CN113279723B - Temporary plugging method in artificial crack of shale oil fracturing - Google Patents
Temporary plugging method in artificial crack of shale oil fracturing Download PDFInfo
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- 239000003079 shale oil Substances 0.000 title claims abstract description 30
- 238000000034 method Methods 0.000 title claims abstract description 25
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 48
- 238000006073 displacement reaction Methods 0.000 claims abstract description 15
- 238000010276 construction Methods 0.000 claims abstract description 10
- 239000007788 liquid Substances 0.000 claims abstract description 9
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 9
- 239000011229 interlayer Substances 0.000 claims description 49
- XOFYZVNMUHMLCC-ZPOLXVRWSA-N prednisone Chemical compound O=C1C=C[C@]2(C)[C@H]3C(=O)C[C@](C)([C@@](CC4)(O)C(=O)CO)[C@@H]4[C@@H]3CCC2=C1 XOFYZVNMUHMLCC-ZPOLXVRWSA-N 0.000 claims description 39
- 125000006850 spacer group Chemical group 0.000 claims description 13
- 238000004364 calculation method Methods 0.000 claims description 8
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 6
- 230000000903 blocking effect Effects 0.000 claims description 6
- 238000002474 experimental method Methods 0.000 claims description 5
- 239000011435 rock Substances 0.000 claims description 4
- 239000004576 sand Substances 0.000 claims description 4
- 238000003756 stirring Methods 0.000 claims description 4
- 239000002245 particle Substances 0.000 claims description 3
- 229920000747 poly(lactic acid) Polymers 0.000 claims description 3
- 239000004626 polylactic acid Substances 0.000 claims description 3
- 239000006004 Quartz sand Substances 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims description 2
- 230000015572 biosynthetic process Effects 0.000 claims 1
- 230000008569 process Effects 0.000 abstract description 5
- 230000009466 transformation Effects 0.000 abstract description 2
- 239000010410 layer Substances 0.000 description 8
- 230000004048 modification Effects 0.000 description 6
- 238000012986 modification Methods 0.000 description 6
- 238000002347 injection Methods 0.000 description 5
- 239000007924 injection Substances 0.000 description 5
- 238000011161 development Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 230000003068 static effect Effects 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000012360 testing method Methods 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
- 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
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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
- E21B43/261—Separate steps of (1) cementing, plugging or consolidating and (2) fracturing or attacking the formation
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B49/00—Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells
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Abstract
The invention discloses a temporary plugging method in a shale oil fracturing artificial crack, which comprises the following steps: determining the height of the artificial crack; determining the temporary plugging thickness in the artificial crack; determining the using amount of the temporary plugging agent in the artificial crack; injecting temporary plugging liquid consisting of temporary plugging agent, active water and propping agent into the artificial fracture at a certain construction displacement to form temporary bridge plugging in the artificial fracture; and controlling the pressure of the temporary bridge plug to enable the reservoir to form a diversion fracture. The invention utilizes the logging data of the shale oil reservoir and sets a temporary plugging bridge in the fracturing (artificial fracture) through a temporary plugging process, thereby forming a diversion fracture in the artificial fracture and realizing the fracturing transformation of the shale oil reservoir.
Description
Technical Field
The invention relates to the field of shale oil exploration and development, in particular to a temporary plugging method in a shale oil fracturing artificial crack.
Background
In recent years, China increases the exploration strength of shale oil reservoirs, and a plurality of oil and gas fields get exploration breakthrough, but the development difficulty is high. Compared with the conventional oil and gas field development, the shale oil reservoir has poor physical property, small fracturing modification volume, low yield and difficult artificial fracture modification.
Disclosure of Invention
The invention aims to solve the problems of small size of fracturing modification and difficulty in manual fracture modification, and aims to provide a temporary blocking method for the inside of a shale oil fracturing manual fracture, so that the problem of manual fracture modification is solved.
