CN113123771A - Fracturing method of coal bed gas cluster well - Google Patents
Fracturing method of coal bed gas cluster well Download PDFInfo
- Publication number
- CN113123771A CN113123771A CN202010046979.1A CN202010046979A CN113123771A CN 113123771 A CN113123771 A CN 113123771A CN 202010046979 A CN202010046979 A CN 202010046979A CN 113123771 A CN113123771 A CN 113123771A
- Authority
- CN
- China
- Prior art keywords
- coal seam
- fracturing
- perforation
- sand blasting
- perforating
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000003245 coal Substances 0.000 title claims abstract description 222
- 238000000034 method Methods 0.000 title claims abstract description 54
- 238000005488 sandblasting Methods 0.000 claims abstract description 102
- 239000012530 fluid Substances 0.000 claims abstract description 64
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 46
- 239000007921 spray Substances 0.000 claims description 23
- 238000005086 pumping Methods 0.000 claims description 14
- 238000006073 displacement reaction Methods 0.000 claims description 9
- 238000009434 installation Methods 0.000 claims description 5
- 230000008878 coupling Effects 0.000 claims description 4
- 238000010168 coupling process Methods 0.000 claims description 4
- 238000005859 coupling reaction Methods 0.000 claims description 4
- 238000007789 sealing Methods 0.000 claims description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 26
- 239000004576 sand Substances 0.000 description 22
- 238000004519 manufacturing process Methods 0.000 description 9
- 239000003795 chemical substances by application Substances 0.000 description 8
- 238000007596 consolidation process Methods 0.000 description 7
- 239000012634 fragment Substances 0.000 description 4
- 238000002347 injection Methods 0.000 description 4
- 239000007924 injection Substances 0.000 description 4
- 239000002245 particle Substances 0.000 description 4
- 239000011435 rock Substances 0.000 description 4
- 239000006004 Quartz sand Substances 0.000 description 3
- 238000011049 filling Methods 0.000 description 3
- 238000011010 flushing procedure Methods 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000004568 cement Substances 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 238000005553 drilling Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 238000007790 scraping Methods 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- KXGFMDJXCMQABM-UHFFFAOYSA-N 2-methoxy-6-methylphenol Chemical compound [CH]OC1=CC=CC([CH])=C1O KXGFMDJXCMQABM-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000003795 desorption Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000005011 phenolic resin Substances 0.000 description 1
- 229920001568 phenolic resin Polymers 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Images
Classifications
-
- 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
-
- 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
- E21B43/11—Perforators; Permeators
- E21B43/114—Perforators using direct fluid action on the wall to be perforated, e.g. abrasive jets
-
- 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
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Filling Or Discharging Of Gas Storage Vessels (AREA)
Abstract
The application belongs to the technical field of coal bed gas exploitation, and particularly relates to a fracturing method for a coal bed gas cluster well. According to the method, a perforating pipe column is put into a coal bed gas cluster well, a target coal bed corresponding to the coal bed gas well is subjected to sand blasting and perforating through the perforating pipe column, after the target coal bed is subjected to sand blasting and perforating, the perforating pipe column is put out, the pipe column is pressed down to the coal bed gas well, fracturing fluid is pumped into a jet well hole formed by sand blasting and perforating through the fracturing pipe column, the target coal bed which is subjected to sand blasting and perforating is fractured, the jet well hole can be fractured on the basis of the jet well hole formed by sand blasting and perforating, more coal bed cracks can be generated, and therefore the yield of the coal bed gas cluster well can be improved.
Description
Technical Field
The application belongs to the technical field of coal bed gas exploitation, and particularly relates to a fracturing method for a coal bed gas cluster well.
Background
China has rich coal bed gas resources, but the yield of a single coal bed gas well is low, the exploitation amount of the coal bed gas is far lower than the expected target, and the technical problem is one of important factors for restricting the actual production capacity of the coal bed gas.
A coalbed methane cluster well is a well site where two or more directional groups of wells are planned to be drilled. Fracturing of a coalbed methane cluster well is often required before the coalbed methane cluster well is put into production or after the coalbed methane cluster well is put into production for a period of time. At present, in the related art, when fracturing a coal bed gas cluster well, a casing perforation hydraulic fracturing method is mostly adopted, but the method often cannot select the fracture direction, and the number of coal bed fractures formed after fracturing is small, so that the high yield target is not easy to achieve.
