CN113356827A - Radial well system and oil well system for constructing artificial spacer - Google Patents
Radial well system and oil well system for constructing artificial spacer Download PDFInfo
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- CN113356827A CN113356827A CN202010153059.XA CN202010153059A CN113356827A CN 113356827 A CN113356827 A CN 113356827A CN 202010153059 A CN202010153059 A CN 202010153059A CN 113356827 A CN113356827 A CN 113356827A
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- 239000003129 oil well Substances 0.000 title abstract description 11
- 125000006850 spacer group Chemical group 0.000 title description 2
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 75
- 238000004519 manufacturing process Methods 0.000 claims abstract description 64
- 230000015572 biosynthetic process Effects 0.000 claims abstract description 31
- 238000002347 injection Methods 0.000 claims abstract description 29
- 239000007924 injection Substances 0.000 claims abstract description 29
- 238000005192 partition Methods 0.000 claims abstract description 23
- 239000012530 fluid Substances 0.000 claims abstract description 9
- 230000004888 barrier function Effects 0.000 claims abstract description 4
- 238000004891 communication Methods 0.000 claims abstract description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 51
- 238000006073 displacement reaction Methods 0.000 claims description 3
- 230000005012 migration Effects 0.000 abstract description 3
- 238000013508 migration Methods 0.000 abstract description 3
- 238000000034 method Methods 0.000 description 27
- 239000003921 oil Substances 0.000 description 17
- 230000000694 effects Effects 0.000 description 6
- 235000015110 jellies Nutrition 0.000 description 6
- 239000008274 jelly Substances 0.000 description 6
- 238000011161 development Methods 0.000 description 5
- 230000008569 process Effects 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 3
- 238000004364 calculation method Methods 0.000 description 3
- 238000010276 construction Methods 0.000 description 3
- 239000000499 gel Substances 0.000 description 3
- 230000002401 inhibitory effect Effects 0.000 description 3
- 238000011084 recovery Methods 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 2
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- 239000000243 solution Substances 0.000 description 2
- NAWXUBYGYWOOIX-SFHVURJKSA-N (2s)-2-[[4-[2-(2,4-diaminoquinazolin-6-yl)ethyl]benzoyl]amino]-4-methylidenepentanedioic acid Chemical compound C1=CC2=NC(N)=NC(N)=C2C=C1CCC1=CC=C(C(=O)N[C@@H](CC(=C)C(O)=O)C(O)=O)C=C1 NAWXUBYGYWOOIX-SFHVURJKSA-N 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000005465 channeling Effects 0.000 description 1
- 230000006837 decompression Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 239000006260 foam Substances 0.000 description 1
- 239000004088 foaming agent Substances 0.000 description 1
- 239000000295 fuel oil Substances 0.000 description 1
- 239000003292 glue Substances 0.000 description 1
- 230000005764 inhibitory process Effects 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000013178 mathematical model Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/30—Specific pattern of wells, e.g. optimising the spacing of wells
- E21B43/305—Specific pattern of wells, e.g. optimising the spacing of wells comprising at least one inclined or horizontal well
-
- 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
- E21B33/00—Sealing or packing boreholes or wells
- E21B33/10—Sealing or packing boreholes or wells in the borehole
- E21B33/13—Methods or devices for cementing, for plugging holes, crevices or the like
-
- 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
- E21B43/32—Preventing gas- or water-coning phenomena, i.e. the formation of a conical column of gas or water around wells
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)
- Consolidation Of Soil By Introduction Of Solidifying Substances Into Soil (AREA)
Abstract
The invention provides a radial well system and an oil well system for constructing an artificial partition. A radial well system for constructing an artificial barrier includes a plurality of radial wells projecting from a circumferential wall of a production well in a radial direction of the production well and in fluid communication with the production well to receive plugging agent flowing through the production well, the plurality of radial wells being spaced apart in a circumferential direction of the production well; wherein the number of the plurality of radial wells is related to a maximum distance that the plugging agent will seep in the formation and a length of the radial well. According to the invention, the injection pressure is reduced by arranging a plurality of radial wells communicated with the oil production well, and a channel for constructing the high-speed migration of the plugging agent is formed, so that the purposes of injecting more plugging agents within the same curing time of the plugging agent and effectively improving the laying area and strength of the artificial partition plate are finally achieved.
Description
Technical Field
The invention relates to the technical field of oil development and extraction engineering, in particular to a radial well system for constructing an artificial partition plate and an oil well system comprising the radial well system.
