Oil reservoir development experiment method

Abstract

The invention belongs to the technical field of oil reservoir development, and discloses an oil reservoir development experiment method, which comprises the following steps: S1, preparing an overlapping area experiment model; s2, preparing an experimental fluid; s3, oil layer water setting is carried out on the superposition area experiment model; s4, carrying out saturated oil treatment on the experimental model in the superposition area; and S5, carrying out a displacement process on the superposed region experimental model. According to the oil reservoir development experiment method, the oil reservoir development process of the superposed areas of the development layers with different lithologies can be simulated, and a theoretical basis is provided for actual oil reservoir development of the superposed areas with different lithologies.

Description

Technical Field

[0001] The invention relates to the technical field of oil reservoir development, and in particular to an oil reservoir development experimental method. Background Art

[0002] Buried hill reservoirs are oil and gas reservoirs that accumulate under the unconformity surface of the formation. After geological exploration, it was found that sandstone directly covered the buried hill without a stable mudstone barrier. In the actual reservoir development process, the oil wells drilled on the sandstone and the reservoir wells drilled on the buried hill are connected to each other, and there is a problem of mutual interference between the two during the development process. There are differences in the underground structure and reservoir properties of different reservoir blocks. The specific methods of reservoir development in the area where sandstone and buried hill overlap and the factors affecting reservoir development need to be studied in detail.

[0003] The above research experiments are generally not conducted directly on the oil field, but are simulated using indoor experiments. Existing research methods generally use numerical simulation methods or use flat plate physical models for experiments. However, existing research methods cannot simulate the connectivity between the production wells opened on the sandstone and the production wells opened in the buried hill, as well as the interference between the two wells. At present, an experimental method is needed to realize the simulation experimental research of oil reservoir development in the superimposed area of ​​sandstone and buried hill.

[0004] Therefore, there is an urgent need for an oil reservoir development experimental method to solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide an oil reservoir development experimental method, which can simulate the oil reservoir development process in the overlapping area of ​​development layers of different lithologies and provide a theoretical basis for the actual oil reservoir development in the overlapping area of ​​different lithologies.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] Reservoir development experimental methods, including:

[0008] Step S1, preparing an overlapping region experimental model;

[0009] Step S2, preparing experimental fluid;

[0010] Step S3, setting the oil layer water in the superimposed area experimental model;

[0011] Step S4, saturating the superimposed area experimental model with oil;

[0012] Step S5: performing a displacement process on the superimposed area experimental model.

[0013] As a preferred solution of the reservoir development experimental method provided by the present invention, in step S1, the following steps are included:

[0014] Step S11, filling the bottom of the simulated inner cavity of the main body of the experimental device with a lower rock layer;

[0015] Step S12, setting a barrier plate on the top of the lower rock layer;

[0016] Step S13, filling the upper rock layer on the interlayer plate, wherein the lithology of the lower rock layer is different from that of the upper rock layer;

[0017] Step S14, setting a first extraction assembly in the lower rock formation, and setting a second extraction assembly in the upper rock formation;

[0018] Step S15, setting an injection component in the simulated inner cavity of the experimental device body;

[0019] Step S16: Install the cover plate to seal the simulated inner cavity.

[0020] As a preferred solution of the reservoir development experimental method provided by the present invention, a plurality of measuring probes are arranged on the cover plate, and the measuring probes are configured to measure the change of oil saturation during the displacement process.

[0021] As a preferred solution of the reservoir development experimental method provided by the present invention, when the barrier plate does not have a permeability function, the injection assembly includes two injection wellbores, and the two injection wellbores are respectively inserted into the lower rock formation and the upper rock formation.

[0022] As a preferred solution of the reservoir development experimental method provided by the present invention, when the barrier plate has a permeability function, the injection assembly includes an injection wellbore, and the injection wellbore is inserted into the upper rock formation.

[0023] As a preferred solution of the reservoir development experimental method provided by the present invention, during the process of step S5, the following steps are also performed:

[0024] Step S51, respectively record the liquid production and water content of the first production component and the second production component.