A temporary plugging method in a shale oil fracturing artificial crack comprises the following steps:
s1, determining the height of the artificial crack;
s2, determining the temporary plugging thickness in the artificial crack;
s3, determining the using amount of the temporary plugging agent in the artificial crack;
s4, injecting temporary plugging liquid consisting of temporary plugging agent, active water and propping agent at a certain construction displacement to form temporary bridge plugging in the artificial fracture;
and S5, controlling the pressure of the temporary bridge plug to enable the reservoir to form a diversion fracture.
Specifically, the step of confirming the artificial fracture height in step S1 specifically includes the following steps:
a1, confirming stress parameters and rock mechanics parameters of the artificial fracture within a certain range through logging data of a shale oil reservoir;
a2, calculating the upper and lower stress difference delta P and the modulus difference delta E of the Young modulus of the upper and lower interlayer/lower interlayer with the minimum principal stress above/below the artificial crack;
a3, determining the position of an upper interlayer of the artificial fracture and the position of a lower interlayer of the artificial fracture according to the sum of the upper and lower stress differences delta P of the minimum principal stress and the modulus difference delta E of the Young modulus;
and A4, calculating the depth difference between the upper interlayer of the artificial crack and the lower interlayer of the artificial crack, and confirming the height H of the artificial crack.
Preferably, the acquisition range of the logging data in the step a1 is 20m above and below the artificial fracture;
in step a3, the formula for identifying the upper spacer or the lower spacer is: Δ P + Δ E.gtoreq.12.
Specifically, the step S2 of determining the temporary plugging thickness in the artificial fracture seam specifically includes the following steps:
b1, selecting a temporary plugging agent, selecting the average width W of the artificial crack, and performing a simulated indoor temporary plugging experiment;
and B2, determining the temporary blocking thickness L through experimental data, and enabling the temporary bridge block to bear the pressure in the artificial fracture to be not less than the horizontal stress difference in the artificial fracture.
Preferably, in step B1, the temporary plugging agent is degradable polylactic acid particles with a size of 1-3mm, and the average width W of the artificial crack is 0.01 m.
Specifically, the calculation formula for determining the usage amount of the temporary plugging agent in the artificial fracture in step S3 is as follows: the dosage M of the temporary plugging agent is 2A rho HWL;
in the above formula: rho is the density of the temporary plugging agent;
a is the surplus;
h is the height of the artificial crack;
w is the average width of the artificial crack;
and L is the temporary plugging thickness.
Specifically, the steps S4 and S5 specifically include the following steps:
c1, mixing and stirring the temporary plugging agent, the active water and the proppant;
c2, injecting the mixture to a temporary plugging position by a fixed construction displacement to form a temporary bridge plug;
c3, performing pressure analysis, and calculating the pressure rise P1 of the temporary bridge plug under the same displacement;
c4, confirming the horizontal stress difference P2 between the minimum principal stress and the maximum principal stress of the artificial fracture according to the logging data of the shale oil reservoir;
c5, if P1 is less than P2, continuing injecting the temporary plugging liquid until P1 is more than P2;
c6, temporary blocking in the seam is effective, and a diversion crack is formed.
Preferably, the usage amount of the propping agent is 10 percent of the temporary plugging agent, and the construction displacement is 2.0-3.0m3And/min, the propping agent is quartz sand or ceramsite with 40-70 meshes.
Further, after a steering crack is formed, a large-discharge high-concentration sand is injected, and a new oil-gas seepage channel is established.
Compared with the prior art, the method utilizes the logging data of the shale oil reservoir and sets the temporary plugging bridge in the fracturing (artificial fracture) through the temporary plugging process, so that the artificial fracture forms a steering fracture, and the fracturing transformation of the shale oil reservoir is realized.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the principles of the invention.
FIG. 1 is a schematic flow chart of a temporary plugging method in a shale oil fracturing artificial fracture according to the invention.
FIG. 2 is a graph of experimental requirements for temporary plugging thickness for a shale oil fracturing artificial fracture internal temporary plugging method according to the invention.
