CN-121996878-A - Method, device and equipment for evaluating productivity of carbonate gas field gas well

CN121996878ACN 121996878 ACN121996878 ACN 121996878ACN-121996878-A

Abstract

The specification relates to the technical field of oil and gas exploration and development, in particular to a carbonate gas field gas well productivity evaluation method, device and equipment. The method comprises the steps of drawing a relation chart for measuring different coefficients through collecting historical data in special test wells of carbonate gas wells of different types, classifying the carbonate gas wells according to the drawn relation chart and different reservoir characteristics, fitting coefficient relational expressions of the gas wells of different types, judging the type of the gas wells according to the logging data of the gas wells to be subjected to capacity evaluation, and generating capacity evaluation of the gas wells to be subjected to capacity evaluation. Therefore, on the premise of not developing productivity test wells, the effective evaluation of the productivity of the gas well is realized through an empirical formula and field test data, adverse factors of the productivity test well test can be effectively reduced, and the coverage rate of the productivity evaluation of the gas well is improved.

Inventors

CAI JUNJUN
ZHANG LIANJIN
LIU WEI
ZHANG FEI
JIANG JUN
XU RUI

Assignees

中国石油天然气股份有限公司

Dates

Publication Date: 20260508
Application Date: 20241106

Claims (13)

1. A carbonate gas field gas well capacity evaluation method, the method comprising: Acquiring logging history data of a plurality of types of carbonate gas field gas wells, and acquiring logging stratum coefficients and logging energy storage coefficients according to the logging history data; Obtaining a binomial productivity equation coefficient according to the logging history data; drawing a first relation chart of the well logging formation coefficient and the binomial productivity equation coefficient, and a second relation chart of the well logging energy storage coefficient and the well logging formation coefficient; classifying the carbonate gas field gas wells according to the distinguishing characteristics of the first relationship chart and the second relationship chart; Fitting first relation formulas of different types of logging stratum coefficients and binomial productivity equation coefficients respectively according to the classification results; Logging data of a gas well to be evaluated for productivity is obtained, wherein the logging data comprises logging stratum coefficients and logging energy storage coefficients, and original stratum pressure of the gas well to be evaluated for productivity is obtained through static pressure testing before production operation of the gas well to be evaluated for productivity; Judging the corresponding type of the well to be subjected to productivity evaluation according to the well logging data of the well to be subjected to productivity evaluation, substituting the well logging stratum coefficient into a first relational expression corresponding to the corresponding type of the well to be subjected to productivity evaluation, and determining a binomial productivity equation coefficient of the well to be subjected to productivity evaluation; Substituting the binomial productivity equation coefficient of the gas well to be evaluated for productivity and the original stratum pressure thereof into a gas well productivity calculation formula of the gas field to generate productivity evaluation of the gas well to be evaluated for productivity.
2. The method of evaluating capacity of a carbonate gas field gas well of claim 1, wherein obtaining a binomial capacity equation coefficient from the well test logging history data further comprises, The coefficients of the binomial productivity equation are respectively: Wherein A represents a stable Darcy seepage term coefficient of the gas well, mu g is gas viscosity, Z represents a deviation factor, T represents temperature, r represents well radius, subscript w represents a borehole, subscript e represents a gas release zone, S represents a skin factor, B represents a stable non-Darcy seepage term coefficient of the gas well, K represents gas reservoir permeability, h is reservoir thickness, and D represents a non-Darcy seepage coefficient.
3. The method of evaluating capacity of a carbonate gas field gas well of claim 2, wherein plotting the first relationship between the well logging formation coefficients and the binomial capacity equation coefficients further comprises, The first relationship plate is expressed as: A=a(Kh) b , B=a'(Kh) b ', In the formula, A represents a gas well stable Darcy seepage term coefficient, B represents a gas well stable non-Darcy seepage term coefficient, kh represents a gas well logging stratum coefficient, and a, a ', B and B' represent fitting empirical numbers.
4. The method of evaluating capacity of a carbonate gas field gas well of claim 1, wherein the second relationship graph of the well test log energy storage coefficient and the well test log formation coefficient further comprises, The second relationship plate is expressed as: Kh=c(φh) 2 +d(φh), Wherein c and d are fitting experience numbers, and phi h is a logging energy storage coefficient.
5. The method of evaluating capacity of a carbonate gas field gas well according to claim 4, wherein the pre-production static pressure test performed on the gas well to be evaluated for capacity further comprises, Recording the stopping point depth and pressure data in the well shaft of the gas well to be subjected to capacity evaluation through a pressure gauge, and converting the stopping point depth into stopping point vertical depth; And according to the pressure gradient of the last two stopping points of the stopping point vertical depth fitting shaft, calculating the middle pressure of the production layer of the gas well to be subjected to productivity evaluation according to the pressure gradient, and recording the middle pressure as the original stratum pressure.