[0025] As a preferred solution of the reservoir development experimental method provided by the present invention, in step S3, the following steps are included:

[0026] Step S31, injecting water into the side of the overlapping area experimental model using a first constant pressure pump;

[0027] Step S32: Use a second constant pressure pump to inject water into the bottom of the overlapping area experimental model.

[0028] As a preferred embodiment of the reservoir development experimental method provided by the present invention, in step S2, experimental oil and experimental water are prepared.

[0029] As a preferred embodiment of the reservoir development experimental method provided by the present invention, the viscosity of the experimental oil is 0.5 mPa·s, and the salinity of the experimental water is 1000 mg / L.

[0030] As a preferred solution of the reservoir development experimental method provided by the present invention, in step S4, the following steps are included:

[0031] Step S41, performing saturated water treatment on the superimposed area experimental model;

[0032] Step S42: injecting experimental oil into the overlapping area experimental model until it is saturated.

[0033] Beneficial effects of the present invention:

[0034] The oil reservoir development experimental method provided by the present invention first prepares an overlapping area experimental model and experimental fluid to prepare for subsequent experiments. Then, the overlapping area experimental model is set with oil layer water to make the overlapping area experimental model closer to the state of the oil reservoir development area in actual production. The overlapping area experimental model is saturated with oil to create ideal conditions for the subsequent displacement process, which is convenient for monitoring and analyzing the development process using data during the subsequent displacement process. The oil reservoir development experimental method can simulate the overlapping area oil reservoir development process of development layers of different lithologies, and provide a theoretical basis for the actual development of oil reservoirs in overlapping areas of different lithologies. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0036] Figure 1 is a flow chart of the reservoir development experimental method provided in Example 1 of the present invention;

[0037] Figure 2 is a schematic diagram of an oil reservoir development experimental device provided in Example 1 of the present invention;

[0038] Figure 3 is a schematic diagram of a partition provided in Embodiment 1 of the present invention;

[0039] Figure 4 is a schematic diagram of an oil reservoir development experimental device provided in Example 2 of the present invention;

[0040] Figure 5 Schematic diagram of the partition provided in the second embodiment of the present invention Figure 1 ;

[0041] Figure 6 Schematic diagram of the partition provided in the second embodiment of the present invention Figure 2 .

[0042] In the figure:

[0043] 10. Lower rock layer; 20. Upper rock layer;

[0044] 100. Experimental device body;

[0045] 200, partition; 210, seepage hole;

[0046] 310, first extraction component; 320, second extraction component;

[0047] 400, injection assembly; 410, injection wellbore; 420, displacement pump;

[0048] 500, cover plate;

[0049] 610, a first constant pressure pump; 620, a second constant pressure pump. DETAILED DESCRIPTION

[0050] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0051] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0052] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0053] In the description of this embodiment, the terms "upper", "lower", "right", "left" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0054] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0055] Embodiment 1

[0056] This embodiment provides an oil reservoir development experimental device and an oil reservoir development experimental method. The oil reservoir development experimental method is mainly used to conduct experimental research on oil reservoir development in overlapping areas of different lithologies, and uses the oil reservoir development experimental device provided by this embodiment.

[0057] Figure 1 The flowchart of the reservoir development experimental method provided by the first embodiment of the present invention is shown. Figure 1 The reservoir development experimental method provided in this embodiment includes the following steps:

[0058] Step S1, preparing an overlapping region experimental model;

[0059] Step S2, preparing experimental fluid;

[0060] Step S3, setting the oil layer water in the superimposed area experimental model;

[0061] Step S4, saturating the superimposed area experimental model with oil;

[0062] Step S5: performing a displacement process on the superimposed area experimental model.

