CN105004746A - Visual evaluation method of sealing property of gel in micro-channels of rock - Google Patents
Visual evaluation method of sealing property of gel in micro-channels of rock Download PDFInfo
- Publication number
- CN105004746A CN105004746A CN201510397026.9A CN201510397026A CN105004746A CN 105004746 A CN105004746 A CN 105004746A CN 201510397026 A CN201510397026 A CN 201510397026A CN 105004746 A CN105004746 A CN 105004746A
- Authority
- CN
- China
- Prior art keywords
- gel
- shutoff
- rock core
- rock
- area
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Abstract
The invention relates to a visual evaluation method of the sealing property of gel in micro-channels of a rock, and belongs to the fields of recovery efficiency improvement technologies and experiment hydrodynamics in petroleum engineering. A low field nuclear magnetic resonance imaging technology is adopted to research distribution of the gel in the micro-channels, and a nuclear magnetic resonance imaging technology and a T2 spectrum analysis technology are adopted to directly observe the distribution of the gel in the micro-channels of a porous medium in rock core displacement experiments; the area, the leading edge, the trailing edge, the center and other parameters of the gel can be obtained through extracting gel images according to nuclear magnetic resonance image; and the sealing property of the gel in the rock core is quantitatively characterized through calculating the sealing area ratio and the sealing height ratio of the area. The method allows the sealing feature of the gel in the porous medium to be visually described.
Description
Technical field
The present invention relates to the visual evaluating method of the seal-off effect of a kind of gel in rock microchannel, belong to petroleum engineering and improve recovery efficiency technique and experimental fluid mechanics field.
Background technology
In laboratory, rock core displacement test is a kind of method of generally acknowledged research rock core fluid flow inside, be widely used in the field such as oil development and environmental science, but because rock core has not visible feature, the flowing of fluid in rock core can only carry out indirect expression with pressure and flow two indices, or according to pressure---discharge relation, utilizes method for numerical simulation indirectly to characterize.Low-field nuclear magnetic resonance is development in recent years new and high technology rapidly, has had good application in medical treatment and food service industry.How to make rock core displacement process in laboratory more directly even visual, become the target that petroleum engineering technical field lays siege to and the important process carried out.In petroleum engineering, usually adopt the macropore injecting gel shutoff porous medium, regulate the flow channel injecting liquid, improve sweep area and oil displacement efficiency.But rock core flowing experiment traditional at present can only describe or deduce the flow condition of fluid in rock core inside and Flooding Efficiency by the bulk parameter (such as top hole pressure, inlet pressure, flow velocity etc.) on end or border usually.Rock core is just equivalent to a black box for researcher, accurately cannot understand the fluid motion conditions of its inside.
Summary of the invention
The difficult problem characterized is difficult to for the seal-off effect of current gel in rock core, the object of this invention is to provide the visual evaluating method of the seal-off effect of a kind of gel in rock microchannel, rock core flowing experiment and magnetic resonance detection technology are combined, makes the shutoff feature of gel in porous medium obtain describing more intuitively.
For achieving the above object, the present invention adopts following technical scheme:
A visual evaluating method for the seal-off effect of gel in rock microchannel, comprises the steps:
(1) open nuclear magnetic resonance equipment, after the rock core of saturation water is put into magnet, by NMR imaging determination rock core position, make it be in magnetic field center; The slice thickness of rock core sagittal plane and xsect, slice spacings and slice position are arranged, utilizes low-field nuclear magnetic resonance equipment to obtain rock microchannel inner fluid signal in rock core displacement test.
(2) gray level image extracts.Gray level image is by bright dark sign rock core inner diverse location place signal power (signal is more strong brighter, and signal is more weak darker).
(3) area-of-interest (ROI) extracts.Nuclear-magnetism image pick-up signal form is the form of 100mm × 100mm, and rock core sagittal plane is the rectangle of 90mm × 25mm, and xsect is the circle of diameter 25mm, so need the effective coverage of extracting gray level image.
