CN-121997789-A - Sand production prediction method and system for ultra-deep ultra-high pressure fracture low Kong Shayan gas reservoir gas well

CN121997789ACN 121997789 ACN121997789 ACN 121997789ACN-121997789-A

Abstract

The invention belongs to the technical field of gas reservoir development, and discloses a method and a system for predicting sand production of a gas reservoir well with ultra-deep ultra-high pressure crack property low Kong Shayan, wherein the prediction method assumes that a plastic region exists in surrounding rock of a well to be detected, and the plastic region is of an elliptic structure; the method comprises the steps of obtaining the length of a long half shaft of a plastic region of an elliptical structure by utilizing the obtained radius of the well bore, the cohesive force of the rock, the internal friction angle of the rock, the bottom hole pressure, the maximum horizontal ground stress and the minimum horizontal ground stress of the well bore to be measured, combining a pre-constructed projection model of the plastic region of the elliptical structure, comparing the length of the long half shaft with the radius of the well bore, and determining whether the well bore to be measured produces sand or not; and when the well to be tested is sanded, acquiring the radius of the plastic region by using a pre-constructed radius model of the plastic region, and finishing the sand production prediction of the ultra-deep ultra-high pressure crack low Kong Shayan gas reservoir gas well. The prediction result of the method is accurate and reliable.

Inventors

CHEN DONG
REN LONG
YANG FENGLAI
CHEN NAIDONG
CHEN MINGQIANG
LI HAIMING
SUN JIAN
DING HAIYAN
ZHANG WUGANG
ZHANG HAO

Assignees

中国石油天然气股份有限公司

Dates

Publication Date: 20260508
Application Date: 20241107

Claims (10)

1. The sand production prediction method of the ultra-deep ultra-high pressure fracture low Kong Shayan gas reservoir gas well is characterized by comprising the following steps of: Acquiring a well bore radius, a rock cohesive force, a rock internal friction angle, a bottom hole pressure, a maximum horizontal ground stress and a minimum horizontal ground stress of a well bore to be measured, and assuming that a plastic region exists in surrounding rock of the well bore to be measured, wherein the plastic region is of an elliptic structure; The method comprises the steps of obtaining the length of a long half shaft of an elliptic structure plastic region by utilizing the obtained borehole radius, rock cohesive force, rock internal friction angle, bottom hole pressure, maximum horizontal ground stress and minimum horizontal ground stress of a borehole to be measured and combining a pre-constructed elliptic structure plastic region projection model, and comparing the length of the long half shaft with the borehole radius to determine whether the borehole to be measured produces sand or not; And when the well to be tested is sanded, acquiring a plastic region radius by using a pre-constructed plastic region radius model, and finishing the sand production prediction of the ultra-deep ultra-high pressure crack low Kong Shayan gas reservoir gas well.
2. The ultra-deep ultra-high pressure fracture low Kong Shayan gas reservoir gas well sand production prediction method according to claim 1, wherein the length of the long half shaft is compared with the radius of the well bore to determine whether the well bore to be detected produces sand, and then the prediction result is compared by using a combined modulus method, and when the comparison result is consistent, the plastic region radius is obtained by using a pre-constructed plastic region radius model, so that the ultra-deep ultra-high pressure fracture low Kong Shayan gas reservoir gas well sand production prediction is completed.
3. The ultra-deep ultra-high pressure fracture low Kong Shayan gas reservoir gas well sand production prediction method according to claim 1, wherein the pre-built elliptic structure plastic region projection model is: Wherein, the For the maximum horizontal ground stress to be the highest, To be a minimum of the horizontal ground stress, For the purpose of the cohesive force of the rock, Is the internal friction angle of the rock, Is the bottom hole pressure.
4. The method for predicting sand production of a gas reservoir with ultra-deep and ultra-high pressure crack nature low Kong Shayan as claimed in claim 1, wherein the method is characterized in that a pre-built elliptic structure plastic region projection model is combined to obtain the length of a major half axis of an elliptic structure plastic region, specifically, when b >0, the length of the major half axis of the ellipse is as follows When b <0, the major half axis of the ellipse is 。
5. The ultra-deep ultra-high pressure crack nature low Kong Shayan gas reservoir gas well sand production prediction method according to claim 1 is characterized in that the length of the long half shaft is compared with the radius of the well bore to determine whether the well bore to be detected produces sand, specifically, when the length of the long half shaft is larger than the radius of the well bore, a plastic zone appears near the well wall, sand production in the well is performed, otherwise, no plastic zone appears near the well wall, and sand production in the well is not performed.
6. The ultra-deep ultra-high pressure fracture low Kong Shayan gas reservoir gas well sand production prediction method according to claim 1, wherein the pre-constructed plastic region radius model is: in the formula, Is the radius of the plastic region, Is the radius of the borehole.
7. The utility model provides a sand prediction system of ultra-deep ultra-high pressure crack nature low Kong Shayan gas reservoir gas well, its characterized in that includes: The data acquisition module is used for acquiring the radius of the well bore, the cohesive force of the rock, the internal friction angle of the rock, the bottom hole pressure, the maximum horizontal ground stress and the minimum horizontal ground stress of the well bore to be tested, and assuming that a plastic area exists in the surrounding rock of the well bore to be tested, wherein the plastic area is of an elliptic structure; The first data processing module is used for acquiring the length of a long half shaft of the plastic region of the elliptical structure by utilizing the acquired borehole radius, rock cohesive force, rock internal friction angle, bottom hole pressure, maximum horizontal ground stress and minimum horizontal ground stress of the borehole to be detected and combining a pre-constructed projection model of the plastic region of the elliptical structure, and comparing the length of the long half shaft with the borehole radius to determine whether the borehole to be detected produces sand; and the second data processing module is used for acquiring the plastic region radius by utilizing a pre-constructed plastic region radius model when the well to be tested is sanded, so as to finish the sand production prediction of the ultra-deep ultra-high pressure fractured low Kong Shayan gas reservoir gas well.
8. A computer device comprising a memory, a processor and a computer program stored on the memory, characterized in that the processor executes the computer program to carry out the steps of the method according to any one of claims 1-6.
9. A computer readable storage medium storing a computer program, characterized in that the computer program/instructions, when executed by a processor, implement the steps of the method according to any one of claims 1-6.
10. A computer program product comprising computer programs/instructions which, when executed by a processor, implement the steps of the method according to any one of claims 1 to 6.

