CN112780265B - Simulation device for hydraulic fracturing test of crushed soft coal layer - Google Patents
Simulation device for hydraulic fracturing test of crushed soft coal layer Download PDFInfo
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- 238000012360 testing method Methods 0.000 title claims abstract description 43
- 238000004088 simulation Methods 0.000 title claims abstract description 37
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- 239000012530 fluid Substances 0.000 claims abstract description 16
- 238000012544 monitoring process Methods 0.000 claims description 5
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- 229910052602 gypsum Inorganic materials 0.000 description 1
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B49/00—Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/25—Methods for stimulating production
- E21B43/26—Methods for stimulating production by forming crevices or fractures
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/30—Specific pattern of wells, e.g. optimising the spacing of wells
- E21B43/305—Specific pattern of wells, e.g. optimising the spacing of wells comprising at least one inclined or horizontal well
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Abstract
The invention relates to the technical field of coal mining simulation experiments, in particular to a simulation device for hydraulic fracturing test of a crushed soft coal layer, which comprises: a fracturing sample configured to have a coal seam roof layer, a coal seam interface layer, and a coal seam; a simulated wellbore disposed within the roof layer of the coal seam; the true triaxial physical simulation experiment machine is used for loading simulated three-dimensional ground stress on the fracturing sample placed in the triaxial loading chamber; a hydraulic fracturing servo pump pressure control system for injecting fracturing fluid into the simulated wellbore to simulate a hydraulic fracturing process; the relation between the depth of the horizontal section and the coal seam cracks, the relation between the distribution and the spacing of the perforations and the coal seam cracks, and the relation between the existence position and the direction of the natural cracks on the coal seam cracks can be obtained, and meanwhile, the weight of the influence factors on the cracks can be obtained, so that the efficient extraction of the coal seam gas is guided, and the production direction is improved.
Description
Technical Field
The invention relates to the technical field of coal bed gas exploitation simulation tests, in particular to a hydraulic fracturing test of a crushed soft coal bed, and particularly relates to a simulation device for hydraulic fracturing test of the crushed soft coal bed.
Background
The basic principle of hydraulic fracturing is to pump a large amount of high-pressure liquid mixed with propping agent into a reservoir through a shaft, so that the reservoir is forced to be broken to form artificial cracks, the propping agent is filled into the cracks, and the pore-permeability characteristic of the reservoir is improved.
Broken soft low-permeability coal beds are always regarded as forbidden areas for ground coal bed gas extraction, the overall single well yield of the fracturing vertical well is low, the stable production period is short, the attenuation is fast, the extraction rate is low, and the extraction technology has not been broken through. Therefore, in the prior art, aiming at the characteristics of the crushed soft low-permeability coal bed, a sample model of a roof-coal bed-bottom plate is established, and a horizontal well is arranged in a roof rock stratum close to the coal bed to carry out a hydraulic fracturing test. The length of the crack formed in the underlying crushed soft hypotonic coal seam is longer than that of the crack formed by directly carrying out hydraulic fracturing in the crushed soft hypotonic coal seam, the fracturing transformation effect is better, and the possibility that the roof hydraulic fracturing crack passes through a coal-rock interface and enters the coal seam is proved.
In practical construction, how to determine the distance between the horizontal well and the coal seam so that the horizontal well can obtain the position of the optimal fracture is needed to be known at present, so that a simulation experiment device is needed to search the relationship between different distances between the horizontal well and the coal seam and the generated fracture effect so as to assist in determining the optimal well position arrangement scheme of the horizontal well in practical extraction construction.
Prior art literature:
physical simulation system and method for crack propagation in CN 105756645A-shale in patent document 1
Disclosure of Invention
The invention aims to provide a simulation device for hydraulic fracturing test of a crushed soft coal layer, which can obtain the relation between a horizontal well and a coal seam and generated cracks when the horizontal well and the coal seam are at different intervals in a simulation experiment of hydraulic fracturing so as to prove whether an optimal well position arrangement interval exists.