FIG. 3 is a schematic view of a turning fracture of the method for temporary plugging in an artificial fracture in shale oil fracturing according to the invention.
Reference numerals: 1-shale oil reservoir, 2-artificial fracture, 3-temporary bridge plugging and 4-diversion fracture.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail with reference to the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are for purposes of illustration only and are not to be construed as limitations of the invention.
It should be noted that, for convenience of description, only the portions related to the present invention are shown in the drawings.
In the present invention, the embodiments and features of the embodiments may be combined with each other without conflict. The present invention will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.
A temporary plugging process method in a shale oil fracturing artificial crack 2 seam comprises the following steps:
s1, determining the height of the artificial crack 2;
s2, determining the temporary plugging thickness in the artificial crack 2;
s3, determining the using amount of the temporary plugging agent in the artificial crack 2;
s4, injecting temporary plugging liquid consisting of temporary plugging agent, active water and propping agent at a certain construction displacement to form a temporary bridge plug 3 in the artificial fracture 2;
and S5, controlling the pressure of the temporary bridge plug 3 to enable the reservoir to form a diversion fracture 4.
The temporary plugging agent is injected into the artificial crack 2 (namely fracturing), the temporary plugging agent is used for forming a temporary plugging bridge, oil gas is also plugged in the artificial crack 2 through the temporary plugging bridge, and meanwhile, under the condition that the pressure intensity of the temporary plugging bridge is continuously increased, acting force is applied to an interlayer of a reservoir stratum, and a new crack is pressed open to form a diversion crack 4.
The step of confirming the height of the artificial crack 2 specifically comprises the following steps:
a1, confirming stress parameters and rock mechanics parameters of the artificial fracture 2 within a certain range through logging data of the shale oil reservoir 1;
a2, calculating the upper and lower stress difference delta P and the modulus difference delta E of the Young modulus of the upper and lower interlayer/lower interlayer with the minimum principal stress above/below the artificial crack 2;
a3, determining the position of an upper interlayer of the artificial fracture and the position of a lower interlayer of the artificial fracture according to the sum of the upper and lower stress differences delta P of the minimum principal stress and the modulus difference delta E of the Young modulus;
and A4, calculating the depth difference between the upper interlayer and the lower interlayer of the artificial crack, and confirming the height H of the artificial crack 2.
And determining the interlayer in a certain range above and below the artificial fracture 2 as a test layer according to the logging data.
Setting the depth of the position of the artificial crack 2 as h;
confirming the upper and lower stress difference delta P of the minimum principal stress of the interlayer of the first upper interlayer (the depth h-a, the unit m) and the modulus difference delta E of the Young modulus according to logging data, and calculating the sum of delta P + delta E;
if the sum of delta P and delta E is not more than a set value (as a basis for judging that the artificial crack 2 does not expand any more), continuously confirming the upper and lower stress difference delta P of the minimum principal stress of the interlayer of the second upper interlayer (the depth h-b, the unit m) and the modulus difference delta E of the Young modulus, and calculating the sum of delta P and delta E;
if the sum of delta P and delta E is not more than a set value (as a basis for judging that the artificial crack 2 does not expand any more), continuously confirming the upper and lower stress difference delta P of the minimum principal stress of the interlayer of the third upper interlayer (the depth h-c, unit m) and the modulus difference delta E of the Young modulus, and calculating the sum of delta P and delta E;
……
and the rest is repeated until the interlayer (named as the final upper interlayer) with the sum of the delta P and the delta E larger than the set value is obtained.
