CN113622891B - Dredging type fracturing method of high-rank coal reservoir - Google Patents
Dredging type fracturing method of high-rank coal reservoir Download PDFInfo
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- 239000003245 coal Substances 0.000 title claims abstract description 287
- 238000000034 method Methods 0.000 title claims abstract description 40
- 239000012530 fluid Substances 0.000 claims abstract description 196
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 65
- 239000007788 liquid Substances 0.000 claims abstract description 22
- 238000006073 displacement reaction Methods 0.000 claims abstract description 11
- 239000004576 sand Substances 0.000 claims description 74
- WCUXLLCKKVVCTQ-UHFFFAOYSA-M Potassium chloride Chemical compound [Cl-].[K+] WCUXLLCKKVVCTQ-UHFFFAOYSA-M 0.000 claims description 32
- 239000004927 clay Substances 0.000 claims description 21
- 239000003381 stabilizer Substances 0.000 claims description 20
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 18
- 239000001103 potassium chloride Substances 0.000 claims description 16
- 235000011164 potassium chloride Nutrition 0.000 claims description 16
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 72
- 238000005086 pumping Methods 0.000 description 33
- 239000002245 particle Substances 0.000 description 30
- 239000006004 Quartz sand Substances 0.000 description 10
- 230000008569 process Effects 0.000 description 10
- 230000000694 effects Effects 0.000 description 8
- 238000010276 construction Methods 0.000 description 7
- 230000009466 transformation Effects 0.000 description 6
- 230000035699 permeability Effects 0.000 description 5
- 230000015572 biosynthetic process Effects 0.000 description 4
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 4
- 239000011435 rock Substances 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 238000001914 filtration Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
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- 239000000243 solution Substances 0.000 description 2
- 125000003277 amino group Chemical group 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000002817 coal dust Substances 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- UXYBXUYUKHUNOM-UHFFFAOYSA-M ethyl(trimethyl)azanium;chloride Chemical compound [Cl-].CC[N+](C)(C)C UXYBXUYUKHUNOM-UHFFFAOYSA-M 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000002093 peripheral effect Effects 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
- 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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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
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- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/60—Compositions for stimulating production by acting on the underground formation
- C09K8/80—Compositions for reinforcing fractures, e.g. compositions of proppants used to keep the fractures open
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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
- E21B43/267—Methods for stimulating production by forming crevices or fractures reinforcing fractures by propping
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- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
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- Y02A90/30—Assessment of water resources
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Abstract
The present disclosure provides a method of dredging fracturing a high-rank coal reservoir, comprising: determining the depth range of raw coal in the high-rank coal reservoir according to the logging data; perforating in a shaft corresponding to the middle area of the depth range of the primary coal of the high-order coal reservoir, and forming a plurality of holes in the inner wall of the shaft; injecting a first fracturing fluid through a plurality of holes to form a first fracture in raw coal of a high-rank coal reservoir; injecting a second fracturing fluid into the raw coal of the high-rank coal reservoir through a plurality of holes to form a second crack, wherein the first crack is communicated with the second crack, and the second fracturing fluid is a mixed fluid of the first fracturing fluid and a crack propping agent; injecting displacement fluid from the well bore, displacing the first fracturing fluid and the second fracturing fluid in raw coal of the high-order coal reservoir; stopping injecting liquid into the shaft, and directly returning the liquid without being closed to the well. The method can carry out fracturing reformation on the raw coal in the high-rank coal reservoir, and improves the gas yield of the gas well.
Description
Technical Field
The disclosure relates to the technical field of coalbed methane exploitation, in particular to a dredging type fracturing method of a high-rank coal reservoir.
Background
Hydraulic fracturing technology is an important means for the reformation of high-rank coal reservoirs. Hydraulic fracturing utilizes the pressure transmission performance of fracturing fluid, pumps the fracturing fluid into a well based on a ground high-pressure pump set, and when the bottom hole pressure is greater than the ground stress near the well wall and the tensile strength of reservoir rock, the stratum is cracked to generate cracks. Then pumping sand-carrying fluid containing sand propping agent into the crack to fill the crack and extend the crack, forming sand-filled crack with high flow conductivity at the bottom of the well, increasing permeability and achieving the purpose of increasing yield.
Due to the influence of stress in the formation process of the high-rank coal reservoir, the high-rank coal reservoir can be crushed to different degrees, and different types of coal structures can be formed in the reservoir. The coal body structure of the high-rank coal reservoir comprises raw coal and structural coal. Wherein, the raw coal is hard coal, the strength is higher, and the cementing property of the structural coal is poor, the strength is low, and the structural coal is easy to crush.
During hydraulic fracturing, the fracturing fluid breaks through the structural coal with weak strength first, and a high-diversion seepage zone is formed at the position of the structural coal. And the pressure in the shaft can not reach the burst pressure intensity of the raw coal, so the raw coal can not realize reservoir reformation. Because the gas content of the constructed coal is low, the gas well has less gas yield after hydraulic fracturing.
Disclosure of Invention
The embodiment of the disclosure provides a dredging type fracturing method of a high-rank coal reservoir, which can carry out fracturing transformation on raw coal in the high-rank coal reservoir and improve the gas yield of a gas well. The technical scheme is as follows:
the embodiment of the disclosure provides a dredging type fracturing method of a high-rank coal reservoir, which comprises the following steps: determining the depth range of raw coal in a high-order coal reservoir according to logging data; perforating in a shaft corresponding to the middle area of the depth range of the primary coal of the high-order coal reservoir, and forming a plurality of holes in the inner wall of the shaft; injecting a first fracturing fluid through the plurality of perforations to form a first fracture in raw coal of the high-order coal reservoir; injecting a second fracturing fluid into raw coal of the high-order coal reservoir through the plurality of holes to form a second crack, wherein the first crack is communicated with the second crack, and the second fracturing fluid is a mixed fluid of the first fracturing fluid and a crack propping agent; injecting a displacement fluid from within the wellbore, displacing the first fracturing fluid and the second fracturing fluid in the primary coal of the high-order coal reservoir; stopping injecting liquid into the shaft, and directly returning the liquid without being closed to the well.