Disclosure of Invention
In view of the above, the present disclosure provides a method for fracturing a coal bed gas cluster well to increase the yield of the coal bed gas cluster well. The method is applied to the coal bed gas cluster well, and comprises the following steps:
putting a perforating pipe column into the coal-bed gas well;
sand blasting and perforating a target coal bed corresponding to the coal bed gas well through a perforating pipe column;
after sand blasting and perforating the target coal seam, putting out a perforating pipe column;
putting a fracturing string into the coal-bed gas well;
and pumping fracturing fluid into the jet well hole formed by the sand blasting perforation through the fracturing pipe column so as to fracture the target coal seam with the sand blasting perforation completed.
In one possible implementation manner, sand blasting and perforating a corresponding target coal seam of a coal seam gas well through a perforating string comprises the following steps:
segmenting a target coal seam;
sand blasting and perforating a first layer section of the target coal layer through the perforating pipe column, and after sand blasting and perforating the first layer section, enabling the perforating pipe column to extend forwards or backwards in the coal-bed gas well so as to position the perforating pipe column to a next layer section of the target coal layer;
and continuously carrying out sand blasting and perforation on the next layer section of the target coal seam through the perforation pipe column until the sand blasting and perforation on the target coal seam are finished.
In one possible implementation, prior to sand blasting each interval of the target coal seam through the perforating string, the method further comprises:
the position of the spray gun installed on the perforating string is checked to ensure that the spray gun avoids the coupling position of the casing, and the spray gun is rotatable.
In one possible implementation, after checking the position of a lance mounted on the perforating string, the method further comprises:
and adjusting the orientation of the spray gun according to the stress magnitude of the stratum or the direction of the pre-designed fracture, so that the spray gun can perform sand blasting perforation along the direction of the maximum horizontal principal stress in the stratum, or the spray gun can perform sand blasting perforation along the direction of the pre-designed fracture.
In one possible implementation, after adjusting the lance orientation, the method further comprises:
and (5) carrying out wellhead installation on the coal-bed gas well.
In one possible implementation, after the coal bed gas well is uphole installed, the method further comprises:
and testing the sealing performance of the pipeline used for carrying out sand blasting perforation on the target coal seam on the ground.
In one possible implementation, the method further includes:
setting the packer while setting the fracturing string into the coal-bed gas well, and segmenting the target coal bed with the sand blasting perforation completed by the packer.
In one possible implementation, pumping a fracturing fluid through a fracturing string into a jet wellbore formed by sand-blast perforation comprises:
injecting fracturing fluid into a fracturing pipe column to fracture a first layer section of a target coal seam which is subjected to sand blasting perforation, wherein the fracturing pipe column is internally provided with a sliding sleeve and a setting ball seat;
after fracturing a first layer section of a target coal seam which is subjected to sand blasting perforation, opening a sliding sleeve, and plugging the fractured layer section by using a setting ball seat;
and continuing fracturing the next layer section of the target coal seam which is subjected to sand blasting until fracturing of the target coal seam which is subjected to sand blasting is completed.
In one possible implementation, the fracturing fluid includes a pad fluid for opening a coal seam fracture and a sand-carrying fluid carrying a proppant for filling into the coal seam fracture to strengthen a wall of the coal seam gas well.
In one possible implementation, the fracturing fluid further comprises a displacement fluid for displacing the residual sand-carrying fluid in the fracturing pipe and casing into the formed coal seam fractures.
The beneficial effects brought by the technical scheme provided by the embodiment of the application at least comprise: through to the perforation tubular column down in the coal bed gas cluster well, through the target coal seam sandblast perforation of this perforation tubular column to coal bed gas well correspondence, after sandblast perforation to this target coal seam, propose the perforation tubular column, and to fracturing tubular column down in the coal bed gas well, pump into fracturing fluid in the injection well hole that forms by sandblast perforation through this fracturing tubular column, in order to carry out the fracturing to the target coal seam that has accomplished sandblast perforation, can carry out the fracturing to this injection well hole on the basis of the injection well hole that sandblast perforation formed, can produce more coal seam cracks, thereby can improve the output of coal bed gas cluster well.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a flow chart of a method for fracturing a coalbed methane cluster well according to a first embodiment of the present disclosure;
FIG. 2 is a flow chart of a method for fracturing a coalbed methane cluster well according to a second embodiment of the present disclosure;
fig. 3 schematically illustrates a fracturing diagram when a target coal seam is fractured by the fracturing method for a coalbed methane cluster well provided by the second embodiment of the application.
Wherein the reference numerals are respectively: 100-fracturing a tubular string; 200-a sliding sleeve; 300-a packer; 400-setting the ball seat; 500-target coal seam with completed perforation; 600-artificial well bottom.
Detailed Description
To make the objects, technical solutions and advantages of the present application more clear, embodiments of the present application will be described in further detail below with reference to the accompanying drawings.
