Method and device for diagnosing residual potential after insufficient liquid supply of gas lift well

Abstract

The invention discloses a method and device for diagnosing residual potential after insufficient liquid supply of a gas lift well, and the method comprises the steps: determining the elastic yield of an oil reservoir according to the cumulative production of a single well and the formation pressure; the deepening gas lift punching depth is determined according to the shaft integrity and an oil production engineering method; according to the elastic yield and the deepening gas lift punching depth, calculating the predicted oil increasing amount of the deepening gas lift; and on the basis of deepening the gas lift predicted oil increasing amount, the residual potential after insufficient liquid supply of the gas lift well is diagnosed. The method provided by the invention not only solves the problem of shaft integrity possibly caused by deepening the gas lift, but also realizes maximization of the deepening gas lift yield increasing effect; the problem that the punching depth is too small, and the yield increasing effect is small is solved, and the technical failure problem caused by short circuit of gas lift gas from the lowermost-stage gas lift valve due to the fact that the punching depth is too small is also solved.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas reservoir engineering in oil and gas field development, and particularly to a method and device for diagnosing the remaining potential after insufficient liquid supply in a gas lift well. Background Art

[0002] After the self-flowing period of carbonate oil wells ends, in order to further release the elastic energy of the formation and increase the cumulative production per well, generally, it will be switched to a pumping unit or gas lift production. For carbonate oil wells with gas lift strings already installed, during the later stage of gas lift, there is a problem of insufficient liquid supply. After the liquid level in the tubing drops to the lowest-stage gas lift valve, there is a problem that the well cannot produce continuously due to being lifted empty. The traditional method is to increase the liquid level in the tubing by water injection to displace oil or replace the string to increase the depth of the gas lift valve below, so as to maintain the continuous production of the gas lift well and increase the cumulative production per well. However, due to the complexity of the internal structure of carbonate reservoirs, it is difficult to replace oil with water during water injection to displace oil, and there is a problem of slow recovery of the liquid level in the tubing; while replacing the string has a high operation cost. Summary of the Invention

[0003] The purpose of the present invention is to provide a method and device for diagnosing the remaining potential after insufficient liquid supply in a gas lift well. The purpose of the present invention is to solve the problems of slow liquid level recovery by relying on water injection to displace oil and high operation cost of replacing the string after insufficient liquid supply in carbonate gas lift wells. By quantitatively calculating and diagnosing the remaining potential after insufficient liquid supply in a gas lift well, finally, a report on diagnosing the remaining potential size after insufficient liquid supply in carbonate gas lift wells is formed. To achieve the above purpose, the present invention provides the following technical solutions:

[0004] The present invention provides a method for diagnosing the remaining potential after insufficient liquid supply in a gas lift well, and the method includes,

[0005] Determining the elastic productivity of the oil reservoir according to the cumulative production per well and the formation pressure;

[0006] Determining the deepening gas lift perforation depth according to the wellbore integrity and oil production engineering methods;

[0007] Calculating the expected increased oil production of deepening gas lift according to the elastic productivity and the deepening gas lift perforation depth;

[0008] Diagnosing the remaining potential after insufficient liquid supply in the gas lift well based on the expected increased oil production of deepening gas lift.

[0009] Optionally, before determining the elastic productivity of the oil reservoir, the method further includes:

[0010] Determining whether the gas lift well has insufficient liquid supply according to the comparison between the surface opening pressure of the lowest-stage gas lift valve in the gas lift well and the casing pressure and the test results of the flow temperature and flow pressure gradient; wherein,

[0011] When the surface opening pressure of the bottom - most gas - lift valve is less than or equal to the predetermined pressure value, and through the flowing temperature - flowing pressure gradient test, it is determined that the tubing above the depth of the bottom - most gas - lift valve is in the gas phase and the tubing below is in the oil phase, it is determined that the liquid supply of the gas - lift well is insufficient.

[0012] Optionally, the calculation of the reservoir elastic production rate based on the cumulative production of a single well and the formation pressure is as follows:

[0013] ε=N p B o / ρ o / △P

[0014] Where ε represents the reservoir elastic production rate, N p represents the cumulative oil production, B o represents the formation oil volume factor, ρ o represents the surface crude oil density, and △P represents the formation pressure drop value.