In one implementation of the embodiment of the disclosure, the determining, according to the logging data, a depth range of raw coal in a high-rank coal reservoir, includes: acquiring the logging data of different areas in the high-order coal reservoir, wherein the logging data comprises: at least one of resistivity of the high-rank coal reservoir, acoustic time difference of the high-rank coal reservoir, natural gamma value of the high-rank coal reservoir, and density log of the high-rank coal reservoir; determining a depth range of raw coal in the high-order coal reservoir from the logging data.
In another implementation of an embodiment of the present disclosure, the determining a depth range of raw coal in the higher order coal reservoir from the logging data includes: if the logging data meets the area of the first determined relation, determining the depth range of all areas meeting the first determined relation in the high-order coal reservoir as the depth range of the raw coal in the high-order coal reservoir, wherein the first determined relation comprises at least one of the following: the resistivity is greater than 3000 Ω -m, the acoustic time difference is between 370 and 410 μs/m, the natural gamma value is between 30 and 80API, and the density logging is 1.3g/cm 3 To 1.6g/cm 3 Between them.
In another implementation of an embodiment of the present disclosure, the perforating at a middle region of a depth range of raw coal corresponding to the higher-order coal reservoir within a wellbore includes: and carrying out concentrated perforation in the middle area of the depth range of the primary coal of the high-order coal reservoir in the well bore, wherein the perforation density is 10 holes/m to 20 holes/m, the perforation depth is 2.5m to 3.0m, and the perforation direction is perpendicular to the minimum main stress direction of the coal bed.
In another implementation of the embodiments of the present disclosure, the injecting a second fracturing fluid through the plurality of perforations, before forming a second fracture in raw coal of the high-order coal reservoir, the diverting fracturing method further includes: injecting a third fracturing fluid from the plurality of holes, so that a crack propping agent in the third fracturing fluid supports the first crack, wherein the third fracturing fluid is a mixed liquid of the first fracturing fluid and the crack propping agent, and the content of the crack propping agent of the third fracturing fluid is lower than that of the second fracturing fluid; the injecting a second fracturing fluid through the plurality of perforations to form a second fracture in raw coal of the high-order coal reservoir, comprising: injecting the second fracturing fluid from the plurality of perforations, causing the second fracturing fluid to form the second fracture in raw coal of the high-order coal reservoir and causing fracture proppants within the second fracturing fluid to prop the second fracture.
In another implementation of an embodiment of the present disclosure, the injecting the second fracturing fluid from the plurality of perforations includes: the second fracturing fluid is injected from the plurality of perforations into the first fracture in a manner that progressively increases the rate of injection of the second fracturing fluid and the mass percent of fracture proppant in the second fracturing fluid.
In another implementation of an embodiment of the present disclosure, the injecting the second fracturing fluid from the plurality of perforations into the first fracture in a manner that progressively increases a rate of injection of the second fracturing fluid and a mass percent of fracture proppant in the second fracturing fluid includes: and sequentially and continuously injecting the second fracturing fluid into the first fracture according to a first speed, a second speed and a third speed, wherein the first speed is smaller than the second speed, the second speed is smaller than the third speed, the mass percent of the fracture propping agent of the second fracturing fluid is a first content when the second fracturing fluid is injected according to the first speed, the mass percent of the fracture propping agent of the second fracturing fluid is a second content when the second fracturing fluid is injected according to the second speed, and the mass percent of the fracture propping agent of the second fracturing fluid is a third content when the second fracturing fluid is injected according to the third speed, and the first content is smaller than the second content and the second content is smaller than the third content.
In another implementation of an embodiment of the present disclosure, the three fracturing fluids include: the crack propping agent comprises, by mass, 1.0 to 2.0% of potassium chloride, 0.2 to 0.5% of clay stabilizer, 6.0 to 8.0% of crack propping agent and the balance of water; the second fracturing fluid comprises: the crack propping agent comprises, by mass, 1.0 to 2.0% of potassium chloride, 0.2 to 0.5% of clay stabilizer, 12 to 20% of crack propping agent and the balance of water.
In another implementation manner of the embodiment of the present disclosure, the crack propping agent is a sand propping agent, the sand propping agent of the second fracturing fluid includes three kinds of support sand with different particle sizes, wherein the mass percentage of the support sand with the smallest particle size is 16.7%, the mass percentage of the support sand with the largest particle size is 33.3%, the mass percentage of the support sand with the particle size between the support sand with the smallest particle size and the support sand with the largest particle size is 50.0%, and the particle size of the sand propping agent of the third fracturing fluid is the support sand with the particle size between the support sand with the smallest particle size and the support sand with the largest particle size in the sand propping agent of the second fracturing fluid.
In another implementation of an embodiment of the present disclosure, the first fracturing fluid includes: the clay stabilizer comprises, by mass, 1.0 to 2.0% of potassium chloride, 0.2 to 0.5% of clay stabilizer and the balance of water.
In another implementation manner of the embodiment of the present disclosure, the dredging type fracturing method further includes: measuring wellhead pressure, and determining flowback parameters according to the wellhead pressure; the determining flowback parameters according to the wellhead pressure comprises: if the wellhead pressure is greater than 20Mpa, a choke with the diameter of 6mm is adopted for flowback; if the wellhead pressure is 10Mpa to 20Mpa, a choke with the diameter of 10mm is adopted for flowback; if the wellhead pressure is 5Mpa to 10Mpa, a choke with the diameter of 12mm is adopted for flowback; and if the wellhead pressure is less than 5MPa, adopting a 14mm oil nozzle to perform flowback.