Background
In the later stage of the development of the bottom water reservoir, the bottom water surface is unevenly raised due to the fact that the bottom hole pressure of the oil production well is lower than the formation pressure, and therefore bottom water coning is caused. Bottom water coning can cause flooding of the oil production well, so that oil production of the oil production well is rapidly reduced, water content of the oil production well continuously rises, a large amount of residual oil in a stratum is not effectively produced, and oil field development efficiency is affected.
Currently, there are three main methods for preventing and controlling bottom water coning:
the first is to block the water egress level by running downhole equipment. In chinese patent application CN2777192Y entitled "water shutoff tubular column" published on 3.5.2006, a special device is disclosed to replace the conventional upper and lower layer packer to plug the water producing layer, so as to realize the plugging of bottom water coning. The method only carries out water producing layer plugging on a well structure and does not carry out plugging measures in a stratum, so the method is only suitable for plugging a pure water layer and has limited applicability.
The second is to complete the well using a horizontal well and to fit a corresponding specially made string. In chinese patent application CN101655007A entitled "a high-efficiency pressure-control slow-water-cone horizontal well completion technology" published 24.2.2010, it is disclosed that a fluid flow line in the production process of a horizontal well is changed by completing the horizontal well and adopting an irregular production casing or tubular column, so as to finally achieve the purpose of reducing the pressure in the horizontal well section in a balanced manner, forming a uniform water ridge, and slowing down the bottom water coning. A similar technical solution is also disclosed in chinese patent application CN103122760A entitled "completion string for delaying bottom water coning" published on 29.5.2013. The scheme has certain requirements on the well completion form and cannot be applied to a vertical well, the scheme realizes pressure equalization of a horizontal section by changing equipment and changing a fluid flow line, and is difficult to adjust along with the development process in actual operation, and the applicability is poor.
And the third method is to construct an artificial partition plate by injecting a chemical plugging agent to realize the plugging of the water-containing reservoir and the elimination of the formed water cone. In chinese patent application CN1560428A entitled "decision method for water shutoff of bottom water reservoir" published on 5.1.2005, evaluation of degree of flooding, determination of position of remaining artificial partition, and screening principle of plugging agent were proposed, and finally a systematic decision method for water shutoff was formed. In the Chinese patent application CN101747879A entitled "thin-layer reservoir bottom water control coning partition plate and injection method thereof" published on 6/23/2010, a plugging agent formula is optimized, the injection sequence of different working fluids is proposed, the change of the flow direction of bottom water is realized, and the recovery ratio of the bottom water reservoir is improved. In chinese patent application CN106150466A entitled "method for using gel foaming agent for inhibiting bottom water coning in heavy oil thermal recovery" published in 2016, 11, 23, a method for forming a front slug by injecting nitrogen gas first and then injecting nitrogen gas-gel foam is proposed, which achieves the purpose of inhibiting bottom water coning and balancing formation pressure, and improves the reservoir development effect.
According to the current experience, the construction of the artificial baffle in the third method is a more effective measure for solving the bottom water coning. However, the method focuses on the optimization of the formula of the plugging agent and the construction process, and adopts a method of injecting the plugging agent into an oil well in a general way during field operation, and the plugging agent radially seeps into the stratum by taking a shaft as a circle center depending on the flowing characteristic of the plugging agent. Therefore, the artificial partition board has certain limitation on the laying range and the water retaining effect under the influence of the self characteristics of the plugging agent and the stratum heterogeneity. The plugging agent used by the artificial partition board is mainly a strong jelly continuous phase plugging agent, the plugging agent is influenced by the gelling time, and the effective injection time of the plugging agent into the stratum cannot exceed the gelling time (the jelly cannot flow after being gelled), so that the injection volume of the plugging agent and the laying range of the formed artificial partition board are greatly limited. In addition, the bottom water reservoir has heterogeneity on the plane, the plugging agent can flow along the high permeable layer by the aid of the general injection of the plugging agent, an ideal uniform laying shape cannot be formed, the bottom water can flow around the uninjected stratum of the plugging agent and reenters the oil well to cause flooding, and the water plugging effect is seriously influenced.
In addition, due to the fact that the pressure gradient of the stratum near the oil well is large, the problems that the injection pressure is large, the injection amount of the plugging agent is small and the like exist in the general injection process, the plugging agent cannot enter the deep part of the stratum, and the laying range of the artificial partition plate is limited to a certain extent.