Similarly, the final method for confirming the lower interlayer is as follows:
determining the upper and lower stress difference delta P of the minimum principal stress of the interlayer of the first lower interlayer (depth h + a, unit m) and the modulus difference delta E of the Young modulus according to logging data, and calculating the sum of delta P + delta E;
if the sum of delta P and delta E is not more than a set value (as a basis for judging that the artificial crack 2 does not expand any more), continuously confirming the upper and lower stress difference delta P and the modulus difference delta E of the Young modulus of the interlayer with the minimum principal stress of the second lower interlayer (the depth h + b and the unit m), and calculating the sum of delta P and delta E;
if the sum of delta P and delta E is not more than a set value (as a basis for judging that the artificial crack 2 does not expand any more), continuously confirming the upper and lower stress difference delta P and the modulus difference delta E of the Young modulus of the interlayer with the minimum principal stress of the third lower interlayer (the depth h + c and the unit m), and calculating the sum of delta P and delta E;
……
and the rest is repeated until the interlayer (named as the final lower interlayer) with the sum of the delta P and the delta E larger than the set value is obtained.
In the calculation process of the final upper interlayer and the final lower interlayer, a is more than b and less than c … …;
calculating by the formula: the height H of the artificial crack 2 is the depth of the final lower spacer layer-the depth of the final upper spacer layer.
The method for determining the temporary plugging thickness in the artificial crack 2 specifically comprises the following steps:
b1, selecting a temporary plugging agent, selecting the average width W of the artificial fracture 2, and performing a simulated indoor temporary plugging experiment;
and B2, determining the temporary blocking thickness L through experimental data, and enabling the temporary bridge 3 to bear the pressure in the artificial fracture 2 to be not less than the horizontal stress difference in the artificial fracture 2.
The average width of the artificial fractures 2 is obtained according to the prior art, and is generally 0.01m, and may be adjusted to a width suitable for the local geological conditions according to the geological conditions. And the temporary plugging thickness under a certain pressure bearing condition (namely as shown by the abscissa in fig. 2) is obtained through an indoor temporary plugging experiment.
The temporary plugging agent can be selected according to specific conditions, but in order to protect the environment, a degradable material is preferably selected.
The calculation formula for determining the using amount of the temporary plugging agent in the artificial crack 2 is as follows: the dosage M of the temporary plugging agent is 2A rho HWL;
in the above formula: rho is the density of the temporary plugging agent;
a is the surplus;
h is the height of the artificial crack 2;
w is the average width of the artificial crack 2;
and L is the temporary plugging thickness.
In order to avoid the situation that temporary plugging is not complete due to calculation errors, a part of margin is additionally designed when the temporary plugging agent is determined, and if the margin is 10%, A is 1.1; if the margin is 20%, then A is 1.2 … …
Steps S4 and S5 specifically include the following steps:
c1, mixing and stirring the temporary plugging agent, the active water and the proppant;
c2, injecting the temporary bridge plug into the temporary plug position by a fixed construction displacement to form a temporary bridge plug 3;
c3, performing pressure analysis, and calculating the pressure amplitude P1 of the temporary bridge plug 3 under the same displacement;
c4, confirming the horizontal stress difference P2 between the minimum principal stress and the maximum principal stress of the artificial fracture 2 according to the logging data of the shale oil reservoir 1;
c5, if P1 is less than P2, continuing injecting the temporary plugging liquid until P1 is more than P2;
c6, temporary blocking in the seam is effective, and a diversion crack 4 is formed.
The proppant is used for supporting the temporary plugging agent to form solid accumulation in the artificial fracture 2, and can be flexibly selected according to specific conditions.
The using displacement can be selected to be 2.0-3.0m3The/min can be adjusted according to specific conditions, so long as the injection can be carried out, the collapse can be kept, and the effective stacking can be carried out.
Pressure analysis is needed during injection, the pressure amplitude of oil gas in the artificial fracture 2 to the temporary bridge plug 3 is calculated, and if the pressure amplitude does not exceed the horizontal stress difference between the minimum principal stress and the maximum principal stress of the artificial fracture 2, a new fracture (namely, a steering fracture 4) can not be pressed in the artificial fracture 2 at the moment, so that temporary plugging liquid needs to be injected continuously.
