volume within the target injection-production cycle;

[0184] The third determination module 14 is used to determine the second formation pressure of the peripheral linkage zone within the target injection-production cycle based on the gas storage volume of the peripheral linkage zone and the second controlled inventory;

[0185] A fourth determination module 15 is used to determine an average formation pressure within a target injection-production cycle of the gas storage based on the first formation pressure, the second formation pressure, the first controlled inventory amount, and the second controlled inventory amount;

[0186] The fifth determination module 16 is used to determine the effective inventory of the gas storage within the target injection and production cycle based on the average formation pressure and the obtained gas production within the target injection and production cycle.

[0187] Based on the same inventive concept, an embodiment of the present invention also provides an effective inventory determination and analysis system for a low-permeability gas reservoir type gas storage facility, comprising a memory and a processor, wherein a computer program is stored on the memory, and when the computer program is executed by the processor, the effective inventory determination method for a low-permeability gas reservoir type gas storage facility as described above is implemented.

[0188] Based on the same inventive concept, an embodiment of the present invention further provides a storage medium having a computer program stored thereon. When the computer program is executed by a processor, the above-mentioned method for determining the effective inventory of a low-permeability gas reservoir type gas storage is implemented.

[0189] Unless otherwise specifically stated, terms such as processing, computing, calculating, determining, displaying, etc. may refer to the actions and / or processes of one or more processing or computing systems, or similar devices, which operate and convert data represented as physical (e.g., electronic) quantities within registers or memories of a processing system into other data similarly represented as physical quantities within memories, registers, or other such information storage, transmission, or display devices of the processing system. Information and signals may be represented using any of a variety of different techniques and methods. For example, data, instructions, commands, information, signals, bits, symbols, and chips mentioned throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, light fields or particles, or any combination thereof.

[0190] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of the present invention. The attached method claims present the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0191] In the above detailed description, various features are grouped together in a single embodiment to simplify the invention. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than those clearly stated in each claim. On the contrary, as reflected in the attached claims, the invention is in a state of having less than all the features of the disclosed individual embodiments. Therefore, the attached claims are hereby expressly incorporated into the detailed description, with each claim standing alone as a separate preferred embodiment of the invention.

[0192] Those skilled in the art will also appreciate that the various illustrative logic blocks, modules, circuits, and algorithmic steps described in conjunction with the embodiments herein may all be implemented as electronic hardware, computer software, or a combination thereof. In order to clearly illustrate the interchangeability between hardware and software, various illustrative components, blocks, modules, circuits, and steps are generally described above around their functions. Whether such functions are implemented as hardware or software depends on the specific application and the design constraints imposed on the entire system. A skilled person may implement the described functions in an alternative manner for each specific application, but such implementation decisions should not be interpreted as departing from the scope of protection of the present invention.

[0193] The steps of the method or algorithm described in conjunction with the embodiments herein may be directly embodied as hardware, a software module executed by a processor, or a combination thereof. The software module may be located in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a mobile disk, a CD-ROM, or any other form of storage medium well known in the art. An exemplary storage medium is connected to the processor so that the processor can read information from the storage medium and can write information to the storage medium. Of course, the storage medium may also be an integral part of the processor. The processor and the storage medium may be located in an ASIC. The ASIC may be located in a user terminal. Of course, the processor and the storage medium may also be present in a user terminal as discrete components.

[0194] For software implementation, the techniques described in this application can be implemented with modules (e.g., procedures, functions, etc.) that perform the functions described in this application. These software codes can be stored in a memory unit and executed by a processor. The memory unit can be implemented within the processor or outside the processor. In the latter case, it is coupled to the processor in a communication manner via various means, which are well known in the art.

[0195] The above description includes examples of one or more embodiments. Of course, it is impossible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it should be recognized by those skilled in the art that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is covered in a manner similar to the term "including", just as "including," is explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to mean "non-exclusive or".