The invention provides a simulation device for hydraulic fracturing test of a crushed soft coal layer, which comprises the following components:
a fracturing sample configured to have a coal seam roof layer, a coal seam interface layer, and a coal seam;
a simulated wellbore disposed within the roof layer of the coal seam;
the true triaxial physical simulation experiment machine is used for loading simulated three-dimensional ground stress on the fracturing sample placed in the triaxial loading chamber;
a hydraulic fracturing servo pump pressure control system for injecting fracturing fluid into the simulated wellbore to simulate a hydraulic fracturing process;
the fracturing process monitoring system is used for detecting and recording the state of a fracture of a fracturing sample in the hydraulic fracturing process;
the simulation well comprises a vertical section and at least two horizontal sections with preset intervals in the height direction, and the horizontal sections of a plurality of simulation wells are provided with the same jet holes.
Preferably, the height difference and the length between the horizontal sections of the plurality of simulated wells are the same, and the included angle between the connecting line of the midpoints of each horizontal section and the vertical section is 75-85 degrees.
Preferably, the horizontal segment is provided with a plurality of jet holes which are uniformly distributed and have equal sizes.
Preferably, a plurality of jet holes are arranged right below the horizontal section and are arranged in a straight shape and unevenly distributed.
Preferably, the plurality of jet holes are divided into clusters and arranged on the cambered surface of the lower half part of the horizontal section.
Preferably, each shower of orifices contains 3 orifices with a 60 ° spacing between the orifices, or each shower of orifices contains 5 orifices with a 30 ° spacing between the orifices.
Preferably, one of the horizontal sections is provided with a fracturing flap plate, and the fracturing flap plate comprises a pressure receiving plate positioned in a simulated well bore channel and a seam making part extending out of the simulated well bore; the pressure receiving plate is fixedly connected with the joint making part and is rotationally connected relative to the simulated well bore, so that the joint making part can make cracks in a fracturing sample when the fracturing fluid flows in the simulated well bore channel to be subjected to the pressure receiving plate.
Preferably, the seam making portion extends out of the simulated wellbore through the jet aperture.
Preferably, the seam making part is provided with a flat tip parallel to the radial or axial direction of the horizontal section.
Preferably, the pressure receiving plate and the joint making part have an included angle in a radial plane, the pressure receiving plate is inclined to the fluid inflow direction, and a limiting block for limiting the overturning angle of the pressure receiving plate is arranged on the inner wall of the simulated shaft.
It should be understood that all combinations of the foregoing concepts, as well as additional concepts described in more detail below, may be considered a part of the inventive subject matter of the present disclosure, provided that such concepts are not mutually inconsistent. In addition, all combinations of claimed subject matter are considered part of the disclosed inventive subject matter.
The foregoing and other aspects, embodiments, and features of the present teachings will be more fully understood from the following description, taken together with the accompanying drawings. Other additional aspects of the invention, such as features and/or advantages of the exemplary embodiments, will be apparent from the description which follows, or may be learned by practice of the embodiments according to the teachings of the invention.
Drawings
The drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures may be represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. Embodiments of various aspects of the invention will now be described, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a schematic illustration of a simulated wellbore placed in a simulated test specimen in a simulated device for hydraulic fracturing testing of a crushed soft coal seam in accordance with the present invention;
FIG. 2 is a schematic diagram of a simulated wellbore in a simulation apparatus for hydraulic fracturing testing of a crushed soft coal seam in accordance with the present invention;
FIG. 3 is a schematic cross-sectional structural view of jet hole distribution in a simulation device for hydraulic fracturing test of a crushed soft coal layer according to the invention;
FIG. 4 is a schematic diagram of the configuration of jet hole distribution in the simulation device for hydraulic fracturing test of crushed soft coal layers according to the present invention;
FIG. 5 is a schematic diagram of the structure of a fracture flap in the simulation device for hydraulic fracture testing of a crushed soft coal layer according to the present invention;
fig. 6 is a schematic diagram of another structure of a fracture flap in the simulation device for hydraulic fracture testing of a crushed soft coal layer.
Detailed Description
For a better understanding of the technical content of the present invention, specific examples are set forth below, along with the accompanying drawings.
Aspects of the invention are described in this disclosure with reference to the drawings, in which are shown a number of illustrative embodiments. The embodiments of the present disclosure are not necessarily intended to include all aspects of the invention. It should be understood that the various concepts and embodiments presented above, as well as those described in more detail below, may be implemented in any of a number of ways with a simulation apparatus for hydraulic fracture testing of a crushed soft coal layer, as the disclosed concepts and embodiments are not limited to any implementation. Additionally, some aspects of the present disclosure may be used alone or in any suitable combination with other aspects of the present disclosure.