In conclusion, the artificial partition plate for the bottom water reservoir structure has the following defects: firstly, the injection amount of the plugging agent is limited by the gelling time of the plugging agent, and the laying range of the artificial partition plate is limited; the heterogeneity of the stratum can cause the channeling of the plugging agent, and an ideal uniform laying shape cannot be formed; and thirdly, the pressure gradient of the stratum near the oil well is large, so that the injection pressure of the plugging agent is large, the plugging agent is difficult to enter the deep part of the stratum, and the laying range of the artificial partition plate is limited. Therefore, a more efficient and reliable method for laying the artificial partition plates is needed to be designed, and support is provided for improving the recovery ratio.
Disclosure of Invention
The present invention provides a radial well system for constructing artificial barriers that addresses at least some of the above-identified problems.
The present invention also provides an oil well system employing the improved radial well system.
According to an embodiment of the present invention, there is provided a radial well system for constructing an artificial barrier, including a plurality of radial wells projecting from a circumferential wall of a production well in a radial direction of the production well and in fluid communication with the production well to receive plugging agent flowing through the production well, the plurality of radial wells being spaced apart in a circumferential direction of the production well; wherein the number of the plurality of radial wells is related to a maximum distance that the plugging agent will seep in the formation and a length of the radial well.
In some embodiments, the number of the plurality of radial wells is obtained by the following formula:
where n is the number of radial wells, L is the length of the radial well, rmaxIs the most seepage of the plugging agent into the stratum from the end of the radial well far away from the oil production wellA large distance.
In some embodiments, the maximum distance that the plugging agent seeps into the formation from the end of the radial well remote from the production well is obtained by the following equation:
wherein alpha is the flow-dividing coefficient of the plugging agent along the radial well, Q is the injection displacement of the plugging agent, n is the number of the radial wells, phi is the porosity, L is the length of the radial well, and T is the time required for the plugging agent to solidify to form the artificial partition.
In some embodiments, the length of the radial well is obtained by the following equation:
L≥a·rG'，
where L is the length of the radial well, a is the redundancy factor, rG' is the distance between the location of the formation and the production well having a breakthrough pressure gradient corresponding to the breakthrough pressure gradient of the plugging agent.
In some embodiments, the distance between the formation location and the production well is obtained by the following equation:
wherein, PinjFor bottom hole pressure of water injection well, PwIs the bottom hole pressure of the production well, rinjIs the distance between the production well and the injection well, rwIs the radius of the well bore of the oil production well, and G' is the breakthrough pressure gradient of the plugging agent.
In some embodiments, 1.1 ≦ a ≦ 1.3.
In some embodiments, the plurality of radial wells includes at least three radial wells evenly spaced circumferentially of the production well.
In some embodiments, for the heterogeneous bottom water reservoir, the plurality of radial wells comprises at least two sets of radial wells symmetrically arranged on opposite sides of the production well.
In some embodiments, each of the at least two sets of radial wells comprises one or two radial wells.
There is also provided, in accordance with an embodiment of the present invention, a well system including a production well, the well system further including the aforementioned radial well system.
Aiming at the problems of limited laying range and unsatisfactory laying shape of the artificial clapboard caused by the conventional oil well general plugging agent injection, the invention reduces the injection pressure by drilling a plurality of radial wells at the bottom of the well and simultaneously forms a channel for constructing high-speed migration of the plugging agent, finally achieves the purposes of injecting more plugging agents within the same plugging agent curing time and effectively improving the laying area and strength of the artificial clapboard, and has important significance for inhibiting bottom water coning of a bottom water reservoir.
Preferred features of the invention are described in part below and in part will be apparent from the description.
Drawings
Embodiments of the present disclosure are described in detail below with reference to the attached drawing figures, wherein:
FIG. 1 is a schematic top view of a well system according to an embodiment of the invention;
FIG. 2 is a schematic illustration of radial well number calculation according to an embodiment of the present invention;
fig. 3-6 are schematic diagrams of different configurations of a radial well according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the following detailed description and accompanying drawings. The exemplary embodiments and descriptions of the present invention are provided to explain the present invention, but not to limit the present invention.