The technical scheme provided by the embodiment of the disclosure has the beneficial effects that at least:
the dredging type fracturing method of the high-rank coal reservoir comprises the steps of firstly judging the structural development characteristics of coal bodies of the high-rank coal reservoir based on logging data, locking the development layer segments of raw coal in the high-rank coal reservoir, and determining the position of the raw coal in the high-rank coal reservoir; then, perforating is carried out in the middle area of the depth range of the primary coal corresponding to the high-order coal reservoir in the well shaft, and a plurality of holes are formed in the inner wall of the well shaft. After forming holes in the shaft, injecting a first fracturing fluid from a plurality of holes into the high-order coal reservoir, so that a first crack is formed at the raw coal in the high-order coal reservoir, the seepage resistance of the reservoir is primarily reduced, and yield increase is realized. And simultaneously, injecting a second fracturing fluid from a plurality of holes into the first fracture to further expand the trend and depth of the first fracture in the reservoir, so that a second fracture is formed deeper into the reservoir on the basis of the first fracture in the reservoir, and a long fracture is formed in the high-rank coal reservoir. And propping the long seam by means of a crack propping agent in the second fracturing fluid. Under the action of the second fracturing fluid, the main seam in the reservoir extends out of a plurality of sub-seams along different lateral directions of the main seam to form a netlike seam system, so that the seam making effect is improved, and the seepage resistance of the reservoir is reduced. Then, injecting displacement liquid from the shaft, displacing the first fracturing liquid and the second fracturing liquid in the raw coal of the high-order coal reservoir, and ensuring that the first fracturing liquid and the second fracturing liquid can completely support the first fracture and the second fracture, so that the netlike fracture system can be more stable. Finally, after the displacement fluid is pumped, the non-tight well is adopted to directly carry out flowback, so that the reservoir pressure can be quickly reduced to the original stratum pressure, the filtration of the fracturing fluid and the degree of polluting the reservoir are reduced, the high-pressure fluid and the pulverized coal are guided to be quickly discharged, cracks are kept clean, and the lifting of the reservoir pressure and the expansion range of the fracturing fluid to the periphery are more effectively relieved.
According to the embodiment of the disclosure, the depth range of the raw coal in the high-rank coal reservoir is determined through logging data, and then perforation is carried out in the shaft corresponding to the depth of the raw coal, so that the situation that the fracturing fluid easily forms a high-diversion seepage zone at the position of the structural coal when the related technology is used for fracturing is avoided. The reformation of raw coal in a high-rank coal reservoir is realized, and the gas yield of a gas well can be improved; simultaneously, through respectively injecting first fracturing fluid and second fracturing fluid into and forming netted crack system, improved the seam effect of making, realized increasing production.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present disclosure, and other drawings may be obtained according to these drawings without inventive effort for a person of ordinary skill in the art.
FIG. 1 is a flow chart of a method of conducting fracturing of a high rank coal reservoir provided by embodiments of the present disclosure;
fig. 2 is a flow chart of another method of conducting fracturing of a high rank coal reservoir provided by embodiments of the present disclosure.
Detailed Description
For the purposes of clarity, technical solutions and advantages of the present disclosure, the following further details the embodiments of the present disclosure with reference to the accompanying drawings.
Fig. 1 is a flow chart of a method of conducting fracturing of a high rank coal reservoir provided by an embodiment of the present disclosure. As shown in fig. 1, the fracturing method includes:
s101: and determining the depth range of raw coal in the high-rank coal reservoir according to the logging data.
S102: perforating in the shaft corresponding to the middle area of the depth range of the primary coal of the high-order coal reservoir, and forming a plurality of holes in the inner wall of the shaft.
S103: a first fracturing fluid is injected through the plurality of perforations to form a first fracture in raw coal of the high rank coal reservoir.
S104: and injecting a second fracturing fluid through the plurality of holes to form second cracks in raw coal of the high-rank coal reservoir.
The first fracture is communicated with the second fracture, and the second fracturing fluid is a mixed fluid of the first fracturing fluid and a fracture propping agent.
S105: and injecting displacement fluid from the well bore, and displacing the first fracturing fluid and the second fracturing fluid in raw coal of the high-order coal reservoir.
S106: stopping injecting liquid into the shaft, and directly returning the liquid without being closed to the well.
The dredging type fracturing method of the high-rank coal reservoir comprises the steps of firstly determining the depth position of raw coal in the high-rank coal reservoir according to logging data, namely judging the structural development characteristics of coal bodies of the high-rank coal reservoir based on the logging data, locking the development layer segments of the raw coal in the high-rank coal reservoir, and determining the position of the raw coal in the high-rank coal reservoir; then, perforating the middle area of the depth range of the primary coal corresponding to the high-order coal reservoir in the well bore, and forming a plurality of holes on the inner wall of the well bore, namely forming dense holes. Because the boundary area of the depth range of the raw coal is mostly the construction coal with weak strength, if the perforation position completely corresponds to the position of the whole raw coal, the fracturing fluid can enter the construction coal, and a high-diversion seepage zone is formed at the position of the construction coal, so that the hydraulic fracturing transformation of the raw coal is not facilitated, and therefore, the perforation is carried out in the middle area of the depth range of the raw coal of the high-rank coal reservoir, the situation that the fracturing fluid enters the construction coal in the hydraulic fracturing process can be effectively avoided, and the reservoir transformation effect is ensured. After dense holes are formed in a shaft, a first fracturing fluid is injected into a high-order coal reservoir from a plurality of holes, when the first fracturing fluid is pumped down at the bottom of the shaft, and the pressure is higher than the strength of raw coal in the high-order coal reservoir where the holes are positioned, the raw coal in the high-order coal reservoir generates cracks (namely, first cracks), and the first cracks formed at the raw coal in the high-order coal reservoir are formed, so that the seepage resistance of the reservoir is primarily reduced, the permeability is increased, and