The horizontal well is fractured in a roof stratum close to the coal seam, and the fracture can be extended and penetrated in a vertical direction from the roof stratum with a high stress value to the crushed soft hypotonic coal seam with a lower stress value; in the direction of the maximum horizontal principal stress, the fracture is easy to transversely extend in the roof strata to form a long fracture due to the concentration of the tip stress of the fracture of the relatively fragile roof strata, and the fracture also downwards tears the underlying relatively plastic crushed soft hypotonic coal seam to form a longer hydraulic fracture while transversely extending. That is, the tear generated by the transverse extension of the seam of the overlying strata fracture forms a longer hydraulic fracture in the underlying crushed soft hypotonic coal seam. However, it has not been possible to determine at what depth in the roof formation the horizontal well is at, the maximum fracture is created, or the relationship between the placement of the horizontal well and the fracture created in the coal seam.
The invention aims to realize that the simulated well bore is provided with the horizontal sections with different distances from the coal seam, and can obtain the generated crack data of the simulated well bore at different depths in a fracturing test, so that a tester is helped to obtain the relation between the arrangement position of the simulated well bore and the generated cracks in the coal seam.
The embodiment provides a simulation device for hydraulic fracturing test of a crushed soft coal layer, which comprises a fracturing sample, a simulated wellbore, a true triaxial physical simulation experiment machine, a hydraulic fracturing servo pump pressure control system and a fracturing process monitoring system.
As shown in fig. 1 and 2, in order to make the fracturing samples representative, samples are collected on coal seam and roof rock and rock coal interfaces, parameters including compressive strength, elastic modulus, poisson ratio and the like are obtained through rock mechanical tests, a sample model is constructed, and the fracturing samples are constructed to have a coal seam roof layer 100, a coal seam interface layer 200 and a coal seam 300 by combining physical and mechanical properties of the coal seam and the roof thereof and coal rock interface properties.
In this embodiment, the roof layer 100 is made of fine sand and cement, the boundary layer 200 is made of gypsum, fine sand and cement, the coal layer 300 is made of coal dust, fine sand and cement, and the fracturing sample is formed into a 300 mm-300 mm cube, and the height ratio of the roof layer 100, the boundary layer 200 and the coal layer 300 is 6:1:3.
Further, a pseudo-well bore is provided in the seam roof layer 100, the pseudo-well bore comprising a vertical section 11 and at least two horizontal sections 12 having a predetermined spacing in the height direction, the horizontal sections 12 of a plurality of pseudo-wells being provided with identical jet holes 2.
In this embodiment, the diameter of the simulated wellbore is set to be a steel pipe with an outer diameter of 8mm and an inner diameter of 6mm, and is set to be a stepped shape as shown in fig. 1 and 2, and the diameter of the jet hole 2 is 2mm, wherein the length of the horizontal section is 50mm, the length of the vertical section 11 is 160mm, the interval between the lowest horizontal section and the coal seam boundary layer 200 is 10mm, and the interval between the adjacent horizontal sections 12 is 10mm.
Further, the height differences and lengths between the horizontal sections 12 of the plurality of simulated wells are the same, and in alternative embodiments, the height differences between the horizontal sections 12 are replaced with different spacing, such as a larger 10mm spacing fracture gap, depending on the test results, and may be replaced with a 5mm spacing test, wherein the angle between the line at the midpoint of each horizontal section 12 and the vertical section 11 is maintained at 75-85 °.
Thus, the horizontal sections 12 with different intervals with the coal seam boundary layer 200 are constructed in the coal seam roof layer 100, after the hydraulic fracturing test, the relation between the horizontal well and the cracks at different positions away from the coal seam can be known through analysis of the formed cracks, so that the horizontal well is constructed at a proper depth in actual exploration, and the cracks with large extraction quantity are obtained.
Further, the manufactured fracturing sample is placed into a triaxial loading chamber in a true triaxial physical simulation experiment machine, and the fracturing sample is loaded by simulating three-dimensional ground stress; the ground stress loading is carried out by an electrohydraulic servo device consisting of a hydraulic power pump group, and pressure can be independently applied to 3 groups of vertical surfaces of the cube test piece to simulate the ground stress state.