However, the pressure fluctuation of the temporary bridge plug 3 exceeds the horizontal stress difference between the minimum principal stress and the maximum principal stress, the injection can be suspended, and a new diversion fracture 4 can be pressed out from the reservoir and extended under the action of static pressure.
After the steering crack 4 is formed, a large-discharge high-concentration sand is injected, and a new oil-gas seepage channel is established. This is a subsequent step, and after a new channel is formed, the relevant oil and gas collection work can be carried out.
For ease of illustration, one embodiment with specific parameters is provided.
Detailed parameters, see in particular the table below;
according to the data in the table, a temporary plugging process method in the shale oil fracturing artificial fracture 2 is explained in detail.
Confirming the height of the artificial crack 2:
confirming stress parameters and rock mechanics parameters within the range of 20m above and below the artificial fracture 2 through logging data of the shale oil reservoir 1;
setting the depth of the position of the artificial crack 2 to be 2230.0-2238.0 m;
according to the numerical simulation result, the sum of the upper and lower stress difference delta P (mechanical difference) and the Young modulus difference delta E (lithology difference) of the minimum upper and lower principal stress of the reservoir reaches 12, and the sum is used as a basis for judging that the artificial fracture 2 does not expand any more, and the calculation (delta P + delta E) does not bring in the units of delta P and delta E.
As in the above table, two specific upper spacers are provided.
Confirming the upper and lower stress difference delta P (2.0MPa) of the minimum principal stress of the interlayer of the first upper interlayer (2224.0m) and the modulus difference delta E (12.5Gpa) of the Young modulus according to logging data, and calculating the sum of delta P + delta E to be more than 12;
confirming the upper and lower stress difference delta P (2.1MPa) of the minimum principal stress of the interlayer of the second upper interlayer (2217.0m) and the modulus difference delta E (11.4Gpa) of the Young modulus according to logging data, and calculating the sum of delta P + delta E to be more than 12;
in this result, the first upper spacer layer (2224.0m) is set as the final upper spacer layer because the first upper spacer layer (Δ P + Δ E > 12).
Similarly, the final method for confirming the lower interlayer is as follows:
confirming the upper and lower stress difference delta P (2.6MPa) of the minimum principal stress of the interlayer of the first lower interlayer (2242.0m) and the modulus difference delta E (5.3Gpa) of the Young modulus according to logging data, and calculating the sum of delta P and delta E to be less than 12;
confirming the upper and lower stress difference delta P (3.8MPa) of the minimum principal stress of the interlayer of the second lower interlayer (2249.8m) and the modulus difference delta E (10.5Gpa) of the Young modulus according to logging data, and calculating the sum of delta P and delta E to be more than 12;
in this result, the second lower spacer layer (2249.8m) was set as the final lower spacer layer because the second lower spacer layer (Δ P + Δ E > 12).
Calculating by the formula: the height H of the artificial crack 2 is equal to the depth of the final lower interlayer-the depth of the final upper interlayer, and H is 2249.8-2224 is equal to 25.8 m.
Determining the temporary plugging thickness in the artificial crack 2:
selecting a temporary plugging agent (degradable polylactic acid particles of 1-3mm are selected), selecting the average width W of the artificial crack 2 to be 0.01m, and carrying out a simulated indoor temporary plugging experiment;
the temporary plugging thickness L is determined through experimental data, and the bearing pressure of the temporary bridge plug 3 in the artificial fracture 2 is not less than the horizontal stress difference in the artificial fracture 2.
The experimental result is shown in fig. 2, the abscissa in fig. 2 is the temporary plugging thickness, the ordinate is the pressure to which the temporary plugging thickness needs to be subjected, and the pressure is the horizontal stress difference between the minimum principal stress and the maximum principal stress of the artificial fracture 2.
In this embodiment, L is 0.248m to meet the requirement that the bearing pressure exceeds 7MPa of the horizontal stress difference.