[0063] Specifically, in step S1, the following steps are included:

[0064] Step S11, filling the lower rock layer 10 at the bottom of the simulated inner cavity of the experimental device body 100;

[0065] Step S12, setting an isolation plate 200 on the top of the lower rock layer 10;

[0066] Step S13, filling the upper rock layer 20 on the interlayer plate 200, wherein the lithology of the lower rock layer 10 is different from that of the upper rock layer 20;

[0067] Step S14, installing a first extraction assembly 310 in the lower rock layer 10, and installing a second extraction assembly 320 in the upper rock layer 20;

[0068] Step S15, setting an injection assembly 400 in the simulated inner cavity of the experimental device body 100;

[0069] Step S16: Install the cover plate 500 to seal the simulated inner cavity.

[0070] Through the above steps, the oil reservoir development experimental device provided in this embodiment is assembled. Figure 2 A schematic diagram showing an oil reservoir development experimental device provided in the first embodiment of the present invention; Figure 3 FIG. 1 is a schematic diagram of a partition provided by Embodiment 1 of the present invention. Figure 2 and Figure 3 In actual situations, there is an interlayer between the sandstone layer and the buried hill, on which a mudstone layer and a weathered leaching layer are distributed. The permeability of the mudstone layer is very low, and the weathered leaching layer is generally permeable. However, in actual situations, there are many layers of weathered leaching layers, so the permeability holes between each layer are staggered, resulting in low permeability of the weathered leaching layer. Therefore, in this embodiment, the partition 200 is set to a flat plate structure, and the partition plate 200 does not have a permeability function. The flat partition 200 divides the simulated inner cavity into an upper cavity and a lower cavity stacked up and down along the height direction of the simulated inner cavity, wherein the upper cavity is used to accommodate the upper rock layer 20, and the lower cavity is used to accommodate the lower rock layer 10.

[0071] Specifically, when the partition plate 200 does not have the permeability function, the injection assembly 400 includes two injection wellbores 410, which are respectively inserted into the lower rock formation 10 and the upper rock formation 20, and the two injection wellbores 410 are respectively used to inject experimental fluid or displacement fluid into the lower rock formation 10 and the upper rock formation 20.

[0072] More specifically, the partition 200 is provided with a plurality of through holes, and a portion of the first production assembly 310, a portion of the second production assembly 320, and two injection wellbores 410 can be respectively installed through the plurality of through holes. The first production assembly 310 includes a first production wellbores, and the second production assembly 320 includes a second production wellbores. The first production wellbores penetrate one through hole and are inserted into the lower rock formation 10; the second production wellbores penetrate another through hole and are inserted into the upper rock formation 20.

[0073] Preferably, in order to avoid the experimental fluid or displacement fluid from seeping out at the connection between the first production wellbore and the partition 200, the connection between the second production wellbore and the partition 200, and the connection between the injection wellbore 410 and the partition 200, in this embodiment, the above-mentioned wellbores and the partition 200 can be set as an integrated structure.

[0074] More specifically, the first production assembly 310 further includes a first receiving structure (not shown), and the first production wellbore is connected to the first receiving structure. The first receiving structure is configured to receive the experimental fluid produced by the first production wellbore. Similarly, the second production assembly further includes a second receiving structure (not shown), and the second production wellbore is connected to the second receiving structure. The second receiving structure is configured to receive the experimental fluid produced by the second production wellbore.

[0075] Preferably, the first receiving structure and the second receiving structure both have a measuring function, and can respectively measure the volume of the experimental fluid produced by the first production wellbore and the second production wellbore. In this embodiment, the first receiving structure and the second receiving structure can use graduated cylinders.

[0076] Optionally, a plurality of measuring probes are provided on the cover plate 500, and the measuring probes are configured to measure the change of oil saturation during the displacement process. The measuring probe is a prior art, and its structure and principle are not described in detail in this embodiment.

[0077] Continue to refer to Figure 2 The reservoir development experimental device is also provided with a pressure unit. The pressure unit includes a first constant pressure pump 610, which is connected to the side of the experimental device body 100, connected to the upper cavity and the lower cavity, and is configured to pump water to the sides of the upper cavity and the lower cavity and maintain a certain pressure to simulate the edge water situation during the actual production process. The pressure unit also includes a second constant pressure pump 620, which is connected to the bottom of the experimental device body 100, connected to the lower cavity, and is configured to pump water to the bottom of the lower cavity and maintain a certain pressure to simulate the bottom water situation during the actual production process.