In the related art, when a coal bed gas cluster well is fractured, a casing perforation hydraulic fracturing method is mostly adopted, but the method often cannot select the fracture direction, and the number of the coal bed fractures formed after fracturing is small, so that the high yield target is not easy to achieve. Accordingly, there is a need for a method of fracturing a coalbed methane cluster well that can increase the production of the coalbed methane cluster well.
In a first embodiment, the present application provides a method for fracturing a coal bed gas cluster well, as shown in fig. 1, the method is applied to a coal bed gas cluster well, and the method includes:
s101, placing a perforating string into a coal-bed gas well;
step S102, carrying out sand blasting perforation on a target coal seam corresponding to the coal seam gas well through a perforation pipe column;
step S103, after sand blasting and perforating are carried out on the target coal seam, a perforating pipe column is put forward;
s104, placing a fracturing string into the coal-bed gas well;
and S105, pumping fracturing fluid into the jet well hole formed by sand blasting perforation through the fracturing pipe column so as to fracture the target coal seam with the sand blasting perforation completed.
In one possible implementation manner, sand blasting and perforating a corresponding target coal seam of a coal seam gas well through a perforating string comprises the following steps:
segmenting a target coal seam;
sand blasting and perforating a first layer section of the target coal layer through the perforating pipe column, and after sand blasting and perforating the first layer section, enabling the perforating pipe column to extend forwards or backwards in the coal-bed gas well so as to position the perforating pipe column to a next layer section of the target coal layer;
and continuously carrying out sand blasting and perforation on the next layer section of the target coal seam through the perforation pipe column until the sand blasting and perforation on the target coal seam are finished.
In one possible implementation, prior to sand blasting each interval of the target coal seam through the perforating string, the method further comprises:
the position of the spray gun installed on the perforating string is checked to ensure that the spray gun avoids the coupling position of the casing, and the spray gun is rotatable.
In one possible implementation, after checking the position of a lance mounted on the perforating string, the method further comprises:
and adjusting the orientation of the spray gun according to the stress magnitude of the stratum or the direction of the pre-designed fracture, so that the spray gun can perform sand blasting perforation along the direction of the maximum horizontal principal stress in the stratum, or the spray gun can perform sand blasting perforation along the direction of the pre-designed fracture.
In one possible implementation, after adjusting the lance orientation, the method further comprises:
and (5) carrying out wellhead installation on the coal-bed gas well.
In one possible implementation, after the coal bed gas well is uphole installed, the method further comprises:
and testing the sealing performance of the pipeline used for carrying out sand blasting perforation on the target coal seam on the ground.
In one possible implementation, the method further includes:
setting the packer while setting the fracturing string into the coal-bed gas well, and segmenting the target coal bed with the sand blasting perforation completed by the packer.
In one possible implementation, pumping a fracturing fluid through a fracturing string into a jet wellbore formed by sand-blast perforation comprises:
injecting fracturing fluid into a fracturing pipe column to fracture a first layer section of a target coal seam which is subjected to sand blasting perforation, wherein the fracturing pipe column is internally provided with a sliding sleeve and a setting ball seat;
after fracturing a first layer section of a target coal seam which is subjected to sand blasting perforation, opening a sliding sleeve, and plugging the fractured layer section by using a setting ball seat;
and continuing fracturing the next layer section of the target coal seam which is subjected to sand blasting until fracturing of the target coal seam which is subjected to sand blasting is completed.
In one possible implementation, the fracturing fluid includes a pad fluid for opening a coal seam fracture and a sand-carrying fluid carrying a proppant for filling into the coal seam fracture to strengthen a wall of the coal seam gas well.
In one possible implementation, the fracturing fluid further comprises a displacement fluid for displacing the residual sand-carrying fluid in the fracturing pipe and casing into the formed coal seam fractures.
According to the fracturing method of the coalbed methane cluster well, the perforating pipe column is arranged in the coalbed methane cluster well, the target coalbed corresponding to the coalbed methane well is subjected to sand blasting perforation through the perforating pipe column, after the sand blasting perforation is carried out on the target coalbed, the perforating pipe column is put forward, the pipe column is pressed down in the coalbed methane well, fracturing fluid is pumped into the jet well hole formed by the sand blasting perforation through the fracturing pipe column, the target coalbed with the sand blasting perforation completed is fractured, the jet well hole can be fractured on the basis of the jet well hole formed by the sand blasting perforation, more coalbed cracks can be generated, and therefore the yield of the coalbed methane cluster well can be improved.
In a second embodiment, the present application provides a method for fracturing a coal bed gas cluster well, as shown in fig. 2, the method is applied to a coal bed gas cluster well, and the method includes:
and S201, placing a lower perforating pipe column into the coal-bed gas well.