The calculation formula for determining the using amount of the temporary plugging agent in the artificial crack 2 is as follows: the dosage M of the temporary plugging agent is 2A rho HWL;
in the above formula: rho is the density of the temporary plugging agent;
a is the surplus;
h is the height of the artificial crack 2;
w is the average width of the artificial crack 2;
and L is the temporary plugging thickness.
In order to avoid the situation that temporary plugging is not complete due to calculation errors, a part of margin is additionally designed when the temporary plugging agent is determined, and if the margin is 10%, A is 1.1; if the surplus is 20%, A is 1.2 … …
In this example, the density of the temporary plugging agent was 1.2g/cm3The allowance is 20%, the height of the artificial crack 2 is 25.8m, the average width of the artificial crack 2 is 0.01m, and the temporary plugging thickness is 0.248 m.
The dosage of temporary plugging agent M is 1.2 × 1200 × 2HWL 184 (kg).
Mixing and stirring the temporary plugging agent, the active water and the propping agent, wherein the active water is 20m3The proppant content was 10%.
At 2.0-3.0m3Injecting construction displacement of/min to a temporary plugging position to form a temporary bridge plug 3;
carrying out pressure analysis, and calculating the pressure expansion P1 of the temporary bridge plug 3 under the same displacement;
confirming that the horizontal stress difference P2 between the minimum principal stress and the maximum principal stress of the artificial fracture 2 is 6.8 Mpa;
if P1 is less than P2, continuing to inject the temporary plugging fluid until P1 is more than P2, and opening a new diversion fracture 4 and extending the new diversion fracture in the reservoir by the net pressure to form a diversion artificial fracture 2;
pressure analysis is needed during injection, the pressure amplitude of oil gas in the artificial fracture 2 to the temporary bridge plug 3 is calculated, and if the pressure amplitude does not exceed the horizontal stress difference between the minimum principal stress and the maximum principal stress of the artificial fracture 2, a new fracture (namely, a steering fracture 4) can not be pressed in the artificial fracture 2 at the moment, so that temporary plugging liquid needs to be injected continuously.
However, the pressure fluctuation of the temporary bridge plug 3 exceeds the horizontal stress difference between the minimum principal stress and the maximum principal stress, the injection can be suspended, and a new diversion fracture 4 can be pressed out from the reservoir and extended under the action of static pressure.
The temporary plugging in the crack is effective, a turning crack 4 is formed, the sand is added with high concentration and large discharge amount, and a new oil gas seepage channel is established.
In the description herein, reference to the description of the terms "one embodiment/mode," "some embodiments/modes," "example," "specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment/mode or example is included in at least one embodiment/mode or example of the application. In this specification, the schematic representations of the terms used above are not necessarily intended to be the same embodiment/mode or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments/modes or examples. Furthermore, the various embodiments/aspects or examples and features of the various embodiments/aspects or examples described in this specification can be combined and combined by one skilled in the art without conflicting therewith.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the feature. In the description of the present application, "plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.
It will be understood by those skilled in the art that the foregoing embodiments are merely for clarity of description and are not intended to limit the scope of the invention. It will be apparent to those skilled in the art that other variations or modifications may be made on the above invention and still be within the scope of the invention.