[0078] Optionally, the lower rock layer 10 may be filled with dolomite, and the upper rock layer 20 may be filled with quartz sand.

[0079] In step S2, experimental oil and experimental water are prepared. In this embodiment, the viscosity of the experimental oil is preferably 0.5 mPa·s, and the mineralization of the experimental water is preferably 1000 mg / L. In other embodiments, the viscosity of the experimental oil and the mineralization of the experimental water can be selected according to actual conditions, and this embodiment is not limited here.

[0080] In step S3, the following steps are included:

[0081] Step S31, using the first constant pressure pump 610 to inject water into the side of the overlapping area experimental model;

[0082] Step S32: Use the second constant pressure pump 620 to inject water into the bottom of the overlapping area experimental model.

[0083] The groundwater in the reservoir that is directly connected to the oil and gas layer is called oil layer water. If the thickness of the oil and gas layer is not large, or the structure is steep, the oil and gas fill the high part of the trap, and the water surrounds the periphery of the oil and gas reservoir, this water is called edge water. Bottom water refers to the water that supports oil and gas at the bottom of the oil and gas layer during oil field production. The oil-water (or gas-water) interface only intersects with the bottom surface of the oil and gas layer. Through the above steps, the edge water and bottom water conditions under actual reservoir development are simulated, making the experimental results closer to the actual situation.

[0084] In step S4, the following steps are included:

[0085] Step S41, performing saturated water treatment on the superimposed area experimental model;

[0086] Step S42: injecting experimental oil into the overlapping area experimental model until it is saturated.

[0087] Through step S41, before injecting the experimental oil into the superimposed area experimental model, first use the displacement pump 420 to perform saturated water treatment, and completely fill the pores in the superimposed area experimental model with experimental water. When the experimental oil is subsequently injected, the produced water volume of the experimental water produced by the first production wellbore and the second production wellbore can be used to know when the superimposed area experimental model achieves the saturated oil state. And calculate the original oil saturation. The original oil saturation refers to the oil saturation of the oil layer in the original state before it is put into production, which is the ratio of the original oil content to the pore volume. The pore volume of the superimposed area experimental model can be converted using the produced volume of the experimental water.

[0088] During the process of step S5, the following steps are also performed:

[0089] Step S51, recording the liquid production and water content of the first production component 310 and the second production component 320 respectively.

[0090] Specifically, during the displacement process, the displacement pump 420 is used to inject displacement fluid into the superimposed area experimental model, and the changes in the liquid production and water content of the first production component 310 and the second production component 320 are recorded in real time, and the change in oil saturation is measured using a measuring probe. The liquid production is the sum of the water production and the oil production.

[0091] Specifically, during the displacement process, the first production component 310 and the second production component 320 are opened at different times, the second production component 320 is opened first to carry out the production process of the upper rock layer 20, and the first production component 310 is opened half an hour later to carry out the production process of the lower rock layer 10. Through the above arrangement, it is possible to first study and record the production process of the upper rock layer 20, and then study and record the production processes of the upper rock layer 20 and the lower rock layer 10 at the same time to form a comparison.

[0092] Embodiment 2

[0093] This embodiment also provides an oil reservoir development experimental device and an oil reservoir development experimental method. Figure 4 A schematic diagram of an oil reservoir development experimental device provided in the second embodiment of the present invention is shown. Figure 5 Schematic diagram of the partition provided by the second embodiment of the present invention Figure 1 . Reference Figure 4 and Figure 5 The difference between this embodiment and the first embodiment is that the partition plate 200 of the oil reservoir development experimental device provided in this embodiment has a permeability function.

[0094] According to the actual distribution of mudstone layer and weathering leaching layer, and according to the principle of geometric similarity, refer to Figure 5 The partition plate 200 has a seepage hole 210, the non-opened portion of the partition plate 200 corresponds to the mudstone layer, and the position of the partition plate 200 with the seepage hole 210 corresponds to the weathering leaching layer. When the partition plate 200 has a permeability function, the injection assembly 400 includes an injection wellbore 410, and the injection wellbore 410 is inserted into the upper rock layer 20.