Description

Sand production prediction method and system for ultra-deep ultra-high pressure fracture low Kong Shayan gas reservoir gas well Technical Field The invention belongs to the technical field of gas reservoir development, and relates to a sand production prediction method and system for a gas reservoir gas well with ultra-deep and ultra-high pressure crack property of low Kong Shayan. Background During the exploitation of sandstone gas reservoirs, a large amount of sand is produced due to formation softness or exploitation factors, and the like, so that great harm is brought to the exploitation of gas wells, sand particles can be precipitated at the bottom of the wells to form sand plugs, and the gas wells are reduced in production or even stopped in production. The sand-containing fluid has strong erosion, stratum sand carried by high-speed gas can aggravate abrasion of underground equipment and ground equipment, and more serious, under the condition of long-term sand production, the casing is provided with a huge cavity, internal and external stress is unbalanced, the stratum can suddenly collapse, the casing is reduced in diameter and deformed if the stratum is light, the casing is broken and crushed if the stratum is heavy, a gas well is scrapped, and safe and stable production of a gas field is seriously affected. Many factors affect the sand production of gas wells, and three general categories of ① geomechanical factors can be outlined. Including in situ stress conditions (vertical and original horizontal), pore pressure, in situ temperature, geologic formations, etc., ② the overall properties of the sandstone reservoir. Well depth, strength and deformation characteristics of sandstone, porosity, permeability, drainage radius, composition of fluids (oil, gas, water content and distribution, etc.), clay content, rock composition, particle size and shape, compaction (cementing) conditions, etc., ③ engineering process factors. Including completion type, wellbore structural parameters (wellbore depth, wellbore deviation, azimuth, wellbore diameter), completion/fracturing fluid properties, stimulation (fracturing, acidizing, etc.), production process parameters (flowback regime, production flow rates, differential pressure, flow rates), gas layer damage (skin factor increase), well shut-in schemes, artificial lift techniques, gas reservoir depletion, cumulative sand production, etc. The comprehensive properties of the geomechanical factors and the sandstone reservoir are natural factors, and engineering process factors (well completion factors and exploitation factors) are artificial factors. The geological conditions of the ultra-deep ultra-high pressure fractured low-hole sandstone gas reservoir are affected by multi-stage complex structural motions, the regional structural zones have micro-fractures and fault development, the reservoir space types are various, and the geological engineering conditions are extremely complex. When the sand production of the gas reservoir gas well is predicted at present, in order to reduce the difficulty of prediction, the rock of the well wall is set to be in a complete elastic state, and the plastic area of the well wall is not considered, so that the predicted condition and the actual condition have certain access, the accuracy of the prediction is further influenced, and an accurate reference basis is difficult to provide for the sand production prediction of the actual site. Disclosure of Invention Aiming at the problems in the prior art, the invention provides a method and a system for predicting sand production of a gas well of an ultra-deep and ultra-high pressure fracture low Kong Shayan gas reservoir, so as to solve the technical problem of poor accuracy in predicting sand production of the gas well in the prior art. The invention is realized by the following technical scheme: A sand production prediction method of an ultra-deep ultra-high pressure fracture low Kong Shayan gas reservoir gas well comprises the following steps: Acquiring a well bore radius, a rock cohesive force, a rock internal friction angle, a bottom hole pressure, a maximum horizontal ground stress and a minimum horizontal ground stress of a well bore to be measured, and assuming that a plastic region exists in surrounding rock of the well bore to be measured, wherein the plastic region is of an elliptic structure; The method comprises the steps of obtaining the length of a long half shaft of an elliptic structure plastic region by utilizing the obtained borehole radius, rock cohesive force, rock internal friction angle, bottom hole pressure, maximum horizontal ground stress and minimum horizontal ground stress of a borehole to be measured and combining a pre-constructed elliptic structure plastic region projection model, and comparing the length of the long half shaft with the borehole radius to determine whether the borehole to be measured produces sand or not; And when the well to be tested i