In the fracturing method of the coalbed methane cluster well provided by this embodiment, before fracturing a target coalbed corresponding to a coalbed methane well, sand blasting and perforation are performed on the coalbed corresponding to the coalbed methane well. Therefore, before fracturing a target coal seam corresponding to the coal seam gas well, a perforating string needs to be put into the coal seam gas well, and the perforating string is provided with a device such as a spray gun or a sand blower which can perforate the target coal seam. When the lower perforating string is placed in the coal-bed gas well, the perforating string can be placed in a casing of the coal-bed gas well, so that a spray gun or a sand blaster on the perforating string can be used for perforating the casing and a cement sheath to communicate a coal-bed gas shaft with a target coal bed. In addition, after the drilling operation of the cluster well is completed in the coal seam, the newly drilled coal seam gas well often contains a large amount of impurities such as silt or broken stones, and the operator also does not know whether the newly drilled coal seam gas well can be smoothly and normally placed into various underground tools, so that the coal seam gas well can be subjected to well dredging, well washing, scraping and pressure testing firstly after the drilling operation of the cluster well is completed in the coal seam. The size of the drift size gauge used during drifting, the flushing liquid and the flushing standard used during flushing, the size of the scraper used during scraping, and the pressure standard used during pressure testing can be selected according to actual production needs.
And S202, performing sand blasting perforation on a target coal seam corresponding to the coal seam gas well through the perforating pipe column.
When the depth of the coal bed gas well is far greater than the length of the perforating string, sand blasting and perforating cannot be performed on a target coal bed corresponding to the coal bed gas well through the perforating string at one time. At this time, step S202 may include the steps of:
and step S2021, segmenting a target coal seam corresponding to the coal seam gas well.
If the casings in the coal-bed gas well are connected through casing collars, a specific method for segmenting the target coal bed may be to segment the target coal bed according to the collar positions of the casings. For example, a section of the target coal seam between a predetermined number of casing collar locations that are adjacent in sequence is considered.
Step S2022, performing sand blasting perforation on the first section of the target coal seam through the perforating string, and after performing sand blasting perforation on the first section, extending the perforating string forwards or backwards in the coal seam gas well so as to position the perforating string to the next section of the target coal seam.
After the target coal seam is segmented, a first segment of the target coal seam may be sand blasted through the perforating string. After sand blasting the first section of the target coal seam through the perforating string, the perforating string can be extended forwards or backwards in the coal seam gas well by lifting or lowering the perforating string so as to position the perforating string to the next interval of the target coal seam. Wherein, a sensing device (such as a collar locator and the like) can be arranged on the perforating string to sense the position of the casing collar, so as to locate the perforating string to the corresponding interval of the target coal seam.
The specific method for sand blasting and perforating the target coal seam by using the perforating pipe column can be as follows: starting a fracturing truck, adding particles such as quartz sand or ceramsite with a preset volume into a sand mixing truck, then injecting high-pressure perforating fluid carrying the particles into a perforating string under the condition that the discharge capacity of the fracturing truck is stable, and ejecting a sleeve and a cement ring through a nozzle or a sand ejector arranged on the perforating string to communicate a coal-bed gas well with a target coal bed. The specific numerical value of the particles such as quartz sand or ceramsite with the preset volume amount can be selected according to actual production needs. In addition, parameters such as fracturing truck displacement and perforation time can be designed in advance to determine whether sand blasting perforation of the target coal seam is finished. For example, when the displacement of the fracturing truck reaches a preset threshold value, or the perforation time reaches a set value, sand blasting perforation of the target coal seam can be considered to be completed.
And step S2023, continuously performing sand blasting and perforation on the next layer section of the target coal seam through the perforation pipe column until the sand blasting and perforation on the target coal seam are completed.
After the perforating string is positioned to the next layer section of the target coal seam, sand blasting and perforating can be continuously carried out on the target coal seam through the perforating string, namely steps S2022-S2023 can be repeated until sand blasting and perforating are finished on the target coal seam.
In one possible implementation, if casings in a coal bed gas well are connected by casing collars, unnecessary incidents are likely to be caused if perforations are made at the collar locations. Therefore, after the perforating string is placed in the casing of the coal-bed gas well, before sand blasting and perforating each interval of the target coal bed through the perforating string, the position of a spray gun or a sand blaster installed on the perforating string can be checked, and the spray gun or the sand blaster is ensured to avoid the coupling position of the casing. Wherein, the lance or the sand blaster arranged on the perforating string can be rotatable, and the rotatable lance or the sand blaster can be rotated within an angle range of 180 degrees or 360 degrees, so that the perforation can be accurately carried out according to the perforation direction required by the actual production by adjusting the angle of the nozzle or the sand blaster. For example, after checking the position of a lance or a sand blaster installed on a perforating string, when selectively perforating a target coal seam with a rotatable lance or sand blaster on the perforating string, the orientation of the lance or sand blaster may be adjusted according to the formation stress level or the pre-designed fracture direction so that the lance or sand blaster can sand blast in the direction of the maximum horizontal principal stress in the formation stress, or so that the lance or sand blaster can sand blast in the pre-designed fracture direction.