the yield is increased. Meanwhile, a second fracturing fluid is injected into the first fracture from a plurality of holes, the trend and the depth of the first fracture in the reservoir are further expanded by the second fracturing fluid, so that a second fracture is formed in the reservoir to a deeper part of the reservoir on the basis of the first fracture in the reservoir, the second fracture is communicated with the first fracture, a long fracture is formed in a high-rank coal reservoir, meanwhile, the long fracture is supported by a fracture propping agent in the second fracturing fluid, so that the long fracture is firmer, under the action of the second fracturing fluid, the fracture in the reservoir can continue to extend into the reservoir, and a plurality of sub-fractures extend from different sides of the main fracture on the basis of taking the first fracture and the second fracture as main fractures, so that a plurality of dendritic fractures are formed, namely the main fracture and the sub-fractures are mutually intersected, a netlike fracture system is jointly formed, the joint making effect is improved, and the netlike fracture system formed in the raw coal in the high-rank coal reservoir can further reduce the seepage resistance of the reservoir, so that the permeability is increased, and the yield is increased. And then, injecting displacement liquid from the shaft, displacing the first fracturing liquid and the second fracturing liquid in the raw coal of the high-order coal reservoir, and ensuring that the first fracturing liquid and the second fracturing liquid can completely support the first cracks and the second cracks, so that a netlike crack system formed at the raw coal of the high-order coal reservoir can be more stable and reliable. Finally, in the embodiment of the disclosure, after the displacement fluid is pumped, the flowback is directly carried out by adopting the non-tight well, so that the reservoir pressure can be quickly reduced to the original stratum pressure, the filtration of the fracturing fluid and the degree of polluting the reservoir are reduced, the high-pressure fluid and the pulverized coal are guided to be quickly discharged, the cracks are kept clean, and the lifting of the reservoir pressure and the expansion range of the fracturing fluid to the peripheral erosion are more effectively relieved. Therefore, compared with the construction process of re-drainage after well-closing after hydraulic fracturing in the related art, the dredging type fracturing method provided by the embodiment of the disclosure can control the lifting of reservoir pressure, reduce the filtration loss of fracturing fluid and the degree of pollution to the reservoir, and can effectively improve the yield of the coalbed methane reservoir. When the fracturing is carried out, the depth position of the raw coal in the high-rank coal reservoir is determined through logging data, and then perforation is carried out in the shaft corresponding to the depth position of the raw coal, so that the situation that the fracturing fluid easily breaks through the structural coal with weak strength and a high-diversion seepage zone is formed at the structural coal position in the fracturing of the related technology is avoided, the transformation of the raw coal in the high-rank coal reservoir is realized, and the gas yield of a gas well can be improved due to the high gas content of the raw coal; meanwhile, a net-shaped crack system taking the first crack and the second crack as main cracks is formed by respectively injecting the first fracturing fluid and the second fracturing fluid, so that the crack making effect is improved, the seepage resistance of the area where raw coal is located in the high-rank coal reservoir is reduced, the permeability is increased, and the yield is increased.
Fig. 2 is a flow chart of another method of conducting fracturing of a high rank coal reservoir provided by embodiments of the present disclosure. As shown in fig. 2, the fracturing method includes:
s201: and determining the depth range of raw coal in the high-order coal reservoir according to the logging data.
The logging data may be measured by productivity logging before the use of the gas well, and the productivity logging may measure various data.
Since the coal body structure of the high-rank coal reservoir includes raw coal and structural coal, the structural coal includes crushed coal, and crushed coal. And the response relations between different types of coal structures and four types of logging data are different, so that the coal structure of the high-order coal reservoir can be judged according to the combination of the four types of logging data, namely resistivity, acoustic time difference, natural gamma value and density logging.
The logging data used in S201 to identify and determine the location of the distribution of the coal body structure in the higher rank coal reservoir may include: at least one of resistivity of the high-rank coal reservoir, sonic time difference of the high-rank coal reservoir, natural gamma value of the high-rank coal reservoir, and density log of the high-rank coal reservoir.
The coal body structure of the high rank coal reservoir in the embodiments of the present disclosure may be determined according to the following data table:
when determining the position of raw coal in a high-rank coal reservoir according to logging data, logging data of different areas in the high-rank coal reservoir are firstly obtained, and the depth position of the raw coal in the high-rank coal reservoir is determined according to the logging data. Is combined withAnd if the areas meeting the first determined relation exist in the high-order coal reservoir, determining the depth range of all the areas meeting the first determined relation in the high-order coal reservoir as the depth position of the raw coal in the high-order coal reservoir. Wherein the first determined relationship may include at least one of: the resistivity is larger than 3000 Ω & m, the acoustic time difference is between 370 and 410 mu s/m, the natural gamma value is between 30 and 80API, and the density logging is between 1.3 and 1.6g/cm 3. If the areas meeting the second determined relation exist in the high-order coal reservoir, determining the depth range of all the areas meeting the second determined relation in the high-order coal reservoir as the depth position of the broken coal in the high-order coal reservoir. Wherein the second determining relationship comprises: the resistivity is between 1000 omega-3000 omega-m, the acoustic wave time difference is more than 380 mu s/m, the natural gamma value is less than 60API, and the density logging is 1.2g/cm 3 To 1.35g/cm 3 Between them. If the areas meeting the third determined relation exist in the high-order coal reservoir, determining the depth range of all the areas meeting the third determined relation in the high-order coal reservoir as the depth position of the crushed coal or the minced coal in the high-order coal reservoir. Wherein the third determining relationship comprises: resistivity greater than 1000Ω.m, sonic time difference greater than 410 μs/m, natural gamma value less than 60API, density logging at 1.1g/cm 3 To 1.25g/cm 3 Between them.
S202: perforating in the shaft corresponding to the middle area of the depth range of the primary coal of the high-order coal reservoir, and forming a plurality of holes in the inner wall of the shaft.
