CN108548702B - Preparation blank of matrix-hypertonic strip rock core and rock core preparation method - Google Patents
Preparation blank of matrix-hypertonic strip rock core and rock core preparation method Download PDFInfo
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- CN108548702B CN108548702B CN201810197092.5A CN201810197092A CN108548702B CN 108548702 B CN108548702 B CN 108548702B CN 201810197092 A CN201810197092 A CN 201810197092A CN 108548702 B CN108548702 B CN 108548702B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/286—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q involving mechanical work, e.g. chopping, disintegrating, compacting, homogenising
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/02—Devices for withdrawing samples
- G01N1/04—Devices for withdrawing samples in the solid state, e.g. by cutting
- G01N1/08—Devices for withdrawing samples in the solid state, e.g. by cutting involving an extracting tool, e.g. core bit
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/36—Embedding or analogous mounting of samples
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N2001/2893—Preparing calibration standards
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/36—Embedding or analogous mounting of samples
- G01N2001/366—Moulds; Demoulding
Abstract
A preparation blank body of a matrix-hypertonic strip rock core and a preparation method of the rock core. The main purpose is to provide a blank for preparing a matrix-hypertonic strip core with a matrix part capable of being fully saturated with oil and a preparation method. The method is mainly characterized in that: when preparing a matrix rock high-permeability strip rock core, pressing a matrix and a high-permeability strip part in a pressing mould in a layering and zoning way, pressing two ends of the matrix and the high-permeability strip according to ultra-low permeability, and taking a long rock core with ultra-low permeability at two ends and a matrix-high-permeability strip in the middle when a one-dimensional columnar rock core is cored; when the core holder is saturated with oil, the matrix and the high-permeability strip are both high-pressure saturated areas, so that the simulated oil can smoothly enter the matrix core, the purpose of completely saturating the oil in the matrix core is realized, and whether the matrix core is completely saturated with the oil is judged by adopting a parallel sample. The invention can be used for preparing the matrix of completely saturated oil, namely the columnar one-dimensional core of the high permeability strip, and overcomes the problem that the fully saturated oil cannot be obtained due to the existence of the high permeability strip in the prior art.
Description
Technical Field
The invention relates to a preparation method of a simulated matrix-hypertonic strip core, and belongs to the field of oil and gas field development.
Background
The actual reservoir stratum of the oil field in China forms major channels, high-permeability strips and other advantageous channels through long-term injection development, the level of technical monitoring at present cannot be monitored completely, and can not realize all adjustment, drive and blocking, so that the high-permeability strips exist objectively, the situation of displacing residual oil under the condition of matrix-high-permeability strips is common no matter on a plane or in a longitudinal direction, a conventional columnar one-dimensional columnar core can be prepared at present, the high-permeability strips are arranged in the middle, but the problem of saturated oil occurs in indoor experiment saturated oil, because the permeability of the middle part is high, the saturated oil flows out from the middle part in saturated oil, so that matrix parts on two sides cannot be fully saturated, subsequent experiments cannot be carried out, and matrix-high-permeability strip evaluation research cannot be carried out.
Disclosure of Invention
In order to solve the technical problems mentioned in the background, the present invention provides a new solution. The matrix-hypertonic strip rock core prepared under the solution can realize complete saturated oil, and the specific solution is that when the matrix-hypertonic strip rock core is prepared, a matrix and a hypertonic strip part are pressed in a pressing mould in a layering and zoning mode, the two ends of the matrix and the hypertonic strip are pressed according to ultra-low permeability, when a one-dimensional columnar rock core is cored, a long rock core with ultra-low permeability at the two ends and a matrix-hypertonic strip in the middle is obtained, when the saturated oil is in a rock core holder, because the two ends are ultra-low permeability, the pressure required by the saturated oil is greatly increased, and the matrix and the hypertonic strip part are both high-pressure saturated zones, so that the simulated oil can smoothly enter the matrix rock core, the purpose of completely saturating the matrix rock core with the saturated oil is realized, and whether the matrix rock core with the saturated oil.
The technical scheme of the invention is as follows: the blank for preparing the matrix-hypertonic strip core comprises an upper matrix layer and a lower matrix layer, wherein a hypertonic strip layer is positioned between the upper matrix layer and the lower matrix layer, and the upper matrix layer, the hypertonic strip layer and the lower matrix layer are connected through pressing and gluing to form a matrix, and the blank is characterized in that: the two ends of the matrix are respectively provided with a left-end ultra-low permeation section and a right-end ultra-low permeation section; the matrix is connected with the left-end ultra-low permeability section and the right-end ultra-low permeability section into a whole through pressing and gluing.