Further, a hydraulic fracturing servo pump pressure control system is used for injecting fracturing fluid into the simulated well bore to simulate a hydraulic fracturing process; the pumping fracturing fluid simulation can be realized by pumping high-pressure fracturing fluid into a simulated well bore by a gas-water separation servo high-pressure pump, and can work at constant displacement or perform fluid pumping according to a preset pumping program. The control system and the measuring system are directly controlled by the main control computer, and data such as displacement, water injection pressure and the like in the whole process of the test are automatically collected.
In order to detect the formation change state and the formed morphology of the fracture in the fracturing process, a fracturing process monitoring system is provided for detecting and recording the fracture state of the fracturing sample in the hydraulic fracturing process. The method comprises the steps of acquiring and analyzing acoustic signals emitted in the crack formation process to locate crack information in a three-dimensional space, and judging the crack initiation position and the crack extension direction of a crack; and simultaneously, after the fracturing test, scanning and destroying the crack propagation condition inside the sample by using laser scanning equipment, and observing the conditions of expansion, penetration and macroscopic damage caused by the initial damage of microcracks, holes and the like under the hydraulic fracturing action.
Specifically, the acoustic positioning analysis device uses an acoustic emission probe, the acoustic emission receiving device is arranged at eight vertexes of the fracturing test sample to form acoustic emission three-dimensional space positioning monitoring, and acoustic emission events can be monitored and recorded.
Therefore, the acoustic emission probe is utilized to receive acoustic emission signals generated when the fracturing sample is cracked, and further the distribution of acoustic emission events in the whole fracturing sample space can be monitored, and the number of the acoustic emission events is related to the size and the number of the fracturing cracks. The crack morphology and trend can be determined according to the density of the distribution of acoustic emission events, and the determination is usually real-time information obtained by adopting a corresponding program.
Further, a laser scanner is used for carrying out fault scanning on the fractured sample to obtain a simulated graph of the fracture in the sample so as to show the characteristics of the fracture length, the fracture height and the fracture width of the fracture, and the difference of the fracture formed under each horizontal section 12 is intuitively observed to judge the relationship between the horizontal well and the fracture length, the fracture height and the fracture width when the horizontal well is at different positions from the coal seam.
Example 1: the horizontal section 12 is provided with five jet holes 2 which are uniformly distributed and equal in size, the five jet holes 2 are arranged under the horizontal section 12 and are arranged in a straight shape, the diameter of each jet hole 2 is 2mm, the distance between the jet holes 2 is 7mm, the distance between the jet holes 2 at two ends is 7mm from the two ends of the horizontal section 12, in a fracturing test, fracturing fluid flows out of the jet holes 2, a certain pressure is obtained under the horizontal section 12 by a nearby test block stratum, and when a hydraulic fracturing servo pump pressure control system continuously pressurizes until the position reaches the minimum horizontal stress of a high-position stratum, the stratum is torn to generate cracks, and the cracks continuously pressurize by the fracturing fluid to enable the cracks to penetrate the stratum.
Example 1 itself can form a control test for the effect of crack formation between horizontal sections 12 of different heights and the results produced are relatively reliable as in one sample.
Example 2: in order to simulate the effect of different distances on crack formation, in an alternative embodiment, unevenly distributed perforation holes 2 are provided, the horizontal section 12 is provided with four holes 2, wherein the distance between the first hole and one end of the horizontal section 12 is 10mm, the distance between the first hole and the second hole is 15mm, the distance between the third hole and the second hole is 10mm, the distance between the fourth hole and the third hole is 5mm, and the distance between the fourth hole and the end of the horizontal section 12 is 10mm, so that unequal distances of 15mm, 10mm and 5mm are respectively constructed for judging the effect of different distances on the crack.
By combining the distribution of example 1 with example 2, the influence relationship of different jet hole 2 spacing on crack formation can be further tested.
Examples 3-4: as shown in fig. 3 and 4, in order to obtain the influence of the distribution ranges of different jet holes 2 on the crack, a plurality of jet holes 2 are divided into three clusters and arranged on the arc surface of the lower half of the horizontal segment. In this embodiment, each shower of orifices contains 3 orifices, the spacing between the orifices is 60 °, the diameter of the orifices is 5mm, the spacing between each shower of orifices is 10mm, and the spacing between the three orifices is 2mm;
the plurality of jet holes 2 are arranged on the cambered surface of the lower half part of the horizontal section 12 in three clusters, each cluster of jet holes comprises 5 holes, the distance between the holes is 30 degrees, the diameter of the holes is 3mm, and the distance between the holes is 2mm.