[0015] Optionally, the determination of the deepening gas - lift perforation depth according to the wellbore integrity and the oil production engineering method includes:

[0016] Calculate the external collapse pressure of the casing when the casing pressure is 0 according to the formation pressure and the external collapse strength of the casing corresponding to different well depths, and obtain the perforation depth H to ensure the wellbore integrity 1 ;

[0017] Using the oil production engineering method, calculate the distribution line L of the annular injection gas flowing pressure along the well depth when the casing pressure is equal to the surface opening pressure corresponding to the bottom - most gas - lift valve 1 , and calculate the distribution line L of the flowing pressure in the tubing along the well depth using the wellhead oil pressure and the density of the oil - gas mixture during normal gas - lift production in the tubing 2 , L 1 and L 2 The well depth corresponding to the intersection point of the lines is the perforation depth H to ensure that the gas - lift gas will not "short - circuit" through the bottom - most gas - lift valve 2 ;

[0018] According to the perforation depth H to ensure the wellbore integrity 1 and the perforation depth H to ensure that the gas - lift gas will not "short - circuit" through the bottom - most gas - lift valve 2 , H 1 and H 2 The minimum value of the two is the deepening gas - lift perforation depth H js .

[0019] Optionally, the calculation method of the flowing pressure in the tubing along the well depth is as follows:

[0020] P yg (H)=P c +0.000001*ρ hh *g*H

[0021] Among them, P hk represents the flowing pressure inside the tubing; P c represents the wellhead oil pressure; ρ hh represents the density of the oil-gas mixture inside the tubing during normal gas lift production; g represents the acceleration due to gravity; H represents the depth;

[0022] The calculation method of the annular gas injection flow gradient along the well depth is as follows:

[0023] P hk (H) = P t + P g (H) - f g (H)

[0024] Among them, P hk represents the annular gas injection flowing pressure; P t represents the wellhead casing pressure, and its value is equal to the ground opening pressure value of the lowest-stage gas lift valve; P g represents the static gas column pressure; f g represents the annular gas injection friction; H represents the depth;

[0025] The deepened gas lift perforation depth H js , the calculation method is as follows:

[0026] H js = min{H 1 , H 2}.

[0027] Optionally, the calculation formula for determining the expected increased oil production of the deepened gas lift based on the reservoir elastic productivity and the deepened gas lift perforation depth is as follows:

[0028] N = ε * ρ o * [P 1 - (P t1 + ▽P 1 * H js / 100 + ▽P 2 * (H 中 - H js ) / 100)] / B o1

[0029] Among them, N represents the expected increased oil production of the deepened gas lift; ε represents the underground elastic productivity; ρ o represents the ground crude oil density; P 1 represents the formation pressure corresponding to when the lowest-stage gas lift valve is emptied; P t1 represents the wellhead oil pressure corresponding to when the deepened gas lift is emptied; ▽P 1 represents the pressure gradient above the perforation point after the perforation point of the deepened gas lift is emptied; H js represents the deepened gas lift perforation depth; ▽P 2Indicates the pressure gradient below the perforation point after the perforation point for deepened gas lift is emptied; H 中 Indicates the depth in the reservoir; B o1 Indicates the formation oil volume factor at the formation pressure corresponding to the perforation point after the perforation point for deepened gas lift is emptied.

[0030] Optionally, the diagnosing the remaining potential after the gas lift well has insufficient liquid supply based on the expected increased oil production by deepened gas lift includes

[0031] Calculating the output-input ratio after the gas lift well has insufficient liquid supply based on the expected increased oil production by deepened gas lift;

[0032] Diagnosing the remaining potential after the gas lift well has insufficient liquid supply based on the water cut, elastic production rate, expected increased oil production, and output-input ratio of the gas lift well before the insufficient liquid supply.

[0033] Optionally, the output-input ratio is calculated as follows:

[0034] R = x * N * (1 - t) / [y 1 * N + y 2 * N + z]

[0035] wherein, R represents the output-input ratio; x represents the crude oil sales price; N represents the expected increased oil production by deepened gas lift; t represents the tax rate; y 1 represents the operating cost per ton of oil; y 2 represents the gas lift cost per ton of oil and gas; z represents the cost of the deepened gas lift measure.

[0036] The present invention also provides a device for diagnosing the remaining potential after the gas lift well has insufficient liquid supply. The device includes,

[0037] A first determination module, configured to determine the elastic production rate of the reservoir according to the cumulative production of a single well and the formation pressure;

[0038] A second determination module, configured to determine the perforation depth for deepened gas lift according to the wellbore integrity and the oil production engineering method;

[0039] A calculation module, configured to calculate the expected increased oil production by deepened gas lift according to the elastic production rate and the perforation depth for deepened gas lift;

[0040] A diagnosis module, configured to diagnose the remaining potential after the gas lift well has insufficient liquid supply based on the expected increased oil production by deepened gas lift.