6. The method of evaluating capacity of a carbonate gas field gas well of claim 5, wherein fitting a pressure gradient of a last two stops of the wellbore according to the stop vertical depth further comprises, The number of the stopping points in the well shaft of the gas well to be subjected to productivity evaluation is n, the vertical depth of the n-1 th stopping point is recorded as H 1 , the vertical depth of the n-1 th stopping point is recorded as H 2 , the pressure of the n-1 th stopping point is recorded as p 1 , the pressure of the n-1 th stopping point is recorded as p 2 , and the pressure gradient calculation formula is as follows: Wherein Δp is the pressure gradient, p 1 is the pressure score of the n-1 th stop point, p 2 is the pressure of the n-1 th stop point, H 1 is the vertical depth of the n-1 th stop point, and H 2 is the vertical depth of the n-th stop point.
7. The method of evaluating the capacity of a carbonate gas field gas well of claim 6 wherein calculating the production zone mid-zone pressure of the gas well to be evaluated as the raw formation pressure based on the pressure gradient further comprises, The calculation formula of the pressure in the middle of the gas well production layer is as follows, p=p 2 +(H-H 2 )Δp, Wherein p is the pressure in the middle of the gas well production zone, p 2 is the pressure at the nth stop, H is the vertical depth in the middle of the gas well production zone, H 2 is the vertical depth at the nth stop, and Δp is the pressure gradient.
8. The method of evaluating the capacity of a hydrocarbon well in a carbonate gas field according to claim 7, wherein substituting the logging formation factor into the first relation corresponding to the type of hydrocarbon well to be evaluated for capacity further comprises, If the logging stratum coefficients of the to-be-produced capacity evaluation gas well lack in logging data, respectively fitting second relation formulas of logging energy storage coefficients of logging of different types and logging stratum coefficients of logging of different types according to classification results; Substituting the logging energy storage coefficient of the gas well to be subjected to productivity evaluation into the second relation to obtain the logging stratum coefficient of the gas well to be subjected to productivity evaluation.
9. The method for evaluating capacity of a carbonate gas field well according to claim 8, wherein the gas field well capacity calculation formula is, Where q AOF represents the well stable absolute unobstructed flow and P R represents the original formation pressure.
10. A carbonate gas field gas well productivity evaluation device, the device comprising: The historical data processing module is used for acquiring well testing and logging historical data of various carbonate gas field gas wells and acquiring well testing and logging stratum coefficients and well testing and logging energy storage coefficients according to the well testing and logging historical data; Obtaining a binomial productivity equation coefficient according to the logging history data; The relation chart drawing module is used for drawing a first relation chart of the well logging stratum coefficient and the binomial productivity equation coefficient and a second relation chart of the well logging energy storage coefficient and the well logging stratum coefficient; the gas field gas well classification module is used for classifying the carbonate gas field gas wells according to the distinguishing characteristics of the first relation chart and the second relation chart; The coefficient relation fitting module is used for respectively fitting first relation formulas of different types of well logging stratum coefficients and binomial productivity equation coefficients according to the classification result; the gas well static pressure test module is used for acquiring logging data of a gas well to be evaluated for productivity, and comprises logging stratum coefficients and logging energy storage coefficients, and acquiring original stratum pressure of the gas well to be evaluated for productivity by static pressure test before production operation; The productivity coefficient acquisition module is used for judging the type corresponding to the logging data of the gas well to be evaluated according to the logging data of the gas well to be evaluated, substituting the logging stratum coefficient into a first relational expression corresponding to the type corresponding to the gas well to be evaluated, and determining a binomial productivity equation coefficient of the gas well to be evaluated; And the gas well productivity evaluation module is used for substituting the binomial productivity equation coefficient of the gas well to be evaluated and the original stratum pressure into a gas well productivity calculation formula of the gas well to be evaluated to generate productivity evaluation of the gas well to be evaluated.
11. A computer device comprising a memory, a processor, and a computer program stored on the memory, characterized in that the processor implements the method of any of claims 1 to 9 when executing the computer program.
12. A computer readable storage medium, characterized in that the computer readable storage medium stores a computer program which, when executed by a processor, implements the method of any one of claims 1 to 9.
13. A computer program product, characterized in that the computer program product comprises a computer program which, when executed by a processor, implements the method of any one of claims 1 to 9.