In addition, because various pipeline devices such as a blowout pipeline, a circulation pipeline and the like need to be called on the ground during coal bed gas exploitation, after the orientation of a spray gun or a sand blaster installed on a perforating string is adjusted, a wellhead can be installed on the coal bed gas well before a target coal bed is subjected to sand blasting perforation through the perforating string. The specific type of the installed wellhead can be selected according to actual production requirements, such as a KQ65/70 type wellhead or a KQ78/65-105 type wellhead. In addition, after the wellhead installation is carried out on the coal-bed gas well, before the target coal bed is subjected to sand blasting perforation through the perforating pipe column, the sealing performance of various pipelines used for sand blasting perforation of the target coal bed on the ground can be tested firstly, and unnecessary accidents are prevented from occurring when the target coal bed is subjected to sand blasting perforation through the perforating pipe column. When the tightness of each pipeline is tested, the tightness of each pipeline under the pressure which is not less than the highest pumping pressure at the time of fracturing can be tested.
And step S203, after sand blasting and perforating the target coal seam, putting out a perforating string.
And after sand blasting and perforating are finished on the target coal seam through the perforating pipe column, the perforating pipe column is put forward, and the hydraulic jet process of the target coal seam is finished.
And S204, putting a fracturing string into the coal-bed gas well.
After sand blasting perforation of the target coal seam is completed through the perforation string, a jet wellbore formed by the sand blasting perforation can be formed on the target coal seam. At the moment, a fracturing string is put into the coal-bed gas well, and the jet well can be fractured continuously through the fracturing string. In addition, when the depth of the coal bed gas well is far greater than the length of the fracturing string, the fracturing string is placed into the coal bed gas well, and meanwhile, a packer can be set between the fracturing string and the sleeve, so that the packer can segment the target coal bed with sand blasting perforation completed, and the fracturing string can conveniently fracture the target coal bed. It should be noted that each interval obtained by segmenting the target coal seam with sand blasting perforation by the packer may be the same as or different from each interval obtained by segmenting the target coal seam in step S2021. In addition, after a fracturing string is put into the coal-bed gas well, the tightness of various pipelines required by target coal-bed fracturing needs to be detected, and the pressure of the coal-bed gas well needs to be tested.
And S205, pumping fracturing fluid into the jet well hole formed by sand blasting perforation through the fracturing pipe column so as to fracture the target coal seam with the sand blasting perforation completed.
In one possible implementation manner, step S205 may include:
and S2051, injecting fracturing fluid into a fracturing string to fracture the first section of the target coal seam after sand blasting perforation is finished, wherein the fracturing string is provided with a sliding sleeve and a setting ball seat.
Since the packer has been set while the fracturing string is being placed into the coal-bed gas well in step S204, the packer has segmented the target coal seam for which sand-blast perforation has been completed. Therefore, when pumping fracturing fluid through the fracturing string into the jet wellbore formed by sand blasting, the fracturing fluid may first be pumped through the fracturing tubing included in the fracturing string into the first interval of the target coal seam that has been staged by the packer. Wherein the first interval of the target coal seam that has been segmented by the packer may be the interval closest to the bottom of the coal seam gas well. As shown in fig. 3, since the target coal seam has been subjected to sand blast perforation in step S202, injection boreholes formed by sand blast perforation exist on the casing and on the target coal seam at this time. For ease of understanding, in fig. 3, reference numeral 100 denotes a fracturing string or pipe, 200 denotes a sliding sleeve, 300 denotes a packer, 400 denotes a setting ball seat, 500 denotes a target coal seam in which perforation has been completed, and 600 denotes an artificial well bottom (i.e., the bottom of a coal-bed gas well). After pumping the fracturing fluid through the fracturing pipe into the first zone of the target coal seam where the sand blast perforation has been completed, the fracturing fluid may pass through the jet wellbore on the casing into the jet wellbore on the target coal seam. When the fracturing fluid is continuously pumped into the fracturing pipe, the underground fracturing fluid can form certain pressure, and the pressure can drive the fracturing fluid to continuously extrude to the jet well hole on the target coal seam, so that the jet well hole on the target coal seam is continuously extended, the coal seam near the jet well hole is extruded and broken, and more fracturing cracks are formed. After pumping the fracturing fluid into the fracturing pipe for a preset time at a preset displacement, the first section of the target coal seam is considered to be fractured completely. The preset discharge capacity of the fracturing fluid and the preset time required by pumping the fracturing fluid can be set according to actual needs.