[0041] Optionally, the device further includes a determination module, and the steps executed by the determination module include:

[0042] Determining whether the gas lift well has insufficient liquid supply according to the comparison between the surface opening pressure of the bottommost gas lift valve of the gas lift well and the casing pressure and the test results of the flowing temperature and flowing pressure gradient; wherein,

[0043] When the surface opening pressure of the bottom - most gas lift valve is less than or equal to a predetermined pressure value, and through the flowing temperature - flowing pressure gradient test, it is determined that the tubing above the depth of the bottom - most gas lift valve is in the gas phase and the tubing below is in the oil phase, it is determined that the liquid supply of the gas lift well is insufficient.

[0044] A storage medium, characterized in that a program or instructions are stored on the storage medium, and when the program or instructions are run by a processor, the steps of a method for diagnosing the remaining potential after insufficient liquid supply in a gas lift well as described above are implemented.

[0045] An electronic device, including a memory, a processor, and a computer program stored on the memory and operable on the processor, characterized in that when the processor executes the program, the steps of a method for diagnosing the remaining potential after insufficient liquid supply in a gas lift well as described above are implemented.

[0046] The technical effects and advantages of the present invention:

[0047] The diagnosis method of the present invention has accurate judgment and strong operability. After diagnosis, for carbonate gas lift wells with large potential, the success rate of deepening gas lift after insufficient liquid supply is high. 12 wells with a comprehensive score of more than 20 points have all achieved success through deepening gas lift, and the success rate is 100%. After insufficient liquid supply in carbonate gas lift wells, by perforating the tubing at a reasonable depth below the gas lift valve to deepen gas lift, the problem of slow liquid level recovery by water injection to displace oil is avoided, and the problem of high operation cost for replacing the tubing string is solved. Only one tubing - through perforation is required, with low operation cost, high success rate, obvious production - increasing effect, and a high output - input ratio. The method proposed by the present invention not only solves the possible wellbore integrity problems caused by deepening gas lift, but also maximizes the production - increasing effect of deepening gas lift; it not only avoids the problem of small production - increasing effect due to too shallow perforation depth, but also avoids the problem of technical failure caused by "short - circuit" of the gas lift gas from the bottom - most gas lift valve when the perforation depth is too large.

[0048] Other features and advantages of the present invention will be described in the subsequent specification, and, in part, will become obvious from the specification, or will be understood by implementing the present invention. The objectives and other advantages of the present invention can be realized and obtained through the structures pointed out in the specification and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a flow chart of the method for diagnosing the remaining potential after insufficient liquid supply in a gas lift well of the present invention;

[0050] Figure 2 It is a schematic diagram of deepening gas lift after insufficient liquid supply in a carbonate gas lift well of the present invention;

[0051] Figure 3 It is an intersection diagram of the flowing gradient in the tubing above the perforation point and the annular injection gas flowing gradient of the present invention;

[0052] Figure 4 Schematic structural diagram of an electronic device provided by an embodiment of the present invention. Specific embodiments

[0053] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0054] To solve the deficiencies of the prior art, the present invention discloses a method for diagnosing the remaining potential after insufficient liquid supply in a gas lift well, as Figure 1 shown, the method includes

[0055] Step 1: Determine that the liquid supply of the gas lift well is insufficient.

[0056] Step 2: Determine the elastic production rate of the oil reservoir according to the cumulative production of a single well and the formation pressure.

[0057] Step 3: Determine the deepening gas lift perforation depth according to the wellbore integrity and oil production engineering methods.

[0058] Step 4: Calculate the expected increased oil production of the deepening gas lift according to the elastic production rate and the deepening gas lift perforation depth.

[0059] Step 5: Based on the expected increased oil production of the deepening gas lift, diagnose the remaining potential after insufficient liquid supply in the gas lift well.

[0060] Figure 2 Schematic diagram of deepening gas lift after insufficient liquid supply in a carbonate rock gas lift well involved in the method of the present invention, as Figure 2 shown, in the gas lift well, the tubing inside the casing extends deep into the oil reservoir. The crude oil in the oil reservoir flows upward along the tubing. Multiple gas lift valves or deepening gas lift perforation points are arranged on the tubing. The gas lift gas flows downward in the annular space formed by the tubing and the casing, enters the tubing through the gas lift valve or deepening gas lift perforation point. After the gas lift gas is mixed with the crude oil in the tubing, an oil-gas mixture is formed, and the oil-gas mixture continues to flow upward along the tubing to the ground. The well depth is H, and the lowermost stage gas lift valve is at the end far from the wellhead. The tubing perforation is arranged below the lowermost stage gas lift valve. Among them, the depth from the wellhead to the tubing perforation is the deepening gas lift perforation depth H js .