Claims

1. A method for determining the effective inventory of a low-permeability gas reservoir, characterized in that: include: According to the injection and production operation characteristics of the low-permeability gas storage reservoir, the gas storage reservoir is divided into a core injection and production area and a peripheral linkage area; the core injection and production area refers to the area that can be affected by pressure conduction when the formation pressure recovers to a stable pressure within the well-closing balance time during the shut-in balance stage of the injection and production wells of the low-permeability gas storage reservoir; the peripheral linkage area refers to the area outside the core injection and production area when the formation pressure recovers to a stable pressure within the well-closing balance time during the injection and production wells of the low-permeability gas storage reservoir; Acquiring a first formation pressure of a core injection-production area within a target injection-production cycle, and determining a first controlled inventory volume of the core injection-production area within the target injection-production cycle based on the first formation pressure; Based on the first controlled inventory volume in the target injection-production cycle, the gas storage volume of the peripheral linkage area and the second controlled inventory volume of the peripheral linkage area in the target injection-production cycle are obtained; Determining a second formation pressure of the peripheral linkage zone within a target injection-production cycle based on the gas storage volume of the peripheral linkage zone and the second controlled inventory; Determining an average formation pressure within a target injection-production cycle of the gas storage based on the first formation pressure, the second formation pressure, the first controlled inventory amount, and the second controlled inventory amount; Based on the average formation pressure and in combination with the obtained gas production within the target injection-production cycle, the effective inventory volume of the gas storage before gas production within the target injection-production cycle is determined.

2. The method for determining the effective inventory of a low permeability gas reservoir type gas storage facility according to claim 1, characterized in that: The first controlled inventory includes: a first gas injection controlled inventory and a first gas production controlled inventory; the first formation pressure includes: a formation pressure before gas injection, a formation pressure before the first gas production, and a formation pressure after the first gas production; Determining a first controlled inventory volume in a core injection-production area within a target injection-production period based on the first formation pressure includes: Calculating the first gas injection control inventory based on the formation pressure before gas injection, the formation pressure before the first gas production, and the gas injection volume within the target injection-production cycle; The first gas production control inventory is calculated based on the formation pressure before the first gas production, the formation pressure after the first gas production, and the gas production volume within the target injection and production cycle.

3. The method for determining the effective inventory of a low permeability gas reservoir type gas storage according to claim 2, characterized in that: Also includes: Obtain the gas field production data in the early stage of the reservoir construction, and determine the original formation pressure and controlled dynamic reserves of the gas storage based on the gas field production data in the early stage of the reservoir construction; Calculate the original gas storage volume of the gas storage based on the original formation pressure and controlled dynamic reserves of the gas storage; Based on the remaining gas volume before gas storage construction in the gas field production data in the early stage of storage construction, as well as the total gas injection volume and total gas production volume before gas production in the target injection and production period of the gas storage, the pre-gas production inventory within the target injection and production period of the gas storage is calculated.

4. The method for determining the effective inventory of a low permeability gas reservoir type gas storage according to claim 3, characterized in that: The gas storage volume of the peripheral linkage area includes: a second gas injection gas storage volume and a second gas extraction gas storage volume; Based on the first controlled inventory within the target injection-production cycle, the gas storage volume of the peripheral linkage area within the target injection-production cycle is obtained, including: Based on the first gas injection control inventory and the first formation pressure before gas production, a first gas injection storage volume of the core injection and production area is calculated; Based on the first gas production control inventory and the first formation pressure before gas production, a first gas production storage volume of the core injection and production area is calculated; Obtaining the second gas injection gas storage volume according to the difference between the original gas storage volume of the gas storage reservoir and the first gas injection gas storage volume; The second gas collection and storage volume is obtained according to the difference between the original gas storage volume of the gas storage reservoir and the first gas collection and storage volume.

5. The method for determining the effective inventory of a low permeability gas reservoir type gas storage according to claim 4, characterized in that: The second controlled inventory of the peripheral linkage area includes: a second gas extraction controlled inventory and a second gas injection controlled inventory; Based on the first controlled inventory quantity within the target injection-production cycle, the second controlled inventory quantity of the peripheral linkage area is calculated, including: Obtaining the second gas injection control inventory amount according to the difference between the pre-gas production inventory amount and the first gas injection control inventory amount within the target injection and production cycle; The second gas production control inventory is obtained according to the difference between the pre-gas production inventory and the first gas production control inventory within the target injection and production cycle.