The method for preparing the green body and the matrix-hypertonic strip core comprises the following steps:
step oneRespectively pressing a cemented matrix rock core A plate, a homogeneous high-permeability strip rock core B plate and an ultra-low permeability rock core C plate according to the matrix permeability, the high-permeability strip permeability and the thickness condition in a reservoir to be simulated actually and drilling a rock core sample, wherein the ultra-low permeability rock core permeability adopted in the step is 0.1 × 10-3μm2；
Step two: constructing a core fractional pressing structure diagram, determining a material for pressing a heterogeneous matrix-hypertonic strip core D plate according to the core fractional pressing structure diagram, and then averagely dividing the matrix material into 2 parts and correspondingly dividing the ultralow-permeability core material into 3 parts;
step three, installing a bottom plate and a die, and respectively pressing the three layers of cores in the heterogeneous matrix-hypertonic strip core D plate in the step two, wherein the specific steps are as follows:
first layer pressing: dividing the whole die into 3 parts by using a wood board with the length of 200mm and the thickness of 1mm, the width of 50mm at two sides and the width of 100mm in the middle, uniformly loading the 1 st part of the uniformly mixed matrix material obtained in the step two into the middle part of the die, placing the ultralow-permeability core material into the two side parts, removing the thin wood baffle, placing an upper pressing plate above the whole material, slowly pressurizing by using a pressure tester until the pressure is P, and stopping pressurizing;
pressing the second layer: dividing the second layer of materials into 3 parts by using 2 thin baffles, wherein the width of each thin baffle is 50mm, the width of the middle of each thin baffle is 100mm, the material of a high permeability strip is filled in the middle of each thin plate, the mass of the material of the ultra-low permeability core is calculated according to the thickness of the high permeability strip on two sides of each thin plate, the ultra-low permeability core material is uniformly filled in the thin plates, the 2 thin wood baffles are removed, an upper pressing plate is placed above the whole second layer of materials, and the second layer of materials are slowly pressurized to a;
pressing the third layer: and putting 2 thin wood boards in the middle of the core mould again for separation, sequentially adding 2 parts of the matrix material in the middle part, uniformly adding the rest ultra-low permeability residual material to the two sides of the thin wood boards, drawing out the thin wood boards again, adding a pressing plate above the total third material, slowly pressurizing to a pressure P by using a pressure tester, and continuously pressurizing for a time period of T. After the completion, releasing the pressure, taking out the upper pressing plate, and putting the pressed rock core into a thermostat to be cured for 24 hours at the constant temperature of 90 ℃;
step four, core coring is carried out on the solidified heterogeneous matrix-hypertonic strip core D plate in the step three by using a coring bit with the diameter of 25mm and the length of 210mm to form a preparation blank body of the columnar matrix-hypertonic strip core with ultralow-permeability core parts at two sides; selecting 4 matrix-hypertonic strip core preparation blanks with central hypertonic strip positions after coring, wherein the matrix-hypertonic strip core preparation blanks are respectively numbered as D1, D2, D3 and D4;
and step five, calibrating the original oil saturation of the matrix, the high permeability strip and the ultra-low permeability core, wherein the step is realized according to the following path:
respectively placing the columnar samples of the matrix core, the homogeneous high-permeability strip permeability core and the ultra-low permeability core obtained in the step one in a core holder, evacuating, saturating with water and saturating with oil, and calculating the porosity Ø of 3 coresA substrate,ØA strip,ØUltra-lowAnd original oil saturation SAn oi matrix,SAn oi band,Soi ultra lowCalculating the core theoretical porosity Ø of the prepared blanks D1-D4 of the matrix-hypertonic strip cores obtained in the fourth step according to the original oil saturation of the 3 coresTheory of the inventionWith the original oil saturation Soi theory；
Step six, selecting the prepared blank of the matrix-hypertonic strip core obtained in the step four, sequentially putting the prepared blank into a core holder with the length of 200mm, evacuating, calculating the actually measured porosity, selecting the actually measured porosity value and Ø in the step fiveTheory of the inventionThe closest core is prepared for use in step seven;
step seven, placing the prepared blank body of the matrix-high permeability strip rock core selected in the step six into a rock core holder with a corresponding length, setting 10MPa ring pressure, setting back pressure at the outlet end of the holder to be 6MPa, starting inlet pressure from 7MPa, performing an oil-water flooding saturated oil process by adopting a constant pressure pump until the outlet flow rate is stable, gradually increasing the pressure at the injection end to 8MPa and 9MPa in sequence, and calculating the actually-measured oil saturation S of the rock core according to the total water output quantity at the outlet end of the holderThe actual measurement of the oil is carried out,if S isoi actual measurementAnd step five of the inventionoi theoryIf the error is within +/-1%, the saturated oil is considered to be completely saturated, the prepared blank body of the matrix-hypertonic strip core is qualified, and if not, the fourth step to the seventh step are repeatedly executed until the error requirement is met; selecting a matrix-hypertonic strip core blank Dm meeting the complete saturation requirement;
and step eight, cutting two ends of the prepared blank of the fully saturated oil matrix-high permeability strip core, which is preferably selected in the step seven, under a waterless condition, cutting off the ultra-low permeability section, grinding the section, and cleaning the end face to obtain the fully saturated oil matrix-high permeability strip core.