[0061] In a specific embodiment of the present invention, determining that the liquid supply of the gas lift well is insufficient includes diagnosing whether the liquid supply is insufficient according to the comparison between the surface opening pressure of the lowermost stage gas lift valve of the carbonate rock gas lift well and the casing pressure and the results of the flow ladder test. Specifically:

[0062] First, preliminarily judge whether the liquid supply is insufficient by comparing the surface opening pressure of the bottom - most gas lift valve in the carbonate gas lift well with the current casing pressure, and then further determine whether the liquid supply is insufficient in combination with the results of the flow - gradient test. When the surface opening pressure of the bottom - most gas lift valve is less than or equal to the predetermined pressure value, and through the flow - temperature - pressure gradient test, it is determined that the tubing above the bottom - most gas lift valve is in the gas phase and the tubing below is in the oil phase, it is determined that the liquid supply of the gas lift well is insufficient.

[0063] Taking Well A as an example, in October 2022, the casing pressure of Well A had dropped to 7.80 MPa, approaching the surface opening pressure of the bottom - most gas lift valve, which was 7.77 MPa. It was preliminarily judged that the bottom - most gas lift valve had been emptied and the liquid supply was insufficient. In November 2022, a flow - temperature - pressure gradient test was carried out. The results showed that the tubing above the depth of the bottom - most gas lift valve was in the gas phase and the tubing below was in the oil phase. Thus, it was confirmed that the area below the depth h of the bottom - most gas lift valve had indeed been emptied and the liquid supply of the gas lift well was insufficient.

[0064] In a specific embodiment of the present invention, the calculation of the reservoir elastic productivity determined according to the cumulative production of a single well and the formation pressure is as follows:

[0065] ε = N p B o / ρ o / △P;

[0066] Among them, ε represents the reservoir elastic productivity, m 3 / MPa; N p represents the cumulative oil production, t; B o represents the formation oil volume factor, dimensionless; ρ o represents the surface crude oil density, g / cm 3 ; △P represents the formation pressure drop value, MPa.

[0067] Taking Well A as an example, as of November 2022, the cumulative oil production N of Well A p was 1.14×10 4 t, the formation oil volume factor B o was 1.3352 m 3 / m 3 , the surface crude oil density ρ o was 0.8687 g / cm 3 , and during this period, the formation pressure drop value △P was 13.1 MPa. The calculated reservoir elastic productivity ε of Well A was 1337 m 3 / MPa.

[0068] In a specific embodiment of the present invention, step 3: Determine the deepening gas lift perforation depth according to wellbore integrity and oil production engineering methods, specifically:

[0069] Determining the deepening gas lift perforation depth according to wellbore integrity and production engineering methods includes:

[0070] Calculating the external collapse pressure of the casing when the casing pressure is 0 based on the formation pressure and casing external collapse strength corresponding to different well depths, and obtaining the perforation depth H to ensure wellbore integrity 1 ;

[0071] Using production engineering methods, calculating the distribution line L of the annular injection gas flow pressure along the well depth when the casing pressure is equal to the surface opening pressure corresponding to the lowest-stage gas lift valve 1 , calculating the distribution line L of the flow pressure in the tubing along the well depth using the wellhead oil pressure and the density of the oil-gas mixture during normal gas lift production in the tubing 2 , L 1 and L 2 The well depth corresponding to the intersection point of the lines is the perforation depth H to ensure that the gas lift gas does not "short-circuit" through the lowest-stage gas lift valve 2 ;

[0072] Taking Well A as an example, the depth corresponding to the intersection point of the distribution line L of the annular injection gas flow pressure along the well depth 1 and the distribution line L of the flow pressure in the tubing along the well depth 2 is the perforation depth H 2 (see Figure 3 ).