S202 may include: centralized perforation is performed at the location of the raw coal of the higher rank coal reservoir in the wellbore. Wherein, the perforation density is 16 holes/m, and the perforation depth is 2.5m to 3.0 m. The centralized perforation is used for enabling the pressure of water conservancy fracturing to be more centralized in the fracturing process, and facilitating long seam making. In embodiments of the present disclosure, the perforation direction may be selected to be perpendicular to the direction of minimal principal stress of the coal seam. The perforation direction is set to be perpendicular to the minimum main stress direction of the coal seam, so that the resistance is relatively small in the process of expanding the fracturing fracture, and the purpose of making a long seam is achieved.
S203: and injecting a first fracturing fluid into the high-order coal reservoir through the plurality of holes to form a first crack in raw coal of the high-order coal reservoir.
S203 may include: and pumping the first fracturing fluid into the region where the raw coal is located in the high-order coal reservoir through a plurality of holes. The first fracturing fluid can be a pre-fluid, the fracturing construction is started on the coal seam position where perforation is completed, and when the pressure of the first fracturing fluid at the bottom hole is greater than the strength of raw coal in the high-order coal reservoirs at the positions of the plurality of holes, the first fracturing fluid generates first cracks in the raw coal areas in the high-order coal reservoirs. The first fracturing fluid is an active water fracturing fluid and can comprise 1.0 to 2.0 mass percent of potassium chloride, 0.2 to 0.5 mass percent of clay stabilizer and the balance of water. The active water fracturing fluid of the components is low in cost, and can effectively solve the problem of expansion of coal rock and clastic rock clay, and further reduce the damage to a reservoir in the fracturing process. The clay stabilizer may be 2-ethyl trimethyl ammonium chloride, quaternary amine clay stabilizer, etc. and the embodiment of the present disclosure is not limited.
In S203, the pumping speed of the first fracturing fluid may be 4.0m 3 /min to 5.0m 3 The pumping quantity per minute can be 70m 3 To 100m 3 . Illustratively, the pumping speed of the first fracturing fluid may be 4.0m 3 /min to 4.5m 3 The pumping quantity per minute can be 90m 3 . The pumping speed and pumping quantity of the first fracturing fluid can be controllably used for making a seam at the position of the primary coal in the high-rank coal reservoir, and the pumping speed and pumping quantity of the first fracturing fluid can be further expanded to enter other positions in the high-rank coal reservoir, such as a weak surface for constructing coal positions and combining other rocks.
S204: and injecting a third fracturing fluid into the first fracture through the plurality of holes, so that fracture proppants in the third fracturing fluid support the first fracture.
The third fracturing fluid is a mixed fluid of the first fracturing fluid and a crack propping agent, and the content of the crack propping agent of the third fracturing fluid is lower than that of the second fracturing fluid. Illustratively, the third fracturing fluid may comprise: potassium chloride, clay stabilizer, fracture propping agent and water. 1.0 to 2.0 percent of potassium chloride, 0.2 to 0.5 percent of clay stabilizer, 6.0 to 8.0 percent of crack propping agent and the balance of water.
The pumping speed of the third fracturing fluid in S204 is 2.5m 3 /min to 4.5m 3 The pumping quantity per minute can be 150m 3 To 200m 3 The dosage of the fracture propping agent can be 5m 3 To 15m 3 . Illustratively, the pumping speed of the third fracturing fluid may be 3.0m 3 /min to 4.0m 3 Per min, the pumping quantity is 180m 3 The dosage of the fracture propping agent can be 10m 3 . The pumping speed and the pumping quantity of the third fracturing fluid can further expand the trend and the depth of the first fracture in the coal seam, so that the third fracturing fluid penetrates into the coal seam, and long seams are formed in the coal seam. The crack propping agent can be a sand propping agent, and the sand propping agent in the third fracturing fluid can be natural quartz sand with the particle size of 20-40 meshes. Thus, the first crack is filled and supported by the natural quartz sand in the third fracturing fluid, so that the first crack is more stable and reliable.
S205: and injecting a second fracturing fluid into the first fracture through the plurality of holes, so that the second fracturing fluid forms a second fracture in the raw coal of the high-rank coal reservoir and a fracture propping agent in the second fracturing fluid supports the second fracture.
Wherein the second fracturing fluid may comprise: potassium chloride, clay stabilizer, fracture propping agent and water. 1.0 to 2.0 percent of potassium chloride, 0.2 to 0.5 percent of clay stabilizer, 12 to 20 percent of sand propping agent and the balance of water. That is, in embodiments of the present disclosure, the third fracturing fluid and the second fracturing fluid each include a fracture proppant, and the third fracturing fluid has a lower level of fracture proppant than the second fracturing fluid.
In S205, the second fracturing fluid pump may have a filling rate of 200m 3 To 250m 3 . For example, the second frac fluid pump may be 220m in volume 3 . The second fracturing fluid based on the pumping quantity not only can support fracturing and seam making, but also can ensure that the formed cracks are filled with the crack propping agent, and the seam making effect is effectively improved.
And S205, pumping a second fracturing fluid into the reservoir through a plurality of holes continuously to form a second crack communicated with the first crack in the primary layer of the high-rank coal reservoir, so that the crack can continuously extend into the high-rank coal reservoir and form a plurality of dendritic cracks filled with crack propping agents in the high-rank coal reservoir. The branch cracks are a plurality of sub cracks which take the first cracks and the second cracks as main cracks and extend along different directions, the main cracks and the sub cracks can be mutually intersected to form a netlike crack system, the crack making effect is improved, the seepage resistance of the area where raw coal is located in the high-rank coal reservoir is reduced, the permeability is increased, and the yield is increased.