The invention has the following beneficial effects: when the matrix rock hypertonic strip rock core is prepared, the matrix and the hypertonic strip part are pressed in a pressing die in a layering and zoning mode, the two ends of the matrix and the hypertonic strip are pressed according to ultra-low permeability, when the one-dimensional columnar rock core is cored, the long rock core with ultra-low permeability at the two ends and the matrix-hypertonic strip in the middle is obtained, when the rock core holder is filled with saturated oil, because the ultra-low permeability at the two ends, the pressure required by the saturated oil is greatly increased, and the matrix and the hypertonic strip part are both high-pressure saturated zones, so that the simulated oil can smoothly enter the matrix rock core, and the purpose of completely saturating the matrix rock core with. The invention prepares the matrix-hypertonic strip columnar one-dimensional core capable of verifying the completely saturated oil by the design in the core preparation process, clears the obstacles for the technical development in the field, overcomes the problem that the oil cannot be fully saturated due to the existence of the hypertonic strip in the past, and has great significance.
Description of the drawings:
fig. 1 is a schematic diagram of a green body for making a matrix-hypertonic strip core according to the present invention.
Fig. 2 is a diagram of a core partial compression structure according to the present invention.
Fig. 3 is a schematic view of a thin wooden board separating the contents.
Fig. 4 is a matrix-hypertonic strip core after being fully saturated with oil and finally obtained by the method of the invention.
In the figure, 1-a bottom plate 2-an iron peripheral baffle 3-a thin wood plate for separation, 4-an upper matrix layer, 5-a high-permeability strip layer, 6-a lower matrix layer, 7-a right-end ultra-low permeability section, 8-a left-end ultra-low permeability section, 9-a saturated upper matrix layer, 10-a saturated high-permeability strip layer and 11-a saturated lower matrix layer.
The specific implementation mode is as follows:
the invention will be further described with reference to the accompanying drawings in which:
as shown in figure 1, the blank for preparing the matrix-hypertonic strip core comprises an upper matrix layer 4 and a lower matrix layer 6, wherein a hypertonic strip layer 5 is positioned between the upper matrix layer 4 and the lower matrix layer 6, and the upper matrix layer 4, the hypertonic strip layer 5 and the lower matrix layer 6 are connected through pressing and gluing to form a matrix. The unique character lies in: the two ends of the matrix are respectively provided with a left-end ultra-low permeation section 8 and a right-end ultra-low permeation section 7; the matrix is connected with the left-end ultra-low permeability section 8 and the right-end ultra-low permeability section 7 into a whole through pressing and gluing.
The preparation method of the matrix-hypertonic strip core comprises the following steps:
step one, respectively pressing a cemented matrix rock core A plate, a homogeneous high-permeability strip rock core B plate and an ultra-low permeability rock core C plate according to the matrix permeability, the high-permeability strip permeability and the thickness condition in a reservoir to be actually simulated, and drilling a rock core sample, wherein the ultra-low permeability rock core permeability adopted in the step is 0.1 × 10-3μm2。
In the step, according to the matrix permeability, the permeability of a high-permeability strip and the thickness condition of a reservoir to be simulated actually, a rock core pressing die and a pressure tester are used, a quartz sand resin pressing and cementing method is adopted, a die combination with the length of 200mm and the width of 200mm is selected during preparation, and the permeability of the ultra-low permeability rock core is determined to be 0.1 × 10-3μm2，Total core thickness 35mm, determined here to be 0.1 × 10-3The reason for the μm is 0.1 × 10-3μm2Is the lowest permeability lower limit which can be achieved by making the artificial core at present. The quartz sand particle size distribution proportion for preparing the matrix permeability rock core, the high-permeability banded rock core and the ultra-low permeability rock core is respectively obtained by adjusting the quartz sand particle size distribution and the content of the epoxy resin adhesiveAnd the content parameter of the adhesive. Three integral cores of cement A, B, C were then each pressed. A matrix rock core A plate is pressed, cemented and cured, and then a rock core sample is drilled, wherein the diameter of the rock core sample is 25mm, and the length of the rock core sample is 100 mm; homogenizing the rock core B plate with high permeability strips, pressing, cementing, solidifying, and drilling a rock core sample with the diameter of 25mm and the length of 100 mm; and (3) pressing the ultra-low permeability rock core C plate, cementing and curing, and drilling a rock core sample with the diameter of 25mm and the length of 100 mm.