In one possible implementation, the fracturing fluid includes a pad fluid and a sand-carrying fluid. The pad fluid is used for opening a coal seam crack, the sand-carrying fluid carries consolidation propping agent, and the consolidation propping agent is used for filling the coal seam crack so as to reinforce the well wall of the coal seam gas well. For example, a fracturing process for a coal seam may include: pumping the pre-fluid and simultaneously increasing the pump pressure to enable the coal seam to reach the fracture pressure so as to open the fracture, and pumping the sand carrying fluid carrying the proppant so as to carry the proppant to the coal seam fracture so as to enable the proppant to prop the coal seam fracture.
After the coal seam fracture is opened by the pad fluid, in order to prevent the formed coal seam fracture from closing in later operations, proppant can be pumped into the formed coal seam fracture through the sand-carrying fluid. Wherein, the proppant can be ceramic particles, quartz sand or consolidation proppant, etc. The surface of the consolidated proppant can be provided with a coating film composed of organic matters (such as phenolic resin), and the coating film can enable the consolidated proppant to mutually consolidate the surfaces of the consolidated proppant to form a stable support strip in a sand-carrying fluid environment after entering the coal seam cracks, so that the coal seam cracks can be prevented from being closed and collapsed as much as possible. In addition, the surface of the consolidated propping agent can be used for cementing coal and rock fragments appearing in the coal seam cracks, so that the coal and rock fragments are prevented from being embedded into the gaps among the consolidated propping agents to block the coal seam cracks.
In one possible implementation, after the sand-carrying fluid is pumped in, there may be a large amount of residual sand-carrying fluid in the fracturing string and casing. At this time, a displacement fluid may be continuously pumped into the fracturing string to displace the residual sand-carrying fluid in the fracturing string and the casing into the formed coal seam fractures, that is, the fracturing fluid may further include a displacement fluid, and the displacement fluid is used to displace the residual sand-carrying fluid in the fracturing string and the casing into the formed coal seam fractures.
And step S2052, after fracturing the first section of the target coal seam which is subjected to sand blasting perforation, opening the sliding sleeve, and plugging the fractured section by using the setting ball seat.
After the residual sand-carrying liquid in the fracturing string and the sleeve is replaced to the formed coal seam crack by the replacement liquid, a sliding sleeve on the fracturing string can be opened, and the fractured interval is sealed by a setting ball seat, so that the fracturing string can conveniently fracture the next interval of the target coal seam.
And step S2053, continuing fracturing the next layer section of the target coal seam with the sand blasting perforation completed until fracturing of the target coal seam with the sand blasting perforation completed is completed.
After fracturing the first section of the target coal seam and plugging the fractured interval by using the setting ball seat, the next section of the target coal seam can be continuously fractured until the fracturing of the target coal seam with sand blasting perforation is completed. The method for fracturing other intervals of the target coal seam is the same as the steps S2051-S2052, and is not described herein again.
According to the fracturing method of the coalbed methane cluster well, the perforating pipe column is arranged in the coalbed methane cluster well, the perforating pipe column is used for carrying out sand blasting perforation on the target coalbed corresponding to the coalbed methane well, after the sand blasting perforation is carried out on the target coalbed, the perforating pipe column is put out, the pipe column is pressed downwards in the coalbed methane well, fracturing fluid is pumped into the jet well hole formed by the sand blasting perforation through the fracturing pipe column, the target coalbed with the sand blasting perforation is fractured, the jet well hole can be fractured on the basis of the jet well hole formed by the sand blasting perforation, more coalbed fractures can be generated, and therefore the yield of the coalbed methane cluster well can be improved. In addition, when sand blasting and perforating are carried out on the target coal seam, the nozzles are used for perforating according to the perforation direction required by actual production, so that the target coal seam can be fractured more effectively according to the predesigned fracturing direction.
After the target coal seam is fractured, the consolidation propping agent is filled into the coal seam fracture formed by fracturing, so that the consolidation propping agent is consolidated in the coal seam fracture to form a stable supporting strip, the coal seam fracture can be prevented from being closed and collapsed, the coal rock fragments appearing in the coal seam fracture can be consolidated on the surface of the consolidation propping agent, the coal rock fragments are prevented from being embedded into the gap between the consolidation propping agents to block the coal seam fracture, and the desorption area of the coal seam and the seepage capacity of the coal seam fracture are greatly increased.
The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.