[0073] The calculation method of the flow pressure in the tubing is as follows:

[0074] P yg (H) = P c + 0.000001ρ hh gH;

[0075] Among them, P yg represents the flow pressure in the tubing, MPa; P c represents the wellhead oil pressure, MPa; ρ hh represents the density of the oil-gas mixture in the tubing during normal gas lift production, kg / m 3 , generally taking the value of 150; g represents the acceleration of gravity, m 2 / s, generally taking the value of 9.80; H represents the depth, m;

[0076] The calculation method of the annular injection gas flow gradient is as follows:

[0077] P hk (H) = P t + P g (H) - f g (H);

[0078] Among them, P hk represents the annular flow pressure, MPa; P tDenotes the wellhead casing pressure, in MPa, with a value equal to the surface opening pressure of the lowest-stage gas lift valve; P g Denotes the static gas column pressure, in MPa; f g Denotes the annular gas friction, in MPa, H 2 Denotes the depth, in m;

[0079] Based on the perforation depth H that ensures wellbore integrity 1 And the perforation depth H that ensures the gas lift gas does not "short-circuit" through the lowest-stage gas lift valve 2 , H 1 And H 2 The minimum value of the two is the deepened gas lift perforation depth H js .

[0080] Then, the deepened gas lift perforation depth H is jointly determined based on wellbore integrity and oil production engineering methods. The calculation method for the deepened gas lift perforation depth H is as follows:

[0081] H js = min{H 1 , H 2}.

[0082] In a specific embodiment of the present invention, step 4: Determine the expected increased oil production based on the reservoir elastic productivity and the deepened gas lift perforation depth. Specifically:

[0083] Assume that the well is emptied again at the perforation point H js during the later stage of deepened gas lift. According to the pressure gradient above the perforation point being ▽P 1 and the pressure gradient below the perforation point being ▽P 2 , and the wellhead oil pressure after emptying being P t1 , then the increased oil production N of the deepened gas lift is:

[0084] N = ε * ρ o * [P 1 - (P t1 + ▽P 1 * H js / 100 + ▽P 2 * (H 中 - H js ) / 100)] / B o1 ;

[0085] Among them, N denotes the expected increased oil production of the deepened gas lift, in t; ε denotes the underground elastic productivity, in m 3 / MPa; ρ o denotes the surface crude oil density, in g / cm 3 ; P 1 denotes the formation pressure when the last-stage gas lift valve is emptied, in MPa; P t1It represents the wellhead oil pressure corresponding to the deepened gas lift when the well is emptied, MPa; ▽P 1 It represents the pressure gradient above the perforation point after the perforation point is emptied during deepened gas lift, MPa / 100m, generally taking 0.05; H js It represents the depth of the perforation point during deepened gas lift, m; ▽P 2 It represents the pressure gradient below the perforation point after the perforation point is emptied during deepened gas lift, MPa / 100m, generally taking 0.5; H 中 It represents the mid-depth of the reservoir, m; B o1 It represents the formation oil volume factor at the formation pressure corresponding to the deepened gas lift after the perforation point is emptied.

[0086] Step 5: Based on the expected increased oil production of the deepened gas lift, diagnose the remaining potential after the gas lift well has insufficient liquid supply, including the following steps:

[0087] Calculate the input-output ratio after the gas lift well has insufficient liquid supply based on the expected increased oil production of the deepened gas lift; calculate the input-output ratio according to the input and output of the deepened gas lift measure after the carbonate gas lift well has insufficient liquid supply, and conduct an economic benefit evaluation;

[0088] Diagnose the remaining potential after the gas lift well has insufficient liquid supply based on the water cut, elastic production rate, expected increased oil production and input-output ratio of the gas lift well before the insufficient liquid supply.

[0089] The input-output ratio is calculated as follows:

[0090] R = x * N * (1 - t) / [y 1 * N + y 2 * N + z];

[0091] Among them, R represents the input-output ratio; x represents the crude oil sales price, yuan / t; N represents the expected increased oil production of the deepened gas lift, t; t represents the tax rate, %; y 1 represents the operating cost per ton of oil, yuan / t; y 2 represents the gas lift cost per ton of oil and gas, yuan / t; z represents the cost of the deepened gas lift measure, yuan.

[0092] Comprehensively diagnose the size of the remaining potential according to indicators such as water cut, elastic production rate, expected increased oil production and economic benefit evaluation

[0093] The specific diagnostic criteria are shown in Table 1. The scores of the four indicators are added to obtain the comprehensive score. The range of the indicators is divided according to the on-site production needs, and the scores are assigned according to the contribution of the indicators in different ranges to the economic benefits. For carbonate gas lift wells with a comprehensive score of 0-10 points, the remaining potential is small after insufficient liquid supply and can be scrapped; for carbonate gas lift wells with a score of 10-20 points, the potential is medium after insufficient liquid supply, and measures such as water injection to replace oil, gas injection huff and puff, or intermittent production can be tried to further increase the cumulative production; for carbonate gas lift wells with a score of more than 20 points, the potential is large after insufficient liquid supply, and it can be tried to deepen the gas lift by perforating through the tubing at a reasonable depth below the gas lift valve. The greater the score, the greater the potential.