Step two: and constructing a core fractional pressing structure diagram, determining a material for pressing a heterogeneous matrix-hypertonic strip core D plate according to the core fractional pressing structure diagram, and then averagely dividing the matrix material into 2 parts and correspondingly dividing the ultralow-permeability core material into 3 parts.
In this step, because the experimental data obtained in the first step includes the total mass of each material and the thickness data of the pressed core, the total volume of the materials required by the matrix core, the high permeability strip core and the ultra-low permeability core can be calculated according to the design thickness of the constructed core fractional pressed structural chart and the experimental data obtained in the first step, and the quartz sand size distribution proportion and the total sand amount, the total adhesive amount and the curing agent content required according to the parameters listed in the constructed core fractional pressed structural chart are calculated by adopting a volume proportion calculation method. And mixing 3 parts of core material with an adhesive, and then performing sand rubbing and sieving preparation respectively.
Step three, installing a bottom plate and a die, and respectively pressing the three layers of cores in the heterogeneous matrix-hypertonic strip core D plate in the step two, wherein the specific steps are as follows:
first layer pressing: dividing the whole die into 3 parts by using a wood board with the length of 200mm and the thickness of 1mm, the width of 50mm at two sides and the width of 100mm in the middle, uniformly loading the 1 st part of the uniformly mixed matrix material obtained in the step two into the middle part of the die, placing the ultralow-permeability core material into the two side parts, removing the thin wood baffle, placing an upper pressing plate above the whole material, slowly pressurizing by using a pressure tester until the pressure is P, and stopping pressurizing;
pressing the second layer: dividing the second layer of materials into 3 parts by using 2 thin baffles, wherein the width of each thin baffle is 50mm, the width of the middle of each thin baffle is 100mm, the material of a high permeability strip is filled in the middle of each thin plate, the mass of the material of the ultra-low permeability core is calculated according to the thickness of the high permeability strip on two sides of each thin plate, the ultra-low permeability core material is uniformly filled in the thin plates, the 2 thin wood baffles are removed, an upper pressing plate is placed above the whole second layer of materials, and the second layer of materials are slowly pressurized to a;
pressing the third layer: and putting 2 thin wood boards in the middle of the core mould again for separation, sequentially adding 2 parts of the matrix material in the middle part, uniformly adding the rest ultra-low permeability residual material to the two sides of the thin wood boards, drawing out the thin wood boards again, adding a pressing plate above the total third material, slowly pressurizing to a pressure P by using a pressure tester, and continuously pressurizing for a time period of T. After the completion, releasing the pressure, taking out the upper pressing plate, and putting the pressed rock core into a thermostat to be cured for 24 hours at the constant temperature of 90 ℃;
step four, core coring is carried out on the solidified heterogeneous matrix-hypertonic strip core D plate in the step three by using a coring bit with the diameter of 25mm and the length of 210mm to form a preparation blank body of the columnar matrix-hypertonic strip core with ultralow-permeability core parts at two sides; selecting 4 matrix-hypertonic strip core preparation blanks with central hypertonic strip positions after coring, wherein the matrix-hypertonic strip core preparation blanks are respectively numbered as D1, D2, D3 and D4;
and step five, calibrating the original oil saturation of the matrix, the high permeability strip and the ultra-low permeability core, wherein the step is realized according to the following path:
respectively placing the columnar samples of the matrix core, the homogeneous high-permeability strip permeability core and the ultra-low permeability core obtained in the step one in a core holder, evacuating, saturating with water and saturating with oil, and calculating the porosity Ø of 3 coresA substrate,ØA strip,ØUltra-lowAnd original oil saturation SAn oi matrix,SAn oi band,Soi ultra lowCalculating the core theoretical porosity Ø of the prepared blanks D1-D4 of the matrix-hypertonic strip cores obtained in the fourth step according to the original oil saturation of the 3 coresTheory of the inventionWith the original oil saturation Soi theory；