Claims (10)
1. A method for fracturing a coal bed gas cluster well, wherein the method is applied to the coal bed gas cluster well, and comprises the following steps:
putting a perforating pipe column into the coal-bed gas well;
performing sand blasting perforation on a target coal bed corresponding to the coal bed gas well through the perforation pipe column;
after sand blasting and perforating the target coal seam, putting out the perforating string;
putting a fracturing string into the coal-bed gas well;
pumping a fracturing fluid through the fracturing string into a jet wellbore formed by sand-blasting perforation to fracture the target coal seam after the sand-blasting perforation is completed.
2. The method of claim 1, wherein the sand blasting the corresponding target coal seam of the coal seam gas well through the perforation string comprises:
segmenting the target coal seam;
sand blasting a first section of the target coal seam through the perforating string and extending the perforating string forward or backward in the coal seam gas well after sand blasting the first section to locate the perforating string to a next interval of the target coal seam;
and continuously performing sand blasting and perforation on the next layer section of the target coal seam through the perforation pipe column until the sand blasting and perforation on the target coal seam are completed.
3. The method of claim 2, wherein prior to sand blasting each interval of the target coal seam through the perforating string, the method further comprises:
checking the position of a spray gun installed on the perforating string to ensure that the spray gun avoids the position of a coupling of the casing, wherein the spray gun is rotatable.
4. The method of claim 3, wherein after said checking the position of a lance installed on said perforating string, the method further comprises:
and adjusting the orientation of the spray gun according to the stress magnitude of the stratum or the direction of the pre-designed fracture, so that the spray gun can carry out sand blasting perforation along the direction of the maximum horizontal principal stress in the stratum, or the spray gun can carry out sand blasting perforation along the direction of the pre-designed fracture.
5. The method of claim 4, wherein after the adjusting the lance orientation, the method further comprises:
and carrying out wellhead installation on the coal-bed gas well.
6. The method of claim 5, wherein after the uphole installation of the coalbed methane well, the method further comprises:
and testing the sealing performance of a pipeline used for carrying out sand blasting perforation on the target coal seam on the ground.
7. The method of claim 1, further comprising:
setting a packer while setting the fracturing string into the coal-bed gas well, wherein the packer segments the target coal bed on which sand-blasting perforation is finished.
8. The method of claim 7, wherein pumping a fracturing fluid through the fracturing string into a jet wellbore formed by sand-blast perforation comprises:
injecting fracturing fluid into the fracturing string to fracture the first section of the target coal seam after sand blasting perforation is completed, wherein the fracturing string is provided with a sliding sleeve and a setting ball seat;
after fracturing a first stratum of the target coal seam which is subjected to sand blasting perforation, opening the sliding sleeve, and plugging the fractured stratum by using the setting ball seat;
and continuing fracturing the next layer section of the target coal seam which is subjected to sand blasting until fracturing of the target coal seam which is subjected to sand blasting is completed.
9. The method of any one of claims 1 to 8, wherein the fracturing fluid comprises a pad fluid and a sand-carrying fluid, the pad fluid is used to open a coal seam fracture, and the sand-carrying fluid carries a proppant, and the proppant is used to fill the coal seam fracture to reinforce a wall of the coal seam gas well.
10. The method of claim 9, wherein the fracturing fluid further comprises a displacement fluid for displacing residual sand-laden fluid in the fracturing tubular and casing into the formed coal seam fractures.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010046979.1A CN113123771A (en) | 2020-01-16 | 2020-01-16 | Fracturing method of coal bed gas cluster well |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010046979.1A CN113123771A (en) | 2020-01-16 | 2020-01-16 | Fracturing method of coal bed gas cluster well |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113123771A true CN113123771A (en) | 2021-07-16 |
Family
ID=76771691
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010046979.1A Pending CN113123771A (en) | 2020-01-16 | 2020-01-16 | Fracturing method of coal bed gas cluster well |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113123771A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116733432A (en) * | 2023-05-09 | 2023-09-12 | 陕西省煤层气开发利用有限公司 | Transformation process method for deep coal bed gas fracturing |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106285601A (en) * | 2016-08-12 | 2017-01-04 | 中国石油集团渤海钻探工程有限公司 | Cave and fracturing integrated yield-increasing technique method are made in the injection of coal bed gas well abrasive perforating |