[0094] Table 1 Remaining Potential Diagnosis Table

[0095]

[0096] The diagnostic method of the present invention has accurate judgment and strong operability. After diagnosis, the success rate of deepening the gas lift for carbonate gas lift wells with large potential after insufficient liquid supply is high. All 12 wells with a comprehensive score of more than 20 points have achieved success through deepening the gas lift, and the success rate is 100%. By deepening the gas lift through perforating through the tubing at a reasonable depth below the gas lift valve after insufficient liquid supply in carbonate gas lift wells, the problem of slow liquid level recovery in water injection to replace oil is avoided, and the problem of high operation cost of replacing the tubing string is solved. Only one perforation through the tubing is required, with low operation cost, high success rate, obvious production increase effect, and high output-input ratio. The method proposed by the present invention not only solves the problem of wellbore integrity that may be brought about by deepening the gas lift, but also maximizes the production increase effect of deepening the gas lift; it not only avoids the problem of small production increase effect due to too shallow perforation depth, but also avoids the problem of technical failure caused by "short circuit" of the gas lift gas from the lowest-stage gas lift valve when the perforation depth is too large.

[0097] Taking Well A where the gas lift has been deepened as an example, this well has a gas lift tubing string. The depth of the lowest-stage gas lift valve is 3501.3 m, and the surface opening pressure of the lowest-stage gas lift valve is 7.77 MPa. In October 2022, this well began to have insufficient liquid supply. Before the insufficient liquid supply, the samples taken for testing did not contain water. The elastic production rate was calculated to be 876 t / MPa, and the comprehensive score in the remaining potential diagnosis table was 42 points, indicating a large potential for deepening the gas lift. In January 2023, this well was deepened by perforating through the tubing 203 m below the lowest-stage gas lift valve (i.e., the vertical depth is 3703.9 m). After perforation, the casing pressure dropped from 7.8 MPa to 4.5 MPa, indicating that the gas lift gas was injected into the tubing from the perforation point and did not "short circuit" from the last-stage gas lift valve. After deepening the gas lift, Well A resumed continuous production. So far, the increased oil production has exceeded 1650 tons, and the output-input ratio has exceeded 3.1.

[0098] The present invention also provides a device for diagnosing the remaining potential after insufficient liquid supply in a gas lift well. The device includes a first determination module for determining the elastic production rate of the reservoir according to the cumulative production of a single well and the formation pressure; a second determination module for determining the deepening gas lift perforation depth according to the wellbore integrity and oil production engineering methods; a calculation module for calculating the expected increased oil production of the deepening gas lift according to the elastic production rate and the deepening gas lift perforation depth; and a diagnosis module for diagnosing the remaining potential after insufficient liquid supply in the gas lift well based on the expected increased oil production of the deepening gas lift.

[0099] The device further includes a determination module, and the steps performed by the determination module include:

[0100] Determining whether the gas lift well has insufficient liquid supply according to the comparison between the surface opening pressure of the lowest-stage gas lift valve in the gas lift well and the casing pressure and the test results of the flow temperature and flow pressure gradient; wherein, when the surface opening pressure of the lowest-stage gas lift valve is less than or equal to a predetermined pressure value, and through the flow temperature and flow pressure gradient test, it is determined that the tubing above the depth of the lowest-stage gas lift valve is in the gas phase and the tubing below is in the oil phase, it is determined that the gas lift well has insufficient liquid supply.

[0101] Regarding the device in the above embodiments, the specific manners in which each module performs operations have been described in detail in the embodiments related to the method, and will not be elaborated here.

[0102] Based on the same inventive concept, an embodiment of the present invention also provides a storage medium, on which a computer program is stored. When the program is executed by a processor, it implements the steps of the refining production plan optimization method in any possible implementation manner described above.

[0103] Optionally, the storage medium may be a non-temporary computer-readable storage medium. For example, the non-temporary computer-readable storage medium may be a ROM, a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, and an optical data storage device, etc.