Step six, selecting the prepared blank of the matrix-hypertonic strip core obtained in the step four, and sequentially preparing the blankPutting into a core holder with the length of 200mm, evacuating, calculating the measured porosity, selecting the measured porosity value and Ø in the fifth stepTheory of the inventionThe closest core is prepared for use in step seven;
step seven, placing the prepared blank body of the matrix-high permeability strip rock core selected in the step six into a rock core holder with a corresponding length, setting 10MPa ring pressure, setting back pressure at the outlet end of the holder to be 6MPa, starting inlet pressure from 7MPa, performing an oil-water flooding saturated oil process by adopting a constant pressure pump until the outlet flow rate is stable, gradually increasing the pressure at the injection end to 8MPa and 9MPa in sequence, and calculating the actually-measured oil saturation S of the rock core according to the total water output quantity at the outlet end of the holderThe actual measurement of the oil is carried out,if S isoi actual measurementAnd step five of the inventionoi theoryIf the error is within +/-1%, the saturated oil is considered to be completely saturated, the prepared blank body of the matrix-hypertonic strip core is qualified, and if not, the fourth step to the seventh step are repeatedly executed until the error requirement is met; selecting a matrix-hypertonic strip core blank Dm meeting the complete saturation requirement;
and step eight, cutting two ends of the prepared blank of the fully saturated oil matrix-hypertonic strip rock core which is preferably selected in the step seven under the anhydrous condition, cutting off the ultra-low permeability section, grinding the section, and cleaning the end face, wherein the substrate-hypertonic strip rock core is obtained as shown in fig. 4.
One specific example is given below:
the substrate permeability to be simulated was 500 × 10, depending on the actual block conditions in Daqing oil field-3μm2Hypertonic strip permeability 2200 × 10-3μm2And calculating according to a similarity criterion to obtain a hypertonic strip with the thickness of 3mm in the one-dimensional cylindrical rock core, and preparing the rock core by using a rock core pressing mold and a pressure tester and adopting a quartz sand resin pressing and cementing method.
(1) During preparation, the fixed pressure is 10MPa and the holding pressure time is 5min, a mold combination with the length of 200mm and the width of 200mm is selected, and the permeability of the ultra-low permeability core is determined to be 0.1 × 10-3μm2And the total thickness of the core is 35 mm. By adjusting the particle size distribution of the quartz sand and the content of the epoxy resin adhesive, the quartz sand is obtained respectivelyThe material proportion table for preparing the quartz sand particle size distribution proportion and the adhesive content parameter of the matrix permeability rock core, the high-permeability banded rock core and the ultra-low permeability rock core is shown in table 1: .
Table 1 table for preparing materials for preparing each core
| Coarse sand mesh number (40-70) quality (gram) | Fine sand mesh number (300) quality (gram) | Resin mass (gram) | Curing agent quality (gram) | Corresponding permeability (× 10)-3μm2） | Remarks for note |
| 1358 | 2142 | 412 | 26 | 500 | Substrate |
| 2397 | 1103 | 527 | 33 | 2200 | Hypertonic strip |
| 72 | 3428 | 737 | 47 | 0.1 | Ultra-low permeability |
(2) Preparing a matrix core A plate according to the table 1, pressing, cementing, solidifying, drilling a core sample with the diameter of 25mm and the length of 100 mm;
(3) preparing a homogeneous high permeability strip permeability core B plate according to the table 1, pressing, cementing, curing, and drilling a core sample with the diameter of 25mm and the length of 100 mm;
(4) preparing an ultra-low permeability core C plate according to the table 1, pressing, cementing, solidifying, and drilling a core sample with the diameter of 25mm and the length of 100 mm;
(5) preparing a heterogeneous matrix-hypertonic strip core D plate, which comprises the following steps:
1) and calculating the quartz sand size distribution proportion, the total sand amount, the total adhesive amount and the curing agent content required by the matrix core, the high-permeability strip core and the ultra-low-permeability core according to the data obtained in the table 1. As shown in tables 2 and 3 below:
TABLE 2 heterogeneous core Material proportioning Table
| Coarse sand mesh number (40-70) quality (gram) | Fine sand mesh number (300) quality (gram) | Resin mass (gram) | Curing agent quality (gram) | Corresponding permeability (× 10)-3μm2） | Remarks for note | Gross mass of material (gram) |
| 815 | 1285 | 247 | 16 | 500 | Substrate | 2363 |