| CN107387034A (en) * | 2017-08-30 | 2017-11-24 | 中煤科工集团西安研究院有限公司 | Non- well cementing casing pipe completion coal bed gas horizontal well pumping method |
| US20180171769A1 (en) * | 2015-07-17 | 2018-06-21 | Halliburton Energy Services, Inc. | Structure For Fluid Flowback Control Decision Making And Optimization |
| CN108661618A (en) * | 2017-03-31 | 2018-10-16 | 中国石油天然气股份有限公司 | Reservoir transformation method for L type horizontal well of coal bed gas |
| CN110005374A (en) * | 2019-03-26 | 2019-07-12 | 山西沁盛煤层气作业有限责任公司 | A kind of coal bed gas well one-trip string multilayer partial pressure reforming technology |
-
2020
- 2020-01-16 CN CN202010046979.1A patent/CN113123771A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20180171769A1 (en) * | 2015-07-17 | 2018-06-21 | Halliburton Energy Services, Inc. | Structure For Fluid Flowback Control Decision Making And Optimization |
| CN106285601A (en) * | 2016-08-12 | 2017-01-04 | 中国石油集团渤海钻探工程有限公司 | Cave and fracturing integrated yield-increasing technique method are made in the injection of coal bed gas well abrasive perforating |
| CN108661618A (en) * | 2017-03-31 | 2018-10-16 | 中国石油天然气股份有限公司 | Reservoir transformation method for L type horizontal well of coal bed gas |
| CN107387034A (en) * | 2017-08-30 | 2017-11-24 | 中煤科工集团西安研究院有限公司 | Non- well cementing casing pipe completion coal bed gas horizontal well pumping method |
| CN110005374A (en) * | 2019-03-26 | 2019-07-12 | 山西沁盛煤层气作业有限责任公司 | A kind of coal bed gas well one-trip string multilayer partial pressure reforming technology |
Non-Patent Citations (4)
| Title |
|---|
| 万仁溥等编译: "《水平井开采技术》", 31 March 1995, 石油工业出版社 * |
| 刘营等: "水力喷砂分段压裂工艺在U型煤层气井中的应用", 《钻采工艺》 * |
| 方世跃主编: "《煤层气井建井工程》", 31 January 2015, 徐州：中国矿业大学出版社 * |
| 黄桢等: "《川渝地区页岩气水平井钻完井技术》", 30 September 2018, 重庆大学出版社 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116733432A (en) * | 2023-05-09 | 2023-09-12 | 陕西省煤层气开发利用有限公司 | Transformation process method for deep coal bed gas fracturing |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| AU2020101047A4 (en) | Method for filling underground cavity in bedrock by grouting and hydraulic filling device | |
| CN110953015B (en) | Soft low-permeability coal seam long-drill-hole directional segmented fracturing efficient gas extraction method | |
| US8287050B2 (en) | Method of increasing reservoir permeability | |
| US8313152B2 (en) | Recovery of bitumen by hydraulic excavation | |
| CN109763804B (en) | Staged temporary plugging fracturing method for horizontal well | |
| RU2431037C2 (en) | Method and system for processing of underground formation with use of deviation of processing fluid media (versions) | |
| CN111535791B (en) | Efficient gas extraction method for broken soft low-permeability coal seam well upper and lower combined fracturing area | |
| CN110318674B (en) | Method for preventing outburst caused by cracking of roadway roof | |
| CA2752461C (en) | Enhanced permeability subterranean fluid recovery system and methods | |
| CN101835953A (en) | Well construction using small laterals | |
| RU2601881C1 (en) | Method of layer multiple hydraulic fracturing in inclined borehole | |
| CN104790873A (en) | Soft rock and soil layer jet flow guiding hole forming-chamfering-hole collapse preventing integrated drilling method | |
| CN109025940B (en) | CO for tight oil reservoir2Fracturing oil displacement integrated oil extraction method | |
| CN103603643A (en) | Coal bed gas U-shaped well staged fracturing exploitation technology | |
| CN103742188A (en) | Coal mine pump drainage gas well and drilling method thereof | |
| CN110410053B (en) | Coal mine roof pressure relief method based on eyelet supporting | |
| CN102619496B (en) | Method for layering, stage multi-level blasting, hole expanding and crack expanding of oil-gas-bearing rock | |
| CN112593912B (en) | Coal bed gas horizontal well power expanding, pressure relief and permeability increase extraction method | |
| CN113123771A (en) | Fracturing method of coal bed gas cluster well | |
| CN105756591A (en) | Coal bed gas well completion method | |
| CN112431579A (en) | Preset small-diameter pipe internal fracturing device and method for side drilling well and small-hole well | |
| CN114837608B (en) | Method for reconstructing mining overburden rock water barrier by multi-section graded grouting | |
| CN110805409A (en) | Expansion pipe plugging method based on repeated fracturing cased well | |
| CN114607318A (en) | Fracturing cooperative construction method for combined production and drilling of multi-layer horizontal well for deep coal bed methane | |
| CN113123762A (en) | Fracturing method for coal bed gas multi-branch horizontal well |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210716 |