Alternatively, the fracture proppants in the second fracturing fluid may be sand proppants, which may include: the three kinds of support sand with different particle sizes, wherein the mass percentage of the support sand with the smallest particle size is 16.7%, the mass percentage of the support sand with the largest particle size is 33.3%, and the mass percentage of the support sand with the particle size between the support sand with the smallest particle size and the support sand with the largest particle size is 50.0%. Illustratively, the sand proppant in the second fracturing fluid may be a multi-particle size sand proppant combination comprising coarse, medium, and fine particle size natural quartz sand. That is, the multi-grain size sand proppant combination comprises a support sand with the smallest grain size, a support sand with the grain size between the support sand with the smallest grain size and the support sand with the largest grain size, and a support sand with the largest grain size. And according to the mass percentage, the supporting sand with the smallest grain diameter, the supporting sand with the grain diameter between the supporting sand with the smallest grain diameter and the supporting sand with the largest grain diameter are 16.7 percent: 50.0%:33.3%. The particle size of the support sand with the smallest particle size is 12-20 meshes, the particle size of the support sand between the support sand with the smallest particle size and the support sand with the largest particle size is 20-40 meshes, and the particle size of the support sand with the largest particle size is 40-70 meshes. And the usage amount of the sand propping agent in the second fracturing fluid can be 25m 3 Up to 35m 3 。
The supporting sand in the implementation mode can be natural quartz sand, so that the second cracks and the plurality of dendritic cracks are filled and supported by the aid of the natural quartz sand in the second fracturing fluid, and the second cracks and the formed netlike crack system are firmer and more reliable. According to the embodiment of the disclosure, the second fracturing fluid combined with the sand propping agent with multiple particle sizes is adopted for carrying out a hydraulic fracturing modification process, so that the sand propping agent can be filled into multiple cracks formed in a high-rank coal reservoir, and a network crack system extending in a long distance is formed in the high-rank coal reservoir, so that cracks at all levels are effectively supported, and the smoothness of the fracturing cracks is kept.
In S205, injecting the second fracturing fluid through the plurality of perforations may include: and sequentially injecting a second fracturing fluid into the first fracture according to a first speed, a second speed and a third speed, wherein the first speed is smaller than the second speed, the second speed is smaller than the third speed, the mass percent of the sand propping agent of the second fracturing fluid is the first content when the second fracturing fluid is injected according to the first speed, the mass percent of the sand propping agent of the second fracturing fluid is the second content when the second fracturing fluid is injected according to the second speed, the mass percent of the sand propping agent of the second fracturing fluid is the third content when the second fracturing fluid is injected according to the third speed, the first content is smaller than the second content, and the second content is smaller than the third content. Exemplary, the first speed is 3.0m 3 /min to 4.5m 3 /min, second speed of 5.0m 3 /min to 6.5m 3 /min, third speed of 7.0m 3 /min to 8.5m 3 And/min, wherein the first content is 12-14%, the second content is 15-17%, and the third content is 18-20%. In the embodiment of the disclosure, the second fracturing fluid is pumped by adopting a variable speed method for gradually increasing the pumping speed, and the pumping process is as follows: controlling the pumping speed of the second fracturing fluid to be 3.0m in sequence 3 /min to 4.5m 3 /min，5.0m 3 /min to 6.5m 3 /min，7.0m 3 /min to 8.5m 3 Per min, and the pumping speed is 4.0m in sequence 3 /min，5.5m 3 /min，7.5m 3 And/min. Accordingly, the mass percent of the sand proppants in the second fracturing fluid is controlled to be 12 to 14%,15 to 17%,18 to 20%, for example, 13%, 16%, 18% of the mass percent of the sand proppants in the second fracturing fluid. Embodiments of the present disclosure pass through stairsThe second fracturing fluid is pumped in a mode of improving the pumping speed, so that the extending distance of the main seam is ensured, the pumping speed of the sand-carrying fluid and the content of sand propping agents are gradually improved, the extending range of branch seams near the main seam is further expanded, the fracturing transformation range is improved, and a long-distance supporting seam net is formed in the coal seam.
S206: and injecting displacement fluid from the well bore, and displacing the first fracturing fluid and the second fracturing fluid in raw coal of the high-order coal reservoir.
In S206, the displacement fluid may include 1.0 to 2.0% by mass of potassium chloride, 0.2 to 0.5% by mass of clay stabilizer, and water in balance. The third fracturing fluid and the second fracturing fluid remaining in the wellbore can be displaced into the Gao Jiemei reservoir by the displacement fluid.
S207: stopping injecting liquid into the shaft, and directly returning the liquid without being closed to the well.
In S207, wellhead pressure can be measured during flowback, and flowback parameters can be determined according to the wellhead pressure. In order to achieve complete and thorough flowback in the embodiment of the disclosure, the flowback process can be performed in the following manner: if the wellhead pressure is greater than 20Mpa, a choke with the diameter of 6mm is adopted for flowback; if the wellhead pressure is 10Mpa to 20Mpa, a choke with the diameter of 10mm is adopted for flowback; if the wellhead pressure is 5Mpa to 10Mpa, a choke with the diameter of 12mm is adopted for flowback; and if the wellhead pressure is less than 5MPa, adopting a 14mm oil nozzle to perform flowback. According to the embodiment of the disclosure, the well is not closed after fracturing, the flowback is fast, the formation pressure is fast reduced to the original formation pressure, the fracturing fluid loss and the reservoir pollution degree are reduced, the high-pressure liquid and the coal dust are guided to be fast discharged, the cracks are kept clean, and the lifting of the formation pressure and the expansion range of the fracturing fluid to the periphery are effectively relieved.
Taking a Zheng Zhuang-block high-rank coal reservoir in the south of the Qin region of Shanxi as an example, the depth of the high-rank coal reservoir ranges from 703.65 meters to 709.65 meters, the thickness of the high-rank coal reservoir is 6 meters, the top and bottom plates of the high-rank coal reservoir are mudstones and sandy mudstones, the middle part of the high-rank coal reservoir is developed into raw coal, and broken coal and a small amount of broken coal are arranged on two sides of the high-rank coal reservoir.