In examples 3 and 4, the total diameter of the jet holes 2 in the test was the same, but the distribution range of the holes per jet hole was different, and the influence relationship of the hole range on the occurrence of cracks was further examined.
Further, as shown in fig. 5 and 6, since a natural fracture exists in the rock formation, in order to simulate the influence of the natural fracture on the fracture generated in the fracturing process, one of the plurality of horizontal sections 12 is provided with a fracturing flap, including a pressure receiving plate 3 located in a simulated well bore channel and a fracture forming portion 31 extending out of the simulated well bore, the pressure receiving plate 3 and the fracture forming portion 31 are fixedly connected and rotatably connected with respect to the simulated well bore through a rotating shaft 32, so that the fracture forming portion 31 can create a crack in a fracturing sample when the fracturing fluid flows in the simulated well bore channel and is subjected to the pressure receiving plate 3.
Wherein, the seam making part 31 is penetrated out of the simulated shaft by the jet hole 2, after the sample is poured, the seam making part 31 is connected with the sample, when the pressure receiving plate 3 is stressed, the seam making part 31 can generate displacement, namely, a crack is made at the liquid outlet part of the jet hole 2 in the sample, in an alternative embodiment, the seam making part 31 can be arranged at one side of the jet hole 2, namely, the position which can be reached after the propagation of the fracturing fluid, so as to obtain the influence of natural cracks at different positions on the fracturing process through test.
As shown in connection with fig. 6, preferably the joint 32 is provided with a flat tip parallel to the radial or axial direction of the horizontal segment 12, i.e. the natural fracture created in the formation is perpendicular to the minimum horizontal stress direction and parallel to the minimum horizontal stress direction, to determine the effect of the differently directed fractures on the fracturing process.
Example 5: as shown in fig. 2 and fig. 5, three groups of tests are performed on the first horizontal stage including the fracturing flap, the second horizontal stage including the fracturing flap, or the third horizontal stage including the fracturing flap, respectively, in each group of tests, the direction of the natural fracture generation can be controlled to be different (such as perpendicular to the minimum horizontal stress direction and parallel to the minimum horizontal stress direction), and thus, the influence of the natural fracture on the fracture generation is obtained, and compared with the example 1, whether the influence of the natural fracture on the fracture formation in the fracturing process is large or the influence of the natural fracture on the fracture formation between horizontal stages 12 with different heights is large is judged.
In this embodiment, the pressure receiving plate 3 and the seam making portion 31 have an included angle in a radial plane, the pressure receiving plate 3 is inclined to the fluid inflow direction, and a limiting block 4 for limiting the overturning angle of the pressure receiving plate is arranged on the inner wall of the simulated shaft to prevent the pressure receiving plate 3 from being overturned excessively, so as to control the size of the natural seam, and of course, the size of the natural seam can also be controlled by controlling the shape of the seam making portion 31 or the size of the pressure receiving plate 3.
By combining the above embodiments, the relation between the depth of the horizontal section and the coal seam cracks, the relation between the distribution of the perforations and the intervals of the perforations on the coal seam cracks, and the relation between the existence position and the direction of the natural cracks on the coal seam cracks can be obtained, and meanwhile, the weight of the influence factors on the cracks can be obtained, so that the production direction is guided to be improved in the coal seam gas extraction process.
While the invention has been described with reference to preferred embodiments, it is not intended to be limiting. Those skilled in the art will appreciate that various modifications and adaptations can be made without departing from the spirit and scope of the present invention. Accordingly, the scope of the invention is defined by the appended claims.