[0104] Based on the same inventive concept, see Figure 4 , an embodiment of the present invention also provides an electronic device, including a memory 101 (such as a non-volatile memory), a processor 102, and a computer program stored on the memory 101 and executable on the processor 102. When the processor 102 executes the program, it implements the steps of the refining production plan optimization method in any possible implementation manner described above, which is equivalent to the refining production plan optimization device as described above. Of course, the processor can also be used to process other data or perform operations. The electronic device may be a PC, a server, a terminal, or other devices.

[0105] As Figure 4As shown, the electronic device generally may further include: a memory 103, a network interface 104, and an internal bus 105. In addition to these components, other hardware may also be included, which will not be elaborated here.

[0106] It should be noted that the above-mentioned refining production plan optimization device can be implemented by software. As a logically meaningful device, it is formed by the processor 102 of the electronic device where it is located reading the computer program instructions stored in the non-volatile memory into the memory 103 and running them.

[0107] Computer-readable media suitable for storing computer program instructions and data include all forms of non-volatile memory, media, and memory devices, such as semiconductor memory devices (e.g., EPROM, EEPROM, and flash memory devices), magnetic disks (e.g., internal hard disks or removable disks), magneto-optical disks, and CD-ROM and DVD-ROM disks. The processor and the memory may be supplemented by or incorporated into dedicated logic circuits.

[0108] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for diagnosing the remaining potential after insufficient liquid supply in a gas lift well, characterized in that, the method includes, determining the elastic production rate of the reservoir according to the cumulative production of a single well and the formation pressure; determining the deepening gas lift perforation depth according to the wellbore integrity and oil production engineering methods; calculating the expected increased oil production of the deepening gas lift according to the elastic production rate and the deepening gas lift perforation depth; diagnosing the remaining potential after insufficient liquid supply in the gas lift well based on the expected increased oil production of the deepening gas lift.

2. The method for diagnosing the remaining potential after insufficient liquid supply in a gas lift well according to claim 1, characterized in that, before determining the elastic production rate of the reservoir, the method further includes: determining whether there is insufficient liquid supply in the gas lift well according to the comparison between the surface opening pressure of the lowest-stage gas lift valve in the gas lift well and the casing pressure and the test results of the flowing temperature and flowing pressure gradient; wherein, when the surface opening pressure of the lowest-stage gas lift valve is less than or equal to a predetermined pressure value, and through the flowing temperature and flowing pressure gradient test, it is determined that the tubing above the depth of the lowest-stage gas lift valve is in the gas phase and the tubing below is in the oil phase, it is determined that there is insufficient liquid supply in the gas lift well.

3. The method for diagnosing the remaining potential after insufficient liquid supply in a gas lift well according to claim 1, characterized in that, the calculation of determining the elastic production rate of the reservoir according to the cumulative production of a single well and the formation pressure is as follows: ε = N p B o / ρ o / ΔP; Among them, ε represents the elastic productivity of the reservoir, N p represents the cumulative oil production, B o represents the formation volume factor of crude oil, ρ o represents the density of surface crude oil, and △P represents the formation pressure drop value.

4. The method for diagnosing the remaining potential after insufficient liquid supply in a gas lift well according to claim 1, characterized in that, determining the deepening gas lift perforation depth according to the wellbore integrity and oil production engineering methods includes: According to the formation pressure corresponding to different well depths and the external collapse strength of the casing, calculate the external collapse pressure of the casing when the casing pressure is 0, and obtain the perforation depth H 1 ; Using oil production engineering methods, calculate the distribution line L of the annulus injection gas flow pressure along the well depth when the casing pressure is equal to the surface opening pressure corresponding to the lowest-stage gas lift valve 1 , and calculate the distribution line L of the flowing pressure in the tubing along the well depth using the wellhead oil pressure and the density of the oil-gas mixture during normal gas lift production in the tubing 2 , the distribution line L 1 and the distribution line L 2 The well depth corresponding to the intersection point is the perforation depth H 2 ; The punching depth H 1 and the punching depth H 2 The minimum value of the two is the deepened air-lift punching depth H js .

5. The method for diagnosing the remaining potential after insufficient liquid supply in a gas lift well according to claim 4, characterized in that, the calculation method of the flowing pressure distribution in the tubing along the well depth is as follows: P yg (H) = P c + 0.000001 * ρ hh * g * H; Among them, P yg represents the flowing pressure inside the tubing; P c represents the wellhead oil pressure; ρ hh represents the density of the oil-gas mixture inside the tubing during normal gas lift production; g represents the acceleration due to gravity; H represents the depth; the calculation method of the annular gas injection flow gradient along the well depth is as follows: P hk (H) = P t +P g (H) - f g (H); Among them, P hk represents the annular gas injection flow pressure; P t represents the wellhead casing pressure, and its value is equal to the ground opening pressure value of the lowest-stage gas lift valve; P g represents the static gas column pressure; f g represents the annular gas injection friction; H represents the depth; The deepened gas lift perforation depth H js , and the calculation method is as follows: H js = min{H 1 , H 2}.