(4) unified mapping.Often open nuclear magnetic resonance gray level image secretly bright according to the display of its own signal power, for the signal in more different picture is strong and weak, the nuclear magnetic resonance picture of same section must be carried out bright showing slinkingly according to unified standard and show.
(5) rock core skeleton is extracted.For determining the skeleton structure of rock core, binary conversion treatment being carried out to the nuclear-magnetism image of saturated core, being separated rock core skeleton and fluid information.
(6) pseudo-coloured silk is added.To gray scale rock core after reunification, add JET pseudo-color, make the differentiation of gel and water more obvious.
(7) gel images is extracted.Extract gel images according to nuclear magnetic resonance image, obtain the parameters such as gel area, gel leading edge, gel trailing edge and gel center.
(8) gel shutoff aspect ratio characterizes: the water of the certain volume of voids of displacement, after water drive, gel shutoff in the vertical height and the ratio of the solidifying rear gel shutoff in the vertical height of time are as gel shutoff aspect ratio, first calculate each sagittal shutoff aspect ratio, then average and be designated as the shutoff aspect ratio of gel in whole rock core:
In formula: r
1for the depth of section of rock core, mm; r
2for gel shutoff height, mm; F
1for shutoff aspect ratio, dimensionless.
(9) gel shutoff area ratio characterizes: in step (8), simultaneously using the ratio of gel after water drive gel area and the hole total area in the horizontal as gel shutoff area ratio; First calculate the shutoff area ratio of each transversal section, then average and be designated as the shutoff area ratio of gel in whole rock core:
In formula: S
1for the area of section of rock core, mm
2; S
2for gel shutoff area, mm
2; F
2for shutoff area ratio, dimensionless.
(10) weighed the change of gel seal-off effect by shutoff aspect ratio and shutoff area ratio: shutoff aspect ratio and shutoff area ratio larger, illustrate that gel seal-off effect is stronger; Shutoff aspect ratio and shutoff area ratio less, illustrate that gel seal-off effect is poorer.
The range of size diameter 25mm of described rock core, length 60mm ~ 180mm.
Described core permeability scope 500mD ~ 5000mD.
The pressure limit of displacement in described step 8) is 0.01MPa ~ 20MPa.
The fluctuations in discharge scope of displacement in described step 8) is 0.1ml/min ~ 5ml/min.
Compared with prior art, the present invention has following outstanding substantive distinguishing features and significant advantage:
The present invention adopts low-field nuclear magnetic resonance imaging technique to study gel seal-off effect in microchannel and characterizes, and rock core flowing experiment and magnetic resonance detection technology is combined, makes the shutoff feature of gel in porous medium obtain describing more intuitively.
Accompanying drawing explanation
Fig. 1 is gel shutoff aspect ratio schematic diagram.
Fig. 2 is gel shutoff area ratio schematic diagram.
Fig. 3 is gel sagittal plane nuclear-magnetism distributed image in rock core.
Fig. 4 is gel xsect nuclear-magnetism distributed image in rock core.
Fig. 5 is gel shutoff aspect ratio characterization result.
Fig. 6 is gel shutoff area ratio characterization result.
Fig. 7 is gel character parameter list.
Embodiment
After now the present invention's specific embodiment being by reference to the accompanying drawings described in.
The visual evaluating method of the seal-off effect of a kind of gel in rock microchannel of the present embodiment, testing procedure is:
(1) open nuclear magnetic resonance equipment, after the rock core of saturation water is put into magnet, by NMR imaging determination rock core position, make it be in magnetic field center; To rock core sagittal plane and xsect slice thickness is set to 0.7cm, slice spacings is set to 0.1cm and slice position is arranged, utilize low-field nuclear magnetic resonance equipment to obtain rock microchannel inner fluid signal in rock core displacement test;
(2) gray level image extracts.The gray level image of gel in rock core is extracted by nuclear magnetic resonance.
(3) area-of-interest (ROI) extracts.The rectangle extracting 90mm × 25mm is the effective coverage of gray level image.
(4) unified mapping.The unified scope mapped of all sagittal plane is 1 ~ 100000 zero dimension equivalent luminance unit.