| 113 | 52 | 25 | 2 | 2200 | Hypertonic strip | 192 |
| 46 | 2203 | 474 | 30 | 0.1 | Ultra-low permeability | 2753 |
TABLE 3 heterogeneous core parts material distribution table
| Number of layers | Gross mass of material (gram) | First pressing (gram) | Second pressing (gram) | Third pressing (gram) |
| Matrix part | 2363 | 1181.5 | 0 | 1181.5 |
| Hypertonic strip | 192 | 0 | 192 | 0 |
| Ultra-low permeability | 2753 | 1308 (averagely divided into two sides) | 138 | 1308 (averagely divided into two sides) |
2) Installing a bottom plate and a die, and respectively pressing three layers of rock cores, wherein the concrete steps are as follows:
first layer pressing: dividing an integral die into 3 parts by using 2 thin wood boards (the thickness is 1 mm) with the length of 200mm and the thickness of 50mm at two sides and the width of 100mm at the middle, as shown in figure 2, uniformly mixing 1 st 1181.5 g of a substrate material which is well divided, uniformly filling the substrate material into the middle part of the die, putting an ultra-low permeability core material into the two side parts, each part being 654 g, after removing a thin wood baffle, putting an upper pressure plate above the integral material, slowly pressurizing by using a pressure tester until the pressure reaches 10MPa, and stopping pressurizing;
pressing the second layer: dividing the second layer of materials into 3 parts by using 2 thin baffles (the thickness is 1 mm), wherein the width of each thin baffle is 50mm, the width of each thin baffle is 100mm, 192 g of materials of a high permeability strip are filled in the middle of each thin plate, the mass of each material of the ultra-low permeability core is calculated according to the thickness of each high permeability strip on two sides, the ultra-low permeability core materials are carefully and uniformly filled, the 2 thin wood baffles are removed, an upper pressure plate is placed above the whole second layer of materials, and the second layer of materials are slowly pressurized to 10MPa by using a pressure tester and then are stopped;
pressing the third layer: and 2 thin wood plates (with the thickness of 1 mm) are placed in the middle of the core mould again for separation, the position is unchanged, 1181.5 g of the matrix material is sequentially added into the middle part, the rest ultra-low permeability materials are respectively added into 654 g of the two sides of each thin wood plate, the 2 thin wood plates are drawn out again, a pressing plate is added above the total third material, the pressure is slowly increased to 10MPa by using a pressure tester, and then the pressure is continuously increased for 5 min. And after the completion, releasing the pressure, taking out the upper pressing plate, and putting the pressed core preparation blank into a thermostat to be cured for 24 hours at the constant temperature of 90 ℃.
3) Coring the solidified core preparation blank by using a coring bit with the diameter of 25mm and the length of 210mm, selecting 4 core preparation blanks with the middle position of a hypertonic strip after coring for standby, and taking out core preparation blanks with the diameter of 25mm and the length of 200mm, and the numbers of D1, D2, D3 and D4 for standby.
(6) Calibrating the original oil saturation of the matrix, the high permeability strip and the ultra-low permeability core
Respectively placing the columnar samples obtained in the steps (2), (3) and (4) in a core holder, evacuating, saturating with water and saturating with oil, and calculating the porosity Ø of the 3 coresA substrate,ØA strip,ØUltra-lowAnd original oil saturation SAn oi matrix,SAn oi band,Soi ultra lowCalculating the theoretical porosity of Ø of the cores D1-D4 in the first step of the invention based on the original oil saturation of the 3 coresTheory of the inventionSaturated with original oilDegree of neutralization Soi theory. Table 4 is a table of test and calculation results.
TABLE 4 test and calculation results table
| Categories | Substrate | Hypertonic strip | Ultra-low permeability core | Rock core with ultra-low permeability at two ends (theory) |
| Porosity of | ØSubstrate=25.1% | ØStrip tape=32.2% | ØUltra-low=10.4% | ØTheory of the invention=17.8% |
| Original oil saturation | Soi matrix=72.3% | Soi strip=75.4% | Soi ultra low=60.5% | Soi theory=68.9% |
(7) Preparing a blank body from the D1-D4 rock core, sequentially putting the blank body into a rock core holder with the length of 200mm, evacuating, calculating the actual measured porosity, and selecting Ø in the step (6) from a test and calculation result table shown in table 5Theory of the inventionThe closest core was subjected to subsequent saturated oil experiments. The D2 rock cores were preferred for subsequent experiments based on the comparative data.
TABLE 5 actual measurement of porosity of each core
| Categories | Rock core with ultra-low permeability at two ends (theory) | D1 actual measurement | D2 actual measurement | D3 actual measurement | D4 actual measurement |
| Porosity of | ØTheory of the invention=17.8% | 17.1% | 17.7% | 16.8% | 17.0% |
(8) Placing a D2 core preparation blank body in a core holder, setting 10MPa ring pressure, setting the outlet end of the holder to back pressure of 6MPa, starting the inlet pressure from 7MPa, adopting a constant pressure pump to perform the oil-water flooding saturated oil process until the outlet flow rate is stable, gradually increasing the pressure of an injection end to 8MPa and 9MPa in sequence, and calculating the actually-measured oil saturation S of the core according to the total water output quantity of the outlet end of the holderThe actual measurement of the oil is carried out,as shown in table 6.
Table 6 actual measurement of oil saturation in core
| Categories | Rock core with ultra-low permeability at two ends (theory) | D2 actual measurement | Remarks for note |
| Original oil saturation | Soi theory=68.9% | 68.2% | Meet the experimental requirements |
(9) And (3) cutting two ends of the D2 core preparation blank under the anhydrous condition, grinding the section, and cleaning the end face to obtain the fully saturated oil matrix-hypertonic strip core with the diameter of 25mm and the length of 100 mm.
Therefore, the matrix-hypertonic strip columnar one-dimensional core which can be verified to be completely saturated oil is prepared by the design in the core preparation process.
Claims (1)
1. A preparation method of a matrix-hypertonic strip core comprises the following steps:
step one, respectively pressing a cemented matrix rock core A plate, a homogeneous high-permeability strip rock core B plate and an ultra-low permeability rock core C plate according to the matrix permeability, the high-permeability strip permeability and the thickness condition in a reservoir to be actually simulated, and drilling a rock core sample, wherein the ultra-low permeability rock core permeability adopted in the step is 0.1 × 10-3μm2；
Step two: constructing a core fractional pressing structure diagram, determining a material for pressing a heterogeneous matrix-hypertonic strip core D plate according to the core fractional pressing structure diagram, and then averagely dividing the matrix material into 2 parts and correspondingly dividing the ultralow-permeability core material into 3 parts;
step three, installing a bottom plate and a die, and respectively pressing the three layers of cores in the heterogeneous matrix-hypertonic strip core D plate in the step two, wherein the specific steps are as follows:
first layer pressing: dividing the whole die into 3 parts by using two thin wood boards, uniformly loading 1 st part of the uniformly mixed matrix material obtained in the second step into the middle part of the die, placing the ultra-low permeability core material into the two side parts, removing the thin wood baffle, placing an upper pressing plate above the whole material, slowly pressurizing to a pressure P by using a pressure tester, and stopping pressurizing;
pressing the second layer: dividing the whole die into 3 parts by using 2 thin wood boards again, filling materials of a high permeability strip in the middle of each thin wood board, calculating the mass of the materials of the ultra-low permeability core according to the thickness of the high permeability strip on two sides, uniformly filling the materials of the ultra-low permeability core, removing 2 thin wood boards, placing an upper pressing plate above the whole second layer of materials, slowly pressurizing by using a pressure tester until the pressure is P, and stopping pressurizing;
pressing the third layer: putting 2 thin wood boards in the middle of the core mould again for separation, keeping the positions unchanged, sequentially adding 2 parts of matrix material in the middle part, uniformly adding the rest ultra-low permeability residual material to the two sides of the thin wood boards, drawing out the thin wood boards again, adding a pressing plate above the total third material, slowly pressurizing to a pressure P by using a pressure tester, and continuously pressurizing for a time period T; after the completion, releasing the pressure, taking out the upper pressing plate, and putting the pressed rock core into a thermostat to be cured for 24 hours at the constant temperature of 90 ℃;
step four, core coring is carried out on the solidified heterogeneous matrix-hypertonic strip core D plate in the step three by using a coring bit with the diameter of 25mm and the length of 210mm to form a preparation blank body of the columnar matrix-hypertonic strip core with ultralow-permeability core parts at two sides; selecting 4 matrix-hypertonic strip core preparation blanks with central hypertonic strip positions after coring, wherein the matrix-hypertonic strip core preparation blanks are respectively numbered as D1, D2, D3 and D4;
and step five, calibrating the original oil saturation of the matrix, the high permeability strip and the ultra-low permeability core, wherein the step is realized according to the following path:
respectively placing the columnar samples of the matrix core, the homogeneous high-permeability strip permeability core and the ultra-low permeability core obtained in the step one in a core holder, evacuating, saturating with water and saturating with oil, and calculating the porosity of 3 cores
And original oil saturation Soi matrix、Soi strip、Soi ultra low(ii) a Calculating the core theoretical porosity of the prepared blanks D1-D4 of the matrix-hypertonic strip cores obtained in the fourth step according to the original oil saturation of the 3 cores
With the original oil saturation Soi theory；
Step six, selecting the prepared blank of the matrix-hypertonic strip core obtained in the step four, sequentially putting the prepared blank into a core holder with the length of 200mm, evacuating, calculating the actually measured porosity, and selecting the actually measured porosity value and the porosity value obtained in the step five
The closest core is prepared for use in step seven;
step seven, placing the prepared blank body of the matrix-high permeability strip rock core selected in the step six into a rock core holder with a corresponding length, setting 10MPa ring pressure, setting back pressure at the outlet end of the holder to be 6MPa, starting inlet pressure from 7MPa, performing an oil-water flooding saturated oil process by adopting a constant pressure pump until the outlet flow rate is stable, gradually increasing the pressure at the injection end to 8MPa and 9MPa in sequence, and calculating the actually-measured oil saturation S of the rock core according to the total water output quantity at the outlet end of the holderoi actual measurementIf S isoi actual measurementAnd step five of the inventionoi theoryThe error is within +/-1%, the saturated oil is considered to be completely saturated, the prepared blank of the matrix-hypertonic strip core is qualified, and otherwise, the steps are repeatedly executedStep four to step seven until the error requirement is met; selecting a matrix-hypertonic strip core blank Dm meeting the complete saturation requirement;
and step eight, cutting two ends of the prepared blank of the fully saturated oil matrix-high permeability strip core, which is preferably selected in the step seven, under a waterless condition, cutting off the ultra-low permeability section, grinding the section, and cleaning the end face to obtain the fully saturated oil matrix-high permeability strip core.
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| CN113863923B (en) * | 2021-10-18 | 2022-11-01 | 中国石油大学(北京) | Physical simulation experiment method for remaining oil distribution constrained by lake-bottom fan configuration |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008249455A (en) * | 2007-03-30 | 2008-10-16 | Shimadzu Corp | NOx GAS GENERATION DEVICE |
| CN103411804A (en) * | 2013-07-03 | 2013-11-27 | 中国石油天然气股份有限公司 | Heterogeneous cementing core model with high-permeability layer and preparation method thereof |
| CN204827402U (en) * | 2015-07-28 | 2015-12-02 | 中国石油天然气股份有限公司 | Experimental model of displacement of reservoir oil mechanism is transferred in research water drive sandstone oil reservoir deep |
| CN105134147A (en) * | 2015-07-18 | 2015-12-09 | 东北石油大学 | Intrastratal heterogeneous well pattern model capable of realizing quality classification injection and production |
| CN106501493A (en) * | 2016-11-03 | 2017-03-15 | 东北石油大学 | A kind of displacement test heterogeneous body self-constant temperature sandpack column and loading method |
| CN107389396A (en) * | 2017-06-23 | 2017-11-24 | 东北石油大学 | Realize the preparation method and its experimental method of heterogeneous core in the layer that dispensing point is adopted |
-
2018
- 2018-03-10 CN CN201810197092.5A patent/CN108548702B/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008249455A (en) * | 2007-03-30 | 2008-10-16 | Shimadzu Corp | NOx GAS GENERATION DEVICE |
| CN103411804A (en) * | 2013-07-03 | 2013-11-27 | 中国石油天然气股份有限公司 | Heterogeneous cementing core model with high-permeability layer and preparation method thereof |
| CN105134147A (en) * | 2015-07-18 | 2015-12-09 | 东北石油大学 | Intrastratal heterogeneous well pattern model capable of realizing quality classification injection and production |
| CN204827402U (en) * | 2015-07-28 | 2015-12-02 | 中国石油天然气股份有限公司 | Experimental model of displacement of reservoir oil mechanism is transferred in research water drive sandstone oil reservoir deep |
| CN106501493A (en) * | 2016-11-03 | 2017-03-15 | 东北石油大学 | A kind of displacement test heterogeneous body self-constant temperature sandpack column and loading method |
| CN107389396A (en) * | 2017-06-23 | 2017-11-24 | 东北石油大学 | Realize the preparation method and its experimental method of heterogeneous core in the layer that dispensing point is adopted |
Non-Patent Citations (3)
| Title |
|---|
| Experimental Study of Chemical Flooding of Suizhong 36-1 Oilfield;Pi Yanfu 等;《The Open Petroleum Engineering Journal, 2015, 8,》;20151231;第8卷;第392-397页 * |
| 特低渗透油藏渗流理论研究;杨清立 等;《钻采工艺》;20071130;第30卷(第6期);第52-54 * |
| 石英砂环氧树脂胶结人造岩心的技术与应用;皮彦夫;《科学技术与工程》;20101031;第10卷(第28期);第6998-7000页 * |
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