6. The method for determining the effective inventory of a low permeability gas reservoir type gas storage according to claim 5, characterized in that: The second formation pressure includes: a second formation pressure before gas production and a second formation pressure after gas production; Determining the second formation pressure of the peripheral linkage area within the target injection-production cycle based on the gas storage volume of the peripheral linkage area and the second controlled inventory volume; comprising: The second formation pressure before gas production is calculated based on the second gas injection control inventory and the second gas injection storage volume in combination with the following formula; Where P wcq is the second gas production formation pressure in the peripheral linkage area, T is the formation temperature of the gas storage reservoir, Z wcq The formation pressure P of the gas stored in the peripheral linkage area before the second gas production wcq The coefficient of deviation under P sc is the pressure of the gas stored in the gas storage under standard conditions, T sc is the temperature of the gas stored in the gas storage under standard conditions, V wztj is the second gas injection storage volume in the peripheral linkage area, G wzkc Control inventory for the second gas injection in the peripheral linkage area; The second gas production controlled inventory and the second gas production storage volume are used to calculate the second gas production formation pressure in combination with the following formula; Where P wch is the formation pressure after the second gas production in the peripheral linkage area, V wctj is the second gas production and storage volume of the peripheral linkage area, G wckc is the second gas production control inventory in the peripheral linkage area, Z wch The formation pressure P of the gas stored in the peripheral linkage area after gas extraction wch The coefficient of deviation below.

7. The method for determining the effective inventory of a low permeability gas reservoir type gas storage according to claim 6, characterized in that: Determining an average formation pressure within a target injection-production cycle of a gas storage reservoir based on the first formation pressure, the second formation pressure, the first controlled inventory amount, and the second controlled inventory amount includes: According to the first formation pressure before gas production and the second formation pressure before gas production, as well as the first gas injection control inventory and the second gas injection control inventory, and in combination with the following formula, the average formation pressure before gas production of the gas storage reservoir within the target injection and production period is calculated; Where P cq is the average formation pressure before gas production in the gas storage, P hcq is the formation pressure before the first gas production, G hzkc Control inventory levels for first gas injection; According to the first gas production formation pressure and the second gas production formation pressure, as well as the first gas production control inventory and the second gas production control inventory, and in combination with the following formula, the average gas production formation pressure of the gas storage reservoir within the target injection and production period is calculated; Where P ch is the average formation pressure after gas production in the gas storage, G c is the gas production volume in the target injection-production cycle, Pwch is the formation pressure after the first gas production, G hckc Control the inventory for the first gas production.

8. The method for determining the effective inventory of a low permeability gas reservoir type gas storage according to claim 7, characterized in that: Also includes: The utilization rate of the gas storage reservoir inventory is determined based on the effective inventory volume of the gas storage reservoir before gas extraction and the inventory volume before gas extraction.

9. A device for determining effective inventory of a low-permeability gas reservoir, characterized in that: include: Area division module: used to divide the low permeability gas storage into a core injection and production area and a peripheral linkage area according to the injection and production operation characteristics of the low permeability gas storage; the core injection and production area refers to the area that can be affected by pressure conduction when the formation pressure recovers to a stable pressure during the shut-in balance period of the injection and production wells of the low permeability gas storage; the peripheral linkage area refers to the area outside the core injection and production area when the formation pressure recovers to a stable pressure during the shut-in balance period of the injection and production wells of the low permeability gas storage; A first determination module: used to obtain a first formation pressure of a core injection-production area within a target injection-production period, and determine a first controlled inventory volume of the core injection-production area within the target injection-production period based on the first formation pressure; A second determination module is used to obtain the gas storage volume of the peripheral linkage area within the target injection-production cycle and the second controlled inventory of the peripheral linkage area based on the first controlled inventory within the target injection-production cycle; A third determination module is used to determine a second formation pressure of the peripheral linkage zone within a target injection-production cycle based on the gas storage volume of the peripheral linkage zone and the second controlled inventory; a fourth determination module, configured to determine an average formation pressure within a target injection-production cycle of the gas storage reservoir based on the first formation pressure, the second formation pressure, the first controlled inventory amount, and the second controlled inventory amount; The fifth determination module is used to determine the effective inventory of the gas storage reservoir within the target injection and production cycle based on the average formation pressure and the obtained gas production within the target injection and production cycle.

10. A system for determining and analyzing the effective inventory of a low-permeability gas reservoir, characterized in that: The method comprises a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the method for determining the effective inventory of a low-permeability gas reservoir type gas storage facility as described in any one of claims 1 to 8 is implemented.

11. A storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for determining the effective inventory of a low-permeability gas reservoir type gas storage facility according to any one of claims 1 to 8 is implemented.

Images