(5) rock core skeleton is extracted.Carry out binary conversion treatment to the nuclear-magnetism image of saturated core, definition rock core skeleton is 15000 zero dimension equivalent luminance units with the threshold values that is separated of fluid.
(6) add pseudo-coloured silk: to gray scale rock core after reunification, add JET pseudo-color, make the differentiation of gel and water more obvious.
(7) gel images is extracted.Extract gel images according to nuclear magnetic resonance image, extract and the results are shown in Figure 3 and Fig. 4.Obtain the parameters such as gel area, gel leading edge, gel trailing edge and gel center.Extraction the results are shown in Figure 7.
(8) gel shutoff aspect ratio characterizes: the water of the certain volume of voids of displacement, after water drive, gel shutoff in the vertical height and the ratio of the solidifying rear gel shutoff in the vertical height of time are as gel shutoff aspect ratio, as shown in Figure 1, first each sagittal shutoff aspect ratio is calculated, then average and be designated as the shutoff aspect ratio of gel in whole rock core, and result of calculation is drawn, mapping result is shown in Fig. 5:
In formula: r
1for the depth of section of rock core, mm; r
2for gel shutoff height, mm; F
1for shutoff aspect ratio, dimensionless.
(9) gel shutoff area ratio characterizes: in previous step, using the ratio of gel after water drive gel area and the hole total area in the horizontal as gel shutoff area ratio, as shown in Figure 2, first the shutoff area ratio of each transversal section is calculated, then average and be designated as the shutoff area ratio of gel in whole rock core, and result of calculation is drawn, mapping result is shown in Fig. 6:
In formula: S
1for the area of section of rock core, mm
2; S
2for gel shutoff area, mm
2; F
2for shutoff area ratio, dimensionless.
(10) by the sign of shutoff aspect ratio and shutoff area ratio, gel shutoff aspect ratio change in migration process can be obtained little, reduce gradually after shutoff area ratio is first constant.
Claims (5)
1. a visual evaluating method for the seal-off effect of gel in rock microchannel, is characterized in that, comprise the steps:
1) open nuclear magnetic resonance equipment, after the rock core of saturation water is put into magnet, by NMR imaging determination rock core position, make it be in magnetic field center; The slice thickness of rock core sagittal plane and xsect, slice spacings and slice position are arranged, utilizes low-field nuclear magnetic resonance equipment to obtain rock microchannel inner fluid signal in rock core displacement test;
2) gray level image extracts: gray level image is strong and weak by bright dark sign rock core inner diverse location place fluid signal, and signal is more strong brighter, and signal is more weak darker;
3) region of interesting extraction: the effective coverage of extracting gray level image at nuclear-magnetism image pick-up signal form, wherein nuclear-magnetism image pick-up signal form is the form of 100mm × 100mm, wherein rock core sagittal plane is the rectangle of 90mm × 25mm, and xsect is the circle of diameter 25mm;
4) unified mapping: the nuclear magnetic resonance picture of same section carries out bright showing slinkingly according to unified standard and shows;
5) extract rock core skeleton: binary conversion treatment is carried out to the nuclear-magnetism image of saturated core, be separated rock core skeleton and fluid information, determine the skeleton structure of rock core;
6) add pseudo-coloured silk: to gray scale rock core after reunification, add JET pseudo-color, make the differentiation of gel and water more obvious;
7) extract gel images: extract gel images according to nuclear magnetic resonance image, obtain gel area, gel leading edge, gel trailing edge and gel center parameter;
8) gel shutoff aspect ratio characterizes: the water of the certain volume of voids of displacement, after water drive, gel shutoff in the vertical height and the ratio of the solidifying rear gel shutoff in the vertical height of time are as gel shutoff aspect ratio, first calculate each sagittal shutoff aspect ratio, then average and be designated as the shutoff aspect ratio of gel in whole rock core:
In formula: r
1for the depth of section of rock core, mm; r
2for gel shutoff height, mm; F
1for shutoff aspect ratio, dimensionless;
9) gel shutoff area ratio characterizes: the water of the certain volume of voids of displacement, and after water drive, the ratio of gel gel area and the hole total area is in the horizontal as gel shutoff area ratio; First calculate the shutoff area ratio of each transversal section, then average and be designated as the shutoff area ratio of gel in whole rock core:
In formula: S
1for the area of section of rock core, mm
2; S
2for gel shutoff area, mm
2; F
2for shutoff area ratio, dimensionless;
10) weighed the change of gel seal-off effect by shutoff aspect ratio and shutoff area ratio: shutoff aspect ratio and shutoff area ratio larger, illustrate that gel seal-off effect is stronger; Shutoff aspect ratio and shutoff area ratio less, illustrate that gel seal-off effect is poorer.