Description

Method, device and equipment for evaluating productivity of carbonate gas field gas well Technical Field The specification belongs to the technical field of oil and gas exploration and development, and particularly relates to a carbonate gas field gas well productivity evaluation method, device and equipment. Background Carbonate rock large gas field is one of the important fields of Chinese natural gas exploration and development. By the end of 2018, the carbonate rock reserve accounts for 28.34% of the large gas field reserve, and 66% of the conventional gas yield in 2018 is produced by the carbonate gas field. In the carbonate atmosphere field discovered in recent years, low permeability is a typical feature of gas reservoirs. The absolute unimpeded flow q AOF of the gas well is determined to be the core work of gas field development, q AOF in the early evaluation process is the basis of the design of the gas production engineering and the ground centralized transportation engineering throughout the gas field development, the reliability degree of the evaluation result determines the rationality of the engineering design and investment, and q AOF in the stable yield and the decreasing period is the basis of the optimization and adjustment of the yield of the gas field. The determination of the carbonate gas field q AOF is based on the capacity testing technology based on seepage mechanics, the capacity testing is initially a multi-point testing method, through decades of mine practice, with the deep concepts of protecting resources, protecting environment, improving safety, improving management efficiency and the like, more single-point testing methods are used and used in the field-implemented capacity evaluation and gas well production determination process, since the "one-point method" formula established based on binomial capacity equation theory in 1989 is disclosed, the method gradually becomes a main method of a single-point testing method of the mine due to the fact that the method integrates theories, experience and convenience, and a large number of single-point testing capacity evaluation empirical formulas are successively established for each gas field. Carbonate gas fields generally have the characteristics of compact matrix, crack development and strong heterogeneity, and along with continuous practice of single-point testing of the mine, gas wells with low permeability, strong heterogeneity and medium-high permeability geological features show contradiction with 'one-point method' mismatch in the productivity evaluation process. If the reservoir seepage capability is strong, the stable experience number in the formula of one-point method is smaller than 0.25, and the productivity evaluation result of the single-point test of the gas reservoir under the small production pressure difference is amplified by times and is not applicable to the one-point method. The above problems can be summarized and simplified to derive a form of "one-point" production equation based on the more reliable production results obtained for a particular block. If the matching relation of holes, holes and slits of different dimensions of the gas reservoir is complex, the low permeability and the strong non-uniformity are presented, the orders of the permeability of each well area are different after the reservoir is transformed, the single-point test result of the gas well cannot reflect the actual stable seepage potential, and the on-site well test of the gas reservoir is difficult to meet the well test technology of the natural gas well. In addition, the well testing risk of deep to ultra-deep carbonate gas fields is high, and the universality of the expansion 'one point method' for finely dividing reservoir types based on dynamic and static data is limited. Therefore, how to evaluate the productivity of a carbonate gas field gas well and finely divide the reservoir types based on dynamic and static data is a technical problem to be solved urgently at present. Disclosure of Invention In order to solve the problem that a high-consequence area is difficult to re-identify in the prior art, the embodiment of the specification provides a method, a device and equipment for evaluating the productivity of a carbonate gas well, and to solve the problem that the conventional 'one-point method' is low in reliability of the productivity evaluation result of a low-permeability, high-non-uniformity and medium-high-permeability reservoir gas well, a simple method for calculating stable productivity based on logging data is provided, and the quantitative relation between the stable productivity of the carbonate gas well and logging stratum coefficients and energy storage coefficients is described. The specification establishes a method for calculating the gas well stability q AOF based on logging Kh and phi h, and the method defines mathematical expressions of gas well stability q AOF of different types of reservoir characteris