6. The method for diagnosing the remaining potential after insufficient liquid supply in a gas lift well according to claim 1, characterized in that, the calculation formula for determining the expected increased oil production of the deepening gas lift according to the elastic production rate of the reservoir and the deepening gas lift perforation depth is as follows: N = ε * ρ o * [P 1 - (P t1 + ▽P 1 * H js / 100 + ▽P 2 * (H 中 - H js ) / 100)] / B o1 ; Among them, N represents the expected increased oil production by deepened gas lift; ε represents the underground elastic production rate; ρ o represents the surface crude oil density; P 1 represents the formation pressure corresponding to when the lowest-stage gas lift valve is emptied; P t1 represents the wellhead oil pressure corresponding to when the deepened gas lift is emptied; ▽P 1 represents the pressure gradient above the perforation point after the perforation point of the deepened gas lift is emptied; H js represents the deepening gas lift perforation depth; ▽P 2 represents the pressure gradient below the perforation point after the perforation point of the deepened gas lift is emptied; H 中 represents the mid-depth of the reservoir; B o1 represents the formation crude oil volume factor at the formation pressure corresponding to after the perforation point of the deepened gas lift is emptied.

7. The method for diagnosing the remaining potential after insufficient liquid supply in a gas lift well according to claim 1, characterized in that, diagnosing the remaining potential after insufficient liquid supply in the gas lift well based on the expected increased oil production of the deepening gas lift includes calculating the output-input ratio after insufficient liquid supply in the gas lift well based on the expected increased oil production of the deepening gas lift; diagnosing the remaining potential after insufficient liquid supply in the gas lift well based on the water cut, elastic production rate, expected increased oil production and output-input ratio of the gas lift well before insufficient liquid supply.

8. The method for diagnosing the remaining potential after insufficient liquid supply in a gas lift well according to claim 7, characterized in that, the calculation of the output-input ratio is as follows: R = x * N * (1 - t) / [y 1 * N + y 2 * N + z]; Among them, R represents the output-input ratio; x represents the crude oil selling price; N represents the expected increased oil production by deepening gas lift; t represents the tax rate; y 1 represents the operating cost per ton of oil; y 2 represents the gas lift cost per ton of oil and gas; z represents the cost of the deepening gas lift measure.

9. A device for diagnosing the remaining potential after insufficient liquid supply in a gas lift well, characterized in that, the device includes, a first determination module for determining the elastic production rate of the reservoir according to the cumulative production of a single well and the formation pressure; a second determination module for determining the deepening gas lift perforation depth according to the wellbore integrity and oil production engineering methods; a calculation module for calculating the expected increased oil production of the deepening gas lift according to the elastic production rate and the deepening gas lift perforation depth; a diagnosis module for diagnosing the remaining potential after insufficient liquid supply in the gas lift well based on the expected increased oil production of the deepening gas lift.

10. A device for diagnosing the remaining potential after insufficient liquid supply in a gas lift well according to claim 1, characterized in that, the device further includes a determination module, and the steps executed by the determination module include: determining whether there is insufficient liquid supply in the gas lift well according to the comparison between the surface opening pressure of the bottom-stage gas lift valve in the gas lift well and the casing pressure and the test results of the flow temperature and flow pressure gradient; wherein, when the surface opening pressure of the bottom-stage gas lift valve is less than or equal to a predetermined pressure value, and through the flow temperature and flow pressure gradient test, it is determined that the tubing above the depth of the bottom-stage gas lift valve is in the gas phase and the tubing below is in the oil phase, it is determined that there is insufficient liquid supply in the gas lift well.

11. A storage medium, characterized in that, a program or instructions are stored on the storage medium, and when the program or instructions are run by a processor, the steps of a method for diagnosing the remaining potential after insufficient liquid supply in a gas lift well according to any one of claims 1 to 8 are implemented.

12. An electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, when the processor executes the program, the steps of a method for diagnosing the remaining potential after insufficient liquid supply in a gas lift well according to any one of claims 1 to 8 are implemented.

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