As shown in fig. 1, according to an embodiment of the present invention, an oil well system includes a production well 10, a water injection well (not shown), and a radial well system, wherein the radial well system includes a plurality of radial wells 20 arranged at intervals in a circumferential direction of the production well 10. Each radial well 20 is connected to the production well 10 at one end and extends radially away from the production well 10 at the other end. The radial well 20 is in fluid communication with the production well 10, and plugging agent injected from the production well 10 may enter the radial well 20 through the production well 10 and seep from the radial well 20 into the formation. After the plugging agent is solidified, an artificial partition board paved in the stratum around the lower part of the oil production well 10 can be formed, and the influence of bottom water coning inhibition of a bottom water oil reservoir on oil exploitation is prevented.
According to an embodiment of the invention, the length of the radial well 20 is determined by:
the laying of the bottom water reservoir artificial clapboard mainly depends on the flow characteristic of the jelly before gelling. For the jelly glue artificial partition plate (with breakthrough pressure gradient of G ') with certain strength, the throwing position at least needs to be deeply arranged at the position corresponding to the stratum pressure gradient of G'. The length of the radial well is therefore dependent on the strength of the plugging agent used and the formation pressure gradient profile and can be determined according to equation (1):
L≥a·rG' (1)
wherein L is the radial well length (cm), a is the redundancy coefficient, rG'The location of the formation or the distance between the point at which the formation is located and the production well 10, which has a breakthrough pressure gradient corresponding to the breakthrough pressure gradient of the plugging agent, (cm).
In some embodiments, a ranges from 1.1 to 1.3, e.g., 1.1, 1.2, or 1.3.
To facilitate the calculation of the formation pressure gradient, the following assumptions are made: fluid seepage in the water flow dominance strip is regarded as single-phase flow of water, and both fluid and porous medium are incompressible for stable flow and obey Darcy's law. The planar radial flow formation pressure gradient is then:
in the formula (I), the compound is shown in the specification,
is the formation pressure gradient (Pa/m), PinjFor bottom hole pressure (Pa), P of water injection wellwIs the bottom hole pressure (Pa), r of the production well 10injIs the distance (m), r, between the production well 10 and the injection wellwIs the shaft radius (m) of the oil production well 10, and r is any point between the oil production well 10 and the water injection well10 (m) between.
Let the breakthrough pressure gradient of equation (2) with its end equal to the plugging agent be G', the location of the formation or the distance between the point of the formation and the production well 10 having the breakthrough pressure gradient corresponding to the breakthrough pressure gradient of the plugging agent can be found:
finishing to obtain:
the length of the radial well 20 is then:
according to an embodiment of the invention, a radial well formation artificial diaphragm plane flow model is established by the following method:
as shown in fig. 1, a radial well formation artificial diaphragm plane flow model is established. The arrows in the figure show the flowing direction of the plugging agent.
Assuming that the radial well has infinite flow conductivity, jelly is injected at constant discharge, and taking a single radial well as an example, a mathematical model of the injected jelly along the radial well for stabilizing seepage is as follows:
in the formula (I), the compound is shown in the specification,
is the radial pressure gradient (Pa/m) along the radial well 20, RradRadius (m), R of the radial well 20LIs the radial flow distance (m), P, of the plugging agent from the end of the radial well 20 away from the production well 10 (or referred to as the "fingered end") to the formationLIs the formation pressure at the finger end of the radial well 20Force (Pa), α being the flow-dividing coefficient of the injected plugging agent along the radial well 20, Q being the injected displacement (m) of the plugging agent3/s)，
Is the average viscosity (mPa.s) of the plugging agent during injection, and k is the formation permeability (um)2) L is the length (m) of the radial well 20, and r is the distance (m) from any point on the finger tip streamline of the radial well 20 to the finger tip of the radial well 20.
Solving the step (6) to obtain the pressure at any point on the finger tip streamline of the radial well 20 as:
the seepage velocity of the plugging agent in the stratum is as follows:
equation (8) is the calculated seepage velocity of the plugging agent in the formation based on darcy's law, and the average real flow velocity of the plugging agent particles in the formation is related to the seepage velocity as follows:
wherein phi is porosity; μ is the true flow rate, m/s.
The variables can be separated for the above formula:
the time taken for the plugging agent particles to migrate from the radial well 20 to the water flow dominant band boundary is:
integrating the formula (10) to obtain a calculation formula of the migration distance of the plugging agent in the stratum within a certain time;
wherein r is the distance (m) between the front of the plugging agent seeping from the finger end of the radial well 20 to the formation and the finger end of the radial well 20, and n is the number of the radial wells 20.