First, logging is utilizedAnd (3) establishing a coal body structure identification model according to response characteristics between the data and different types of coal body structures, determining that raw coal of the high-rank coal reservoir is distributed in a depth range of 704.85 meters to 708.35 meters according to logging data, wherein the thickness of the raw coal is 3.50 meters, the top of the high-rank coal reservoir is mostly broken coal, and the bottom of the high-rank coal reservoir is broken coal and a small amount of broken coal. Then, perforating is carried out in the middle area of the depth range of the primary coal corresponding to the high-order coal reservoir in the well shaft, and a plurality of holes are formed in the inner wall of the well shaft. And the perforation density is controlled to be 16 holes/meter, the perforation thickness is 3 meters, the perforation depth is 705.0 meters to 708.0 meters (namely the middle area of the depth range), and the number of perforations is 48. Then pumping a first fracturing fluid which comprises 1.0 percent of KCl, 0.2 percent of clay stabilizer and the balance of water by mass percent, and controlling the pumping speed of the first fracturing fluid to be 4.5m 3 /min, 90m into Gao Jiemei reservoir via multiple perforations 3 And (3) carrying out fracturing construction on the first fracturing fluid to form a first crack in the high-rank coal reservoir. Then pumping a third fracturing fluid which comprises 1.0% of KCl, 0.2% of clay stabilizer, 8.0% of natural quartz sand and the balance of water by mass. Controlling the pumping speed of the third fracturing fluid to be 3.5m 3 Pumping 180m into the first crack 3 Is a third fracturing fluid. The sand propping agent in the third fracturing fluid is Lanzhou quartz sand with the particle size of 20-40 meshes and the dosage of 10m 3 So that it enters the first fracture and propped up the fracture. Then pumping a second fracturing fluid, wherein the second fracturing fluid comprises 1.0 percent by mass of KCl, 0.2 percent by mass of clay stabilizer and a sand type propping agent combination, the sand type propping agent combination comprises 13 percent by mass of natural quartz sand, 16 percent by mass of natural quartz sand and 18 percent by mass of natural quartz sand, the sand type propping agent combination comprises coarse sand with the particle size of 15 meshes, middle sand with the particle size of 30 meshes and fine sand with the particle size of 60 meshes, and the using amount of the sand type propping agent combination is 30m 3 . The pumping speed of the second fracturing fluid is controlled to be 4.0m in sequence during pumping 3 /min，5.5m 3 /min，7.5m 3 And (2) controlling the mass percentage of the sand propping agent in the second fracturing fluid to be 13%, 16% and 18% in sequence, and pumping the second fracturing fluid to 220m 3 . Then, the texture is usedThe third fracturing fluid and the second fracturing fluid remained in the well bore are displaced into the Gao Jiemei reservoir by the displacing fluid with the weight percentage of 1.0 percent of KCl, 0.2 percent of clay stabilizer and the balance of water. Stopping the pump, avoiding well closing, measuring pressure, reasonably controlling flowback parameters, quickly flowback, and controlling the lifting of reservoir pressure and reservoir pollution. Through the fracturing method, the single well gas yield of the coal bed gas reaches 1800m 3 To 3200m 3 Average daily gas production of single well is 2100m 3 Compared with the condition that the area is adjacent to the old well, the stable gas yield of the gas well adopting the fracturing method is 2.5-3 times that of the old well, and the accumulated gas yield is 156 ten thousand meters 3 The stable production period reaches 11-23 months, the dredging type fracturing transformation process effectively improves the single well yield, and improves the overall development effect of the block.
The foregoing is merely an alternative embodiment of the present disclosure, and is not intended to limit the present disclosure, any modification, equivalent replacement, improvement, etc. that comes within the spirit and principles of the present disclosure are included in the scope of the present disclosure.
Claims (8)
1. A method of conducting fracturing of a high rank coal reservoir, the method comprising:
determining the depth range of raw coal in a high-order coal reservoir according to logging data;
perforating in a shaft corresponding to the middle area of the depth range of the primary coal of the high-order coal reservoir, and forming a plurality of holes in the inner wall of the shaft;
injecting a first fracturing fluid through the plurality of perforations to form a first fracture in raw coal of the high-order coal reservoir;
injecting a third fracturing fluid from the plurality of holes, so that a crack propping agent in the third fracturing fluid supports the first crack, wherein the third fracturing fluid is a mixed fluid of the first fracturing fluid and the crack propping agent, and the content of the crack propping agent of the third fracturing fluid is lower than that of the second fracturing fluid;
sequentially and continuously injecting the second fracturing fluid into the first fracture from the plurality of holes according to a first speed, a second speed and a third speed, so that the second fracturing fluid forms a second fracture in the raw coal of the high-order coal reservoir and a fracture propping agent in the second fracturing fluid supports the second fracture, the first fracture is communicated with the second fracture, the second fracturing fluid is a mixed fluid of the first fracturing fluid and the fracture propping agent, the first speed is smaller than the second speed, the second speed is smaller than the third speed,
the mass percent of the crack propping agent of the second fracturing fluid is a first content when the second fracturing fluid is injected at the first speed, the mass percent of the crack propping agent of the second fracturing fluid is a second content when the second fracturing fluid is injected at the second speed, the mass percent of the crack propping agent of the second fracturing fluid is a third content when the second fracturing fluid is injected at the third speed, and the first content is smaller than the second content and the second content is smaller than the third content;
injecting a displacement fluid from within the wellbore, displacing the first fracturing fluid and the second fracturing fluid in the primary coal of the high-order coal reservoir;
stopping injecting liquid into the shaft, and directly returning the liquid without being closed to the well.
2. The method of conducting fracturing of a higher order coal reservoir of claim 1, wherein determining a depth range of raw coal in the higher order coal reservoir from logging data comprises:
acquiring the logging data of different areas in the high-order coal reservoir, wherein the logging data comprises: at least one of resistivity of the high-rank coal reservoir, acoustic time difference of the high-rank coal reservoir, natural gamma value of the high-rank coal reservoir, and density log of the high-rank coal reservoir;
determining a depth range of raw coal in the high-order coal reservoir from the logging data.