[0095] Specifically, Figure 6 Schematic diagram of the partition provided by the second embodiment of the present invention Figure 2 . Reference Figure 6 Under actual geological conditions, the seepage effect of the weathered leaching layer is the Darcy seepage of the bedrock and the flow of the fractures. The design is based on the average permeability, but the overall average permeability is low. Therefore, in order to better simulate the seepage channel in the actual reservoir development process, in this embodiment, the seepage flow hole 210 is set to be multiple, the seepage flow hole 210 is circular, and the multiple seepage flow holes 210 are opened according to a certain density. Through the above setting, the seepage flow hole 210 and the surrounding partition 200 can simulate the heterogeneity under geological conditions and achieve a better simulation effect.

[0096] To be more specific, in this embodiment, the injection assembly 400 may be provided with only one injection wellbore 410. When the seepage flow hole 210 is provided on the partition 200, during the saturated water process or displacement process in the experiment, a fluid such as water or displacement fluid can be injected into the upper cavity by using one injection wellbore 410, and the experimental fluid or displacement fluid in the upper cavity can penetrate into the lower cavity under the action of gravity.

[0097] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. An experimental method for reservoir development, characterized in that: include: S1. Prepare an experimental model of the overlapping area; S2, preparing experimental fluid; S3, setting the oil layer water for the superimposed area experimental model; S4, saturating the superimposed area experimental model with oil; S5. Perform displacement process on the superimposed area experimental model.

2. The reservoir development experimental method according to claim 1, characterized in that: In step S1, the following steps are included: S11, filling the bottom of the simulated inner cavity of the experimental device body (100) with a lower rock layer (10); S12, installing an isolation plate (200) on the top of the lower rock layer (10); S13, filling an upper rock layer (20) on the interlayer plate (200), wherein the lithology of the lower rock layer (10) is different from that of the upper rock layer (20); S14, installing a first extraction assembly (310) in the lower rock layer (10), and installing a second extraction assembly (320) in the upper rock layer (20); S15, setting an injection assembly (400) in the simulated inner cavity of the experimental device body (100); S16, installing a cover plate (500) to seal the simulated inner cavity.

3. The reservoir development experimental method according to claim 2, characterized in that: A plurality of measuring probes are arranged on the cover plate (500), and the measuring probes are configured to measure the change of oil saturation during the displacement process.

4. The reservoir development experimental method according to claim 2, characterized in that: When the barrier plate (200) does not have a permeability function, the injection assembly (400) includes two injection wellbores (410), and the two injection wellbores (410) are respectively inserted into the lower rock layer (10) and the upper rock layer (20).

5. The reservoir development experimental method according to claim 2, characterized in that: When the barrier plate (200) has a permeability function, the injection assembly (400) includes an injection wellbore (410), and the injection wellbore (410) is inserted into the upper rock layer (20).

6. The reservoir development experimental method according to claim 2, characterized in that: During the process of step S5, the following steps are also performed: S51. Record the liquid production and water content of the first production component (310) and the second production component (320) respectively.

7. The reservoir development experimental method according to claim 1, characterized in that: In step S3, the following steps are included: S31, injecting water into the side of the stacking area experimental model using a first constant pressure pump (610); S32, using a second constant pressure pump (620) to inject water into the bottom of the overlapping region experimental model.

8. The reservoir development experimental method according to claim 1, characterized in that: In step S2, experimental oil and experimental water are prepared.

9. The reservoir development experimental method according to claim 8, characterized in that: The viscosity of the experimental oil was 0.5 mPa·s, and the mineralization of the experimental water was 1000 mg / L.

10. The reservoir development experimental method according to claim 1, characterized in that: In step S4, the following steps are included: S41, saturating the superimposed area experimental model with water; S42. Inject experimental oil into the superimposed area experimental model until it is saturated.

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