Claims (9)
1. A analogue means for garrulous soft coal layer hydraulic fracturing test, characterized by, include:
a fracturing sample configured to have a coal seam roof layer, a coal seam interface layer, and a coal seam;
a simulated wellbore disposed within the roof layer of the coal seam;
the true triaxial physical simulation experiment machine is used for loading simulated three-dimensional ground stress on the fracturing sample placed in the triaxial loading chamber;
a hydraulic fracturing servo pump pressure control system for injecting fracturing fluid into the simulated wellbore to simulate a hydraulic fracturing process;
the fracturing process monitoring system is used for detecting and recording the state of a fracture of a fracturing sample in the hydraulic fracturing process;
the simulation well comprises a vertical section and at least two horizontal sections with preset intervals in the height direction, and the horizontal sections of a plurality of simulation wells are provided with the same jet holes;
one of the horizontal sections is provided with a fracturing turning plate, and the fracturing turning plate comprises a pressure receiving plate positioned in a simulated well bore channel and a seam making part extending out of the simulated well bore; the pressure receiving plate is fixedly connected with the joint making part and is rotationally connected relative to the simulated well bore, so that the joint making part can make cracks in a fracturing sample when the fracturing fluid flows in the simulated well bore channel to be subjected to the pressure receiving plate.
2. A simulation device for hydraulic fracturing testing of a crushed soft coal seam according to claim 1, wherein the height difference and the length between the horizontal sections of a plurality of simulation wells are the same, and the included angle between the connecting line of the midpoints of each horizontal section and the vertical section is 75-85 °.
3. A simulation device for hydraulic fracturing testing of a crushed soft coal seam according to claim 1, wherein the horizontal section is provided with a plurality of evenly distributed jet holes of equal size.
4. A simulation device for hydraulic fracturing testing of a crushed soft coal seam according to claim 3, wherein a plurality of jet holes are arranged right below the horizontal section in a straight arrangement and are unevenly distributed.
5. A simulation apparatus for hydraulic fracturing testing of a crushed soft coal seam according to claim 3, wherein a plurality of the jet holes are divided into clusters and are arranged on the cambered surface of the lower half of the horizontal section.
6. A simulation apparatus for hydraulic fracturing testing of a crushed soft coal seam according to claim 5, wherein each cluster of jet holes comprises 3 holes with a 60 ° spacing between holes or 5 holes with a 30 ° spacing between holes.
7. A simulation device for hydraulic fracturing testing of a crushed soft coal seam according to claim 1, wherein the seam making part is penetrated out of the simulated wellbore by the jet hole.
8. A simulation device for hydraulic fracturing tests of a crushed soft coal seam according to claim 1, characterized in that the seam making part is provided with flat tips parallel to the radial or axial direction of the horizontal section.
9. The simulation device for hydraulic fracturing test of the crushed soft coal layer according to claim 1, wherein the pressure receiving plate and the joint making part form an included angle in a radial plane, the pressure receiving plate is inclined to the inflow direction of fluid, and a limiting block for limiting the overturning angle of the pressure receiving plate is arranged on the inner wall of the simulated shaft.
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| CN113653470B (en) * | 2021-10-21 | 2022-04-29 | 西南石油大学 | Coal bed in-situ hydrogen production and coal bed gas development integrated method and structure |
| CN114922591A (en) * | 2022-06-06 | 2022-08-19 | 中煤科工集团西安研究院有限公司 | Directional cross-layer fracturing simulation test method for horizontal well of soft coal seam roof rock stratum |
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| CN104060976B (en) * | 2014-07-01 | 2017-02-15 | 中国石油大学(北京) | Method for physically simulating sectional hydrofracture of different well types of perforated well shafts |
| CN105181927B (en) * | 2015-08-05 | 2017-11-28 | 河南能源化工集团研究院有限公司 | The hypotonic coal seam hydraulic fracture simulation experiment method of multi- scenarios method |
| CN206990290U (en) * | 2017-05-08 | 2018-02-09 | 西南石油大学 | A kind of rock core man stitches device |
| CN107387034B (en) * | 2017-08-30 | 2020-06-09 | 中煤科工集团西安研究院有限公司 | Extraction method of horizontal coal bed gas well completed by non-well-cementing casing |
| CN207377560U (en) * | 2017-09-06 | 2018-05-18 | 河南省生产力促进中心 | A kind of orientation hydraulic fracturing overhead caving device |
| CN209199463U (en) * | 2018-10-24 | 2019-08-02 | 盘锦中录油气技术服务有限公司 | A kind of experimental provision for simulating unconventional oil and gas reservoir micro-fractures |
| CN111980645B (en) * | 2019-05-23 | 2022-11-04 | 中国石油天然气股份有限公司 | Seam making device, and system and process for simulating sand filling model displacement experiment process |
| CN210858687U (en) * | 2019-11-14 | 2020-06-26 | 于孝民 | Oil well hydraulic stratum seam-making device |
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