Claims (5)
1. A temporary plugging method in a shale oil fracturing artificial crack is characterized by comprising the following steps:
s1, determining the height of the artificial crack, and specifically comprising the following steps:
a1, confirming stress parameters and rock mechanics parameters of the artificial fracture within a certain range through logging data of a shale oil reservoir;
a2, calculating the upper and lower stress difference delta P and the modulus difference delta E of the Young modulus of the upper and lower interlayer/lower interlayer with the minimum principal stress above/below the artificial crack;
a3, determining the position of an upper interlayer of the artificial fracture and the position of a lower interlayer of the artificial fracture according to the sum of the upper and lower stress differences delta P of the minimum principal stress and the modulus difference delta E of the Young modulus;
a4, calculating the depth difference between an upper interlayer and a lower interlayer of the artificial crack, and confirming the height H of the artificial crack;
s2, determining the temporary plugging thickness in the artificial crack, which comprises the following steps:
b1, selecting a temporary plugging agent, selecting the average width W of the artificial crack, and performing a simulated indoor temporary plugging experiment;
b2, determining the temporary plugging thickness L through experimental data, and enabling the bearing pressure of the temporary bridge plug in the artificial fracture to be not less than the horizontal stress difference in the artificial fracture;
s3, determining the using amount of the temporary plugging agent in the artificial crack, wherein the calculation formula is as follows: the dosage of the temporary plugging agent M =2A rho HWL;
in the above formula: rho is the density of the temporary plugging agent; a is the surplus; h is the height of the artificial crack; w is the average width of the artificial crack; l is the temporary plugging thickness;
s4, injecting temporary plugging liquid consisting of temporary plugging agent, active water and propping agent into the artificial fracture at a certain construction displacement to form temporary bridge plug, and specifically comprising the following steps:
c1, mixing and stirring the temporary plugging agent, the active water and the proppant;
c2, injecting the mixture to a temporary plugging position by a fixed construction displacement to form a temporary bridge plug;
s5, controlling the pressure of the temporary bridge plug to enable the reservoir to form a diversion fracture, and specifically comprising the following steps:
d1, performing pressure analysis, and calculating the pressure rise P1 of the temporary bridge plug under the same displacement;
d2, confirming the horizontal stress difference P2 between the minimum principal stress and the maximum principal stress of the artificial fracture according to the logging data of the shale oil reservoir;
d3, if P1 is less than P2, continuing to inject the temporary plugging liquid until P1 is more than P2;
d4, temporary plugging in the seam is effective, and a turning crack is formed.
2. The method for temporarily blocking the inside of an artificial fracture in shale oil fracturing according to claim 1, wherein the logging data in the step A1 is acquired within the range of 20m above and below the artificial fracture;
in step a3, the formula for identifying the upper spacer or the lower spacer is: Δ P + Δ E.gtoreq.12.
3. The method for temporary plugging in the cracks of an artificial shale oil fracturing fracture as claimed in claim 1, wherein 1-3mm of degradable polylactic acid particles are selected as the temporary plugging agent in the step B1, and the average width W =0.01m of the artificial cracks.
4. The method for temporary plugging in the artificial crack of shale oil fracturing according to claim 1, wherein the using amount of the propping agent is 10% of that of the temporary plugging agent, the construction displacement is 2.0-3.0m for cultivation/min, and the propping agent is 40-70 mesh quartz sand or ceramsite.
5. The method of claim 4, wherein after the formation of the diversion fractures, a large volume of high concentration sand is injected to create a new oil and gas seepage path.
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Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4660415A (en) * | 1984-06-29 | 1987-04-28 | Institut Francais Du Petrole | Method for determining at least one magnitude characteristic of a geological formation |