3. The method of conducting fracturing of a high-order coal reservoir of claim 2, wherein the determining a depth range of raw coal in the high-order coal reservoir from the logging data comprises:
if the logging data satisfies the region of the first determined relation, determining the depth range of all the regions satisfying the first determined relation in the high-order coal reservoir as the depth range of raw coal in the high-order coal reservoir,
the first determined relationship includes at least one of: the resistivity is greater than 3000 Ω.m, the sonic time difference is between 370 and 410 μs/m, the natural gamma value is between 30 and 80API, and the density log is 1.3g/cm 3 To 1.6g/cm 3 Between them.
4. The method of conducting fracturing of a high-order coal reservoir of claim 1, wherein perforating the wellbore in a middle region of a depth range corresponding to raw coal of the high-order coal reservoir comprises:
and carrying out concentrated perforation in the middle area of the depth range of the primary coal of the high-order coal reservoir in the well bore, wherein the perforation density is 10 holes/m to 20 holes/m, the perforation depth is 2.5m to 3.0m, and the perforation direction is perpendicular to the minimum main stress direction of the coal bed.
5. The method of conducting fracturing of a high-order coal reservoir according to claim 1, wherein the third fracturing fluid comprises: the crack propping agent comprises, by mass, 1.0 to 2.0% of potassium chloride, 0.2 to 0.5% of clay stabilizer, 6.0 to 8.0% of crack propping agent and the balance of water;
the second fracturing fluid comprises: the crack propping agent comprises, by mass, 1.0 to 2.0% of potassium chloride, 0.2 to 0.5% of clay stabilizer, 12 to 20% of crack propping agent and the balance of water.
6. The method of conducting fracturing of a high-order coal reservoir according to claim 1, wherein the fracture propping agent is a sand propping agent, the sand propping agent of the second fracturing fluid comprises three kinds of supporting sand with different grain sizes, wherein the weight percentage of the supporting sand with the smallest grain size is 16.7%, the weight percentage of the supporting sand with the largest grain size is 33.3%, the weight percentage of the supporting sand with the grain size between the supporting sand with the smallest grain size and the supporting sand with the largest grain size is 50.0%,
the grain size of the sand propping agent of the third fracturing fluid is the supporting sand with the grain size between the supporting sand with the smallest grain size and the supporting sand with the largest grain size in the sand propping agent of the second fracturing fluid.
7. The method of conducting fracturing of a high-order coal reservoir according to any one of claims 1 to 6, wherein the first fracturing fluid comprises: the clay stabilizer comprises, by mass, 1.0 to 2.0% of potassium chloride, 0.2 to 0.5% of clay stabilizer and the balance of water.
8. The method of conducting fracturing of a high-order coal reservoir according to any one of claims 1 to 6, further comprising:
measuring wellhead pressure, and determining flowback parameters according to the wellhead pressure;
the determining flowback parameters according to the wellhead pressure comprises:
if the wellhead pressure is greater than 20Mpa, a choke with the diameter of 6mm is adopted for flowback;
if the wellhead pressure is 10Mpa to 20Mpa, a choke with the diameter of 10mm is adopted for flowback;
if the wellhead pressure is 5Mpa to 10Mpa, a choke with the diameter of 12mm is adopted for flowback;
and if the wellhead pressure is less than 5MPa, adopting a 14mm oil nozzle to perform flowback.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN86107208A (en) * | 1985-10-17 | 1987-07-01 | 威廉姆·普尔曼 | Improving one's methods of multiple-stage coal seam fracing |
| CN105317417A (en) * | 2014-07-31 | 2016-02-10 | 中国石油天然气股份有限公司 | Fracturing method of medium-to-high-rank coal bed gas reservoir |
| CN105604534A (en) * | 2016-01-24 | 2016-05-25 | 廊坊开发区中油化油气技术服务有限公司 | Hydraulically affected fracturing process method for increasing production of coal-bed gas reservoir |
| CN106337676A (en) * | 2015-07-07 | 2017-01-18 | 中国石油天然气股份有限公司 | Method of fracturing coal-bed gas reservoir |
| CN109209320A (en) * | 2017-07-06 | 2019-01-15 | 中国石油天然气股份有限公司 | A kind of secondary fracturing method of coal bed gas well |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7735551B2 (en) * | 2004-12-23 | 2010-06-15 | Trican Well Service, Ltd. | Method and system for fracturing subterranean formations with a proppant and dry gas |
-
2020
- 2020-05-09 CN CN202010386635.5A patent/CN113622891B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN86107208A (en) * | 1985-10-17 | 1987-07-01 | 威廉姆·普尔曼 | Improving one's methods of multiple-stage coal seam fracing |
| CN105317417A (en) * | 2014-07-31 | 2016-02-10 | 中国石油天然气股份有限公司 | Fracturing method of medium-to-high-rank coal bed gas reservoir |
| CN106337676A (en) * | 2015-07-07 | 2017-01-18 | 中国石油天然气股份有限公司 | Method of fracturing coal-bed gas reservoir |
| CN105604534A (en) * | 2016-01-24 | 2016-05-25 | 廊坊开发区中油化油气技术服务有限公司 | Hydraulically affected fracturing process method for increasing production of coal-bed gas reservoir |
| CN109209320A (en) * | 2017-07-06 | 2019-01-15 | 中国石油天然气股份有限公司 | A kind of secondary fracturing method of coal bed gas well |
Non-Patent Citations (3)
| Title |
|---|
| 中高煤阶煤层气富集高产区形成模式与地质评价方法;宋岩等;《地学前缘》;20160531;第23卷(第03期);第1-9页 * |
| 煤层气含量影响因素及预测方法;曹军涛等;《西安石油大学学报(自然科学版)》;20130731;第28卷(第04期);第28-34页 * |
| 输送压裂液的物理性质与最小流速的新方程;王松等;《国外油田工程》;20090131;第25卷(第01期);第34-37页 * |
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