In some embodiments, the radius R of the radial well 20rad3-5cm, negligible compared to the formation, then (12) can be simplified as:
then the maximum distance that the plugging agent migrates in the formation from the fingertip streamlines of the radial well 20 during T before the plugging agent solidifies (e.g., gels or sets) is:
according to an embodiment of the invention, the number of radial wells is obtained by:
in order to allow the plugging agent to be evenly spread around the production well 10, a certain number of radial wells 20 need to be arranged reasonably in a plane. As shown in FIG. 2, assuming n radial wells 20 are in the same plane, it can be seen from equation (14) that the maximum distance AB that the plugging agent will seep into the formation along the fingertips (point B shown in the figure) of the radial wells 20 is r before the plugging agent solidifiesmaxFrom equation (5), the shortest length OB of the radial well 20 is L. For n radial wells 20, the included angle between two adjacent radial wells 20
The angle between OA and OB is
Within the right-angled triangle OAB there is,
namely:
the number of radial wells 20 can be determined according to equation (15).
According to the embodiment of the invention, the artificial partition board for radial well construction can guide the injection of the plugging agent by using the radial well, so that the artificial partition board is more uniformly laid, and the laying range is expanded. The plurality of radial wells 20 may be formed in a variety of arrangements or configurations depending on the nature of the bottom water reservoir.
For a homogeneous bottom water reservoir, for example, a radial well arrangement as shown in fig. 3 and 4 may be formed. As shown in fig. 3, three radial wells 20 are uniformly spaced along the circumferential direction of the oil production well 10, and the included angle between two adjacent radial wells 20 is 120 °. As shown in fig. 4, four radial wells 20 are uniformly spaced along the circumferential direction of the oil production well 10, the four radial wells 20 are integrally arranged in a cross shape, and the included angle between two adjacent radial wells 20 is 30 °. Although only three radial wells and four radial well arrangements are shown, those skilled in the art will appreciate that the number of radial wells can be increased or decreased as desired and with reference to the above equations.
For heterogeneous bottom water reservoirs, for example, a radial well arrangement as shown in fig. 5 and 6 may be formed. As shown in fig. 5, two radial wells 20 are arranged in central symmetry on opposite sides of the production well 10 and have a straight configuration as a whole. As shown in fig. 6, there are one set of radial wells on each of opposite sides of the production well 10, and two sets of radial wells are symmetrically disposed on opposite sides of the production well 10, each set of radial wells including two radial wells 20. Although the figure shows an arrangement of one radial well or two radial wells in a set of radial wells on one side of the production well, it will be understood by those skilled in the art that the number of radial wells may be increased or decreased as desired and with reference to the above formula.
The radial well system according to the present invention can achieve the following effects:
(1) the bottom water reservoir artificial partition plate laying plugging agent is changed from a general injection method to radial well injection, so that the effect of uniform laying is achieved.
(2) In the same curing time, the radial well can increase the injection amount and the spread range of the plugging agent, improve the strength of the artificial partition plate and enlarge the area of the artificial partition plate.
(3) The water conservancy diversion ability of radial well is very strong, can regard as the pipe flow, compares in the stratum seepage flow, greatly reduced to the deep injection pressure in stratum, play the effect of decompression increase notes.
While various embodiments of the invention have been described herein, the description of the various embodiments is not intended to be exhaustive or to limit the invention to the precise forms disclosed, and features and components that are the same or similar to one another may be omitted for clarity and conciseness. The particular features, structures, materials, or characteristics of the various embodiments may be combined in any suitable manner in any one or more embodiments or examples herein. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.
As used herein, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exhaustive, such that a process, method, article, or apparatus that comprises a list of elements may include those elements but do not exclude the presence of other elements not expressly listed.
Exemplary systems and methods of the present invention have been particularly shown and described with reference to the foregoing embodiments, which are merely illustrative of the best modes for carrying out the systems and methods. It will be appreciated by those skilled in the art that various changes in the embodiments of the systems and methods described herein may be made in practicing the systems and/or methods without departing from the spirit and scope of the invention as defined in the appended claims. It is intended that the following claims define the scope of the system and method and that the system and method within the scope of these claims and their equivalents be covered thereby. The above description of the present system and method should be understood to include all new and non-obvious combinations of elements described herein, and claims may be presented in this or a later application to any new and non-obvious combination of elements. Moreover, the foregoing embodiments are illustrative, and no single feature or element is essential to all possible combinations that may be claimed in this or a later application.