| CN103788936A (en) * | 2013-11-08 | 2014-05-14 | 东方宝麟科技发展(北京)有限公司 | High-strength temporary blocking agent for oil and gas wells and preparation method and application thereof |
| CN105041287A (en) * | 2015-07-23 | 2015-11-11 | 中国石油天然气股份有限公司 | Fiber temporary plugging steering fracturing method for improving productivity of low-permeability tight sandstone oil and gas well |
| CN106194145A (en) * | 2016-09-27 | 2016-12-07 | 西南石油大学 | A kind of the most stifled multistage degree of depth network acid fracturing method |
| CN106350043A (en) * | 2016-07-22 | 2017-01-25 | 北京斯迪莱铂油气技术有限公司 | Compound temporary plugging agent and compound temporary plugging method used in temporary blocking turnaround fracture |
| CN107090282A (en) * | 2017-05-18 | 2017-08-25 | 北京世纪中星能源技术有限公司 | A kind of mixed type diverting agent and its diverting agent mixture, temporary blocking method and application |
| CN107587867A (en) * | 2017-09-25 | 2018-01-16 | 西南石油大学 | A kind of refracturing process design method for lifting shale seam net complexity |
| CN109372466A (en) * | 2018-10-10 | 2019-02-22 | 中国石油天然气股份有限公司华北油田分公司 | The temporary stifled forward method of liquid-solid-liquid phase state conversion is realized using natural Temperature Field |
| CN109458168A (en) * | 2018-09-12 | 2019-03-12 | 中国石油天然气股份有限公司 | Composite temporary plugging diversion fracturing method for improving productivity of gas well in sandstone reservoir |
| CN110210144A (en) * | 2019-06-05 | 2019-09-06 | 西南石油大学 | A kind of diverting agent promotes the optimum design method of fractured horizontal well crack uniform expansion |
| CN112682016A (en) * | 2019-10-17 | 2021-04-20 | 中国石油化工股份有限公司 | Method for determining cross-stratum fracturing parameters of thin interbed reservoir of oil and gas field and fracturing method |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7380600B2 (en) * | 2004-09-01 | 2008-06-03 | Schlumberger Technology Corporation | Degradable material assisted diversion or isolation |
| WO2017074869A1 (en) * | 2015-10-28 | 2017-05-04 | Halliburton Energy Services, Inc. | Near real-time return-on-fracturing-investment optimization for fracturing shale and tight reservoirs |
-
2021
- 2021-07-09 CN CN202110779928.4A patent/CN113279723B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4660415A (en) * | 1984-06-29 | 1987-04-28 | Institut Francais Du Petrole | Method for determining at least one magnitude characteristic of a geological formation |
| CN103788936A (en) * | 2013-11-08 | 2014-05-14 | 东方宝麟科技发展(北京)有限公司 | High-strength temporary blocking agent for oil and gas wells and preparation method and application thereof |
| CN105041287A (en) * | 2015-07-23 | 2015-11-11 | 中国石油天然气股份有限公司 | Fiber temporary plugging steering fracturing method for improving productivity of low-permeability tight sandstone oil and gas well |
| CN106350043A (en) * | 2016-07-22 | 2017-01-25 | 北京斯迪莱铂油气技术有限公司 | Compound temporary plugging agent and compound temporary plugging method used in temporary blocking turnaround fracture |
| CN106194145A (en) * | 2016-09-27 | 2016-12-07 | 西南石油大学 | A kind of the most stifled multistage degree of depth network acid fracturing method |
| CN107090282A (en) * | 2017-05-18 | 2017-08-25 | 北京世纪中星能源技术有限公司 | A kind of mixed type diverting agent and its diverting agent mixture, temporary blocking method and application |
| CN107587867A (en) * | 2017-09-25 | 2018-01-16 | 西南石油大学 | A kind of refracturing process design method for lifting shale seam net complexity |
| CN109458168A (en) * | 2018-09-12 | 2019-03-12 | 中国石油天然气股份有限公司 | Composite temporary plugging diversion fracturing method for improving productivity of gas well in sandstone reservoir |
| CN109372466A (en) * | 2018-10-10 | 2019-02-22 | 中国石油天然气股份有限公司华北油田分公司 | The temporary stifled forward method of liquid-solid-liquid phase state conversion is realized using natural Temperature Field |
| CN110210144A (en) * | 2019-06-05 | 2019-09-06 | 西南石油大学 | A kind of diverting agent promotes the optimum design method of fractured horizontal well crack uniform expansion |
| CN112682016A (en) * | 2019-10-17 | 2021-04-20 | 中国石油化工股份有限公司 | Method for determining cross-stratum fracturing parameters of thin interbed reservoir of oil and gas field and fracturing method |
Non-Patent Citations (2)
| Title |
|---|
| 夏海帮.页岩气井双暂堵压裂技术研究与现场试验.《石油钻探技术》.2020,第48卷(第03期),90-96. * |
| 彭欢等.页岩复杂裂缝支撑剂铺置实验装置的研制及应用.《钻采工艺》.2020,第43卷4-5+76-80. * |
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