2. the visual evaluating method of the seal-off effect of gel according to claim 1 in rock microchannel, is characterized in that, the range of size diameter 25mm of described rock core, length 60mm ~ 180mm.
3. the visual evaluating method of the seal-off effect of gel according to claim 1 in rock microchannel, is characterized in that, described core permeability scope 500mD ~ 5000mD.
4. the visual evaluating method of the seal-off effect of gel according to claim 1 in rock microchannel, is characterized in that, the pressure limit of displacement in described step 8) is 0.01MPa ~ 20MPa.
5. the visual evaluating method of the seal-off effect of gel according to claim 1 in rock microchannel, is characterized in that, the fluctuations in discharge scope of displacement in described step 8) is 0.1ml/min ~ 5ml/min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510397026.9A CN105004746B (en) | 2015-07-08 | 2015-07-08 | A kind of visual evaluating method of seal-off effect of the gel in rock microchannel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510397026.9A CN105004746B (en) | 2015-07-08 | 2015-07-08 | A kind of visual evaluating method of seal-off effect of the gel in rock microchannel |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105004746A true CN105004746A (en) | 2015-10-28 |
| CN105004746B CN105004746B (en) | 2017-07-25 |
Family
ID=54377499
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510397026.9A Active CN105004746B (en) | 2015-07-08 | 2015-07-08 | A kind of visual evaluating method of seal-off effect of the gel in rock microchannel |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105004746B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111075439A (en) * | 2018-10-19 | 2020-04-28 | 中国石油天然气股份有限公司 | Method, device and storage medium for determining effective thickness of conglomerate reservoir |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5289124A (en) * | 1991-09-20 | 1994-02-22 | Exxon Research And Engineering Company | Permeability determination from NMR relaxation measurements for fluids in porous media |
| WO1998040763A1 (en) * | 1997-03-11 | 1998-09-17 | Conoco Inc. | Prediction of permeability from capillary pressure curves derived with nmr |
| WO2007051915A2 (en) * | 2005-11-02 | 2007-05-10 | Innov-Pro | Device for carrying out magnetic imagery of the part of the subsoil bordering the wall of an oil well |
| CN101458218A (en) * | 2008-12-28 | 2009-06-17 | 大连理工大学 | Carbon dioxide oil-displacing nmr imaging detection device |
| CN103018153A (en) * | 2012-12-25 | 2013-04-03 | 上海大学 | Evaluation method for end part effects of seepage flow field |
| CN103091346A (en) * | 2013-01-18 | 2013-05-08 | 上海大学 | Rock core displacement effect visual evaluation method |
| CN103954639A (en) * | 2014-04-09 | 2014-07-30 | 上海大学 | Method for detecting distribution of gel in micropores |
-
2015
- 2015-07-08 CN CN201510397026.9A patent/CN105004746B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5289124A (en) * | 1991-09-20 | 1994-02-22 | Exxon Research And Engineering Company | Permeability determination from NMR relaxation measurements for fluids in porous media |
| WO1998040763A1 (en) * | 1997-03-11 | 1998-09-17 | Conoco Inc. | Prediction of permeability from capillary pressure curves derived with nmr |
| WO2007051915A2 (en) * | 2005-11-02 | 2007-05-10 | Innov-Pro | Device for carrying out magnetic imagery of the part of the subsoil bordering the wall of an oil well |
| CN101458218A (en) * | 2008-12-28 | 2009-06-17 | 大连理工大学 | Carbon dioxide oil-displacing nmr imaging detection device |
| CN103018153A (en) * | 2012-12-25 | 2013-04-03 | 上海大学 | Evaluation method for end part effects of seepage flow field |
| CN103091346A (en) * | 2013-01-18 | 2013-05-08 | 上海大学 | Rock core displacement effect visual evaluation method |