Claims (10)
1. A radial well system for constructing an artificial barrier, comprising a plurality of radial wells projecting from a circumferential wall of a production well in a radial direction of the production well and in fluid communication with the production well for receiving plugging agent flowing through the production well, the plurality of radial wells being spaced circumferentially of the production well;
wherein the number of the plurality of radial wells is associated with a maximum distance that the plugging agent will seep in the formation and a length of the radial well.
2. The radial well system of claim 1, wherein the number of the plurality of radial wells is obtained by the formula:
wherein n is the number of the plurality of radial wells, L is the length of the radial well, rmaxThe maximum distance for which the plugging agent will seep into the formation from the end of the radial well remote from the production well.
3. The radial well system of claim 2, wherein the maximum distance that the plugging agent seeps into the formation from the end of the radial well remote from the production well is obtained by the following equation:
wherein α is a flow-dividing coefficient of the plugging agent along the radial well, Q is an injection displacement of the plugging agent, n is the number of the radial wells, Φ is a porosity, L is a length of the radial well, and T is a time required for the plugging agent to solidify to form the artificial partition.
4. The radial well system according to any one of claims 1 to 3, wherein the length of the radial well is obtained by the following formula:
L≥a·rG'，
wherein L is the length of the radial well, a is a redundancy coefficient, rG'Is the distance between the location of the formation having a breakthrough pressure gradient corresponding to the breakthrough pressure gradient of the plugging agent and the production well.
5. The radial well system of claim 4, wherein the distance between the formation location and the production well is obtained by the formula:
wherein, PinjFor bottom hole pressure of water injection well, PwIs the bottom hole pressure of the production well, rinjIs the distance between the production well and the injection well, rwAnd G' is the breakthrough pressure gradient of the plugging agent.
6. The radial well system of claim 4, wherein a is 1.1 ≦ 1.3.
7. The radial well system of any one of claims 1 to 6, wherein the plurality of radial wells comprises at least three radial wells arranged at regular intervals in a circumferential direction of the production well.
8. The radial well system of any one of claims 1 to 6, wherein for a heterogeneous bottom water reservoir, the plurality of radial wells comprises at least two sets of radial wells symmetrically arranged on opposite sides of the production well.
9. The radial well system of claim 8, wherein each of the at least two sets of radial wells comprises one or two radial wells.
10. A well system comprising a production well, characterized in that it further comprises a radial well system according to any of claims 1 to 9.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101139920A (en) * | 2007-10-26 | 2008-03-12 | 辽河石油勘探局 | Dibasic composite horizontal well bottom water plugging technique |
| CN103104254A (en) * | 2013-01-24 | 2013-05-15 | 西南石油大学 | Multifunctional oil reservoir simulation experiment device and experiment method thereof |
| CN206158727U (en) * | 2016-11-07 | 2017-05-10 | 西南石油大学 | Visual bottom water reservoir modeling develop experimental device |
| CA3008545A1 (en) * | 2017-06-27 | 2018-12-27 | Cenovus Energy Inc. | Heavy oil solvent recovery processes using artificially injected composite barriers |
| CN110344803A (en) * | 2019-06-18 | 2019-10-18 | 中国石油天然气股份有限公司 | A kind of control water fracturing yield increasing method of rock-fragment sandstone bottom water gas-bearing formation |
-
2020
- 2020-03-06 CN CN202010153059.XA patent/CN113356827A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101139920A (en) * | 2007-10-26 | 2008-03-12 | 辽河石油勘探局 | Dibasic composite horizontal well bottom water plugging technique |
| CN103104254A (en) * | 2013-01-24 | 2013-05-15 | 西南石油大学 | Multifunctional oil reservoir simulation experiment device and experiment method thereof |
| CN206158727U (en) * | 2016-11-07 | 2017-05-10 | 西南石油大学 | Visual bottom water reservoir modeling develop experimental device |
| CA3008545A1 (en) * | 2017-06-27 | 2018-12-27 | Cenovus Energy Inc. | Heavy oil solvent recovery processes using artificially injected composite barriers |
| CN110344803A (en) * | 2019-06-18 | 2019-10-18 | 中国石油天然气股份有限公司 | A kind of control water fracturing yield increasing method of rock-fragment sandstone bottom water gas-bearing formation |
Non-Patent Citations (1)
| Title |
|---|
| 刘晓强: "边底水油藏径向钻孔控水稳油技术研究", 《硕士电子期刊》 * |
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