| CN103954639A (en) * | 2014-04-09 | 2014-07-30 | 上海大学 | Method for detecting distribution of gel in micropores |
Non-Patent Citations (2)
| Title |
|---|
| CHENG YI-CHONG ET AL.: "Visualization study on fluid distribution and end effects in core flow experiments with low-field mri method", 《JOURNAL OF HYDRODYNAMICS》 * |
| 王洪强 等: "核磁共振成像技术在岩石物理实验中的应用", 《测井技术》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111075439A (en) * | 2018-10-19 | 2020-04-28 | 中国石油天然气股份有限公司 | Method, device and storage medium for determining effective thickness of conglomerate reservoir |
| CN111075439B (en) * | 2018-10-19 | 2023-02-10 | 中国石油天然气股份有限公司 | Method, device and storage medium for determining effective thickness of conglomerate reservoir |
Also Published As
| Publication number | Publication date |
|---|---|
| CN105004746B (en) | 2017-07-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105158287A (en) | Visualization evaluation method of transportation property of gel in rock micro-channel | |
| CN103091346B (en) | A kind of visual evaluating method of rock core displacement effect | |
| CN103954639B (en) | Method for detecting distribution of gel in micropores | |
| CN103018153B (en) | Evaluation method for end part effects of seepage flow field | |
| CN104076046B (en) | Remaining oil micro Distribution IMAQ and quantitatively characterizing method in porous media | |
| CN107014721A (en) | A kind of carbon dioxide dry method fracturing fluid solid-carrying performance evaluating apparatus and method | |
| CN107705318B (en) | Turbulent boundary layer flow field velocity measurement method based on boundary tracing | |
| CN107192811B (en) | A kind of latent erosion visual measuring device of the level of large deformation totally-enclosed | |
| CN104751473B (en) | The determination method and device of the multiple dimensioned Porous Characteristic of carbonatite | |
| CN104535475A (en) | Carbonate rock microstructure determination method and device | |
| CN205620284U (en) | Rainfall simulation is to slope stability's analyzed experiment device | |
| CN103558041B (en) | Measure model test apparatus and the test method of land movement under in-situ stress field action | |
| CN106769771B (en) | A kind of measurement method of the unsaturated soil infiltration coefficient based on low-field nuclear magnetic resonance technology | |
| CN105004639A (en) | Visual evaluation method of diffusivity of gel in micro-channels of rock | |
| CN106769198B (en) | A kind of vertical suspended load sampling apparatus in river | |
| Mohmmed et al. | Measurements of translational slug velocity and slug length using an image processing technique | |
| CN103983551B (en) | Two-dimensional visual seepage experiment device for simulating homogeneity in layer and experiment method thereof | |
| CN106706492A (en) | Penetration device for researching porous medium whole-zone penetration mechanism | |
| CN103616321A (en) | X-ray CT (Computed Tomography) measurement system for gas-water relative permeability | |
| CN207073409U (en) | A kind of gas reservoir inhomogeneous plane water enchroachment (invasion) analogue experiment installation | |
| CN203965255U (en) | Metering-type hydrostatic pressure pilot system | |
| CN105021505A (en) | Visualization evaluation method of retention of gel in rock microchannel | |
| CN105004746A (en) | Visual evaluation method of sealing property of gel in micro-channels of rock | |
| CN107860694A (en) | The method for measuring pre-crosslinked gel particle migration rule in rock micro throat | |
| CN205280545U (en) | Seepage tests sand post or earth pillar suitable for nuclear magnetic resonance analysis and imaging system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |