Core for measuring sand control and sand suppression effect and manufacturing method thereof

Abstract

The application discloses a kind of core for measuring sand prevention and sand suppression effect and manufacturing method, belong to oil and gas field development technical field.Core includes shell and inner core filled in the inside of shell;The shell is the hollow cylindrical shell with one end sealed and the other end opened;The opening of the shell is provided with consolidation part;The consolidation part is composed of epoxy resin, curing agent and sand particle.To solve the technical problems that the cementation degree of rock and sand particle cannot be observed, it is difficult to restore the cementation process of bottom sand particle and the cementation degree of rock formation, and the recovery rate cannot be effectively improved in the prior art.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas field development technology, specifically relating to a core sample for measuring sand control and sand suppression effects and its manufacturing method. Background Technology

[0002] Existing loose sandstone reservoirs account for a considerable proportion of the total oilfield reserves. However, loose and weakly consolidated sandstone formations suffer from severe sand production and poor rock cementation. Their loose structure and low strength lead to reduced extraction rates and affect the oilfield's production efficiency.

[0003] Macro-level geological exploration and development techniques are no longer sufficient to meet the needs of more refined reservoir evaluation and exploitation. Therefore, relevant physical simulations are required in the laboratory to further optimize construction parameters and guide on-site production. Currently, the artificial cores prepared in the laboratory for sand control and sand suppression testing mainly explore the consolidation of different sand grain types mixed with solidifying agents. The artificial cores prepared by this method can only observe the consolidation of a single sand grain, but cannot simulate and explore the degree of cementation and permeability effects between rocks and sand grains in loose sandstone reservoirs. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the present invention aims to provide a core sample and manufacturing method for measuring the sand control and sand suppression effect, so as to solve the technical problems of the prior art, which is that the test of the degree of cementation between rock and sand grains is not observable, it is difficult to restore the consolidation process of the bottom sand grains and the degree of cementation with the rock strata, and it cannot effectively improve the mining rate.

[0005] To achieve the above objectives, the present invention employs the following technical solution:

[0006] This invention provides a core sample for measuring the sand control and sand suppression effect, comprising a shell and an inner core filled inside the shell; the shell is a hollow cylindrical shell with one end sealed and the other end open; a consolidation portion is provided at the opening of the shell; the consolidation portion is composed of epoxy resin, curing agent and sand particles.

[0007] In the specific implementation process, the outer diameter of the hollow cylindrical shell is 2.5cm, and the difference between the inner diameter and the outer diameter of the hollow cylindrical shell does not exceed 0.5cm.

[0008] In practice, the inner core is composed of sand particles.

[0009] In the specific implementation process, the sand particles are quartz particles of 60-120 mesh.

[0010] In the specific implementation process, the mass ratio of the epoxy resin to the curing agent is (40-50):1.

[0011] In practice, the shell is a mortar-like shell that is completely wetted and cannot flow.

[0012] In practice, the mortar-like shell is formed by mixing cement and water.

[0013] This invention also provides a method for manufacturing a rock core for measuring the sand control and sand suppression effect, comprising the following steps:

[0014] S1: Mix cement and water to form a thoroughly moistened, non-flowing mortar, and prepare a hollow cylindrical shell with one end sealed.

[0015] S2: After filling the inner core into the shell, epoxy resin and curing agent with a mass ratio of (40-50):1 are mixed with sand particles at the opening of the shell and then solidified at 60-80℃ to obtain a core for measuring the sand control and sand suppression effect.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] This invention provides a core sample for measuring the sand control and sand suppression effect. Since the main reservoir space in oil reservoirs is fractures and caverns, it is also necessary to consider the degree of cementation between sand particles and fractured rock layers or karst while consolidating sand columns. Therefore, this invention combines the consolidation of rock layers and sand particles, highly reducing the required consolidation status of sand particles in the rock layers of oil and gas well formations. This makes the evaluation process more realistic and visible, and can effectively evaluate the performance of the prepared sand-fixing agent and the degree of cementation between sand particles and rocks, effectively ensuring the sand control and sand suppression effect after sand particle consolidation, making the evaluation process more realistic.

[0018] The sand particles cemented to the rock wall described in this invention can be used to measure the sand control and sand suppression effect of the rock core. It is inexpensive, simple in structure, and easy to manufacture. It can effectively demonstrate the sand control and sand suppression effect of the prepared artificial rock core. It requires less material in the evaluation process and can effectively evaluate the sand control and sand suppression performance of the rock core under different effects. It has strong practicality and reduces experimental costs. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a special rock core used for measuring the sand control and sand suppression effect in Embodiment 1 of the present invention;

[0020] Figure 2 This is a permeability test diagram of a special rock core used to measure the sand control and sand suppression effect in Embodiment 1 of the present invention.

[0021] Wherein: 1-shell; 2-inner core. Detailed Implementation

[0022] To enable those skilled in the art to understand the features and effects of the present invention, the terms and expressions used in the specification and claims are explained and defined in general below. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meaning understood by those skilled in the art regarding the present invention, and in case of conflict, the definitions in this specification shall prevail.

[0023] The theories or mechanisms described and disclosed herein, whether right or wrong, should not in any way limit the scope of the invention, that is, the contents of the invention can be implemented without being limited by any particular theory or mechanism.

[0024] In this document, all features defined by numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are for the sake of brevity and convenience only. Accordingly, descriptions of numerical ranges or percentage ranges should be considered as covering and specifically disclosing all possible sub-ranges and individual numerical values ​​(including integers and fractions) within those ranges.

[0025] In this article, unless otherwise specified, “contains,” “includes,” “containing,” “has,” or similar terms cover the meanings of “composed of” and “mainly composed of,” for example, “A contains a” covers the meanings of “A contains a and others” and “A contains only a.”

[0026] For the sake of brevity, not all possible combinations of the technical features in each implementation scheme or embodiment are described herein. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each implementation scheme or embodiment can be combined arbitrarily, and all possible combinations should be considered within the scope of this specification.

[0027] This invention provides a core sample for measuring the sand control and sand suppression effect and its manufacturing method.

[0028] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0029] The following examples use instruments and equipment conventional in the art. Experimental methods in the following examples, unless otherwise specified, are generally performed under conventional conditions or as recommended by the manufacturer. All raw materials used in the following examples are conventional commercially available products with specifications conventional in the art. In this specification and the following examples, unless otherwise specified, "%" refers to weight percentage, "parts" refers to parts by weight, and "ratio" refers to weight proportion.

[0030] This invention provides a method for manufacturing a rock core for measuring its sand control and sand suppression effect, comprising the following steps:

[0031] 1) Mix cement and water evenly to form a mortar that is thoroughly wetted but not flowing, and prepare a hollow cylindrical shell 1 with one end sealed.

[0032] 2) After filling the entire shell 1 with the inner core 2 composed of sand grains, add epoxy resin and curing agent from the opening at a mass ratio of (40-50):1 and mix them completely with the sand grains. After standing for 6-8 hours, solidify at 60-80℃ to obtain a special rock core that can be used to measure the sand control and sand suppression effect by cementing the sand grains with the rock wall.

[0033] In step one, the outer diameter of the hollow cylindrical shell 1 is 2.5cm, and the difference between the inner and outer diameters of the hollow cylindrical shell does not exceed 0.5cm, that is, the difference between the inner and outer diameters of the hollow cylindrical shell is less than or equal to 0.5cm.

[0034] In step two, the mass ratio of epoxy resin to curing agent is (40-50):1; the sand particles are quartz particles of 60-120 mesh.

[0035] This invention also provides a core sample for measuring the sand control and sand suppression effect, such as... Figure 1 The schematic diagram of the special core shown shows that the outer layer of the core is a shell 1 made of cement mixture, and the inner layer is an inner core 2 composed of sand particles. The core includes the shell 1 and the inner core 2 filled inside the shell 1. The shell 1 is a hollow cylindrical shell with one end sealed and the other end open. A solidification part is provided at the opening of the shell 1. The solidification part is composed of epoxy resin, curing agent and sand particles in a mass ratio of (40~50):1.

[0036] The outer diameter of shell 1 is 2.5cm, and the difference between the inner diameter and the outer diameter of shell 1 is less than or equal to 0.5cm; the sand particles are quartz particles of 60-120 mesh; shell 1 is a mortar-like shell that is completely wetted and cannot flow.

[0037] Example 1

[0038] Cement and water are mixed evenly to form a thoroughly wetted but non-flowing mortar, which is used to prepare a hollow cylindrical shell with an outer diameter of 2.5 cm and an inner and outer diameter difference of 0.5 cm, sealed at one end. After filling the entire shell with sand, 4 g of epoxy resin and 0.1 g of curing agent are mixed and added through the opening to mix completely with the sand. After standing for 6 hours, the mixture is solidified at 60°C to obtain a special rock core that is cemented to the rock wall and can be used to measure the sand control and sand suppression effect.

[0039] Example 2

[0040] Cement and water are mixed evenly to form a thoroughly wetted but non-flowing mortar, which is used to prepare a hollow cylindrical shell with an outer diameter of 2.5 cm and an inner and outer diameter difference of 0.4 cm, sealed at one end. After filling the entire shell with sand, 4.5 g of epoxy resin and 0.1 g of curing agent are mixed and added through the opening to mix completely with the sand. After standing for 7 hours, the mixture is solidified at 70°C to obtain a special rock core that is cemented to the rock wall and can be used to measure the sand control and sand suppression effect.

[0041] Example 3

[0042] Cement and water are mixed evenly to form a thoroughly wetted but non-flowing mortar, which is used to prepare a hollow cylindrical shell with an outer diameter of 2.5 cm and an inner and outer diameter difference of 0.3 cm, sealed at one end. After filling the entire shell with sand, 4.8 g of epoxy resin and 0.1 g of curing agent are mixed and added through the opening to mix completely with the sand. After standing for 7 hours, the mixture is solidified at 80°C to obtain a special rock core that is cemented to the rock wall and can be used to measure the sand control and sand suppression effect.

[0043] Example 4

[0044] Cement and water are mixed evenly to form a thoroughly wetted but non-flowing mortar, which is used to prepare a hollow cylindrical shell with an outer diameter of 2.5 cm and an inner and outer diameter difference of 0.2 cm, sealed at one end. After filling the entire shell with sand, 5 g of epoxy resin and 0.1 g of curing agent are mixed and added through the opening to mix completely with the sand. After standing for 8 hours, the mixture is solidified at 80°C to obtain a special rock core that is cemented to the rock wall and can be used to measure the sand control and sand suppression effect.

[0045] To characterize the permeability performance of the prepared core for measuring sand control and sand suppression effects, the permeability of the core described in Example 1 was tested. The permeability of the core increased from 2.4 mD to 3.5 mD in 100 min and then stabilized, which fully demonstrates the excellent performance of the core for measuring sand control and sand suppression effects.

[0046] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A core sample for measuring the sand control and sand suppression effect, characterized in that, The device includes a shell (1) and an inner core (2) filled inside the shell (1); the shell (1) is a hollow cylindrical shell with one end sealed and the other end open; a solidified part is provided at the opening of the shell (1); the solidified part is composed of epoxy resin, curing agent and sand particles; the inner core (2) is composed of sand particles; the sand particles are quartz particles of 60~120 mesh; the mass ratio of epoxy resin and curing agent is (40~50):1; the shell (1) is a mortar-like shell that is completely wetted and cannot flow; the mortar-like shell is formed by mixing cement and water.

2. The core sample for measuring sand control and sand suppression effects according to claim 1, characterized in that, The outer diameter of the hollow cylindrical shell is 2.5 cm, and the difference between the inner diameter and the outer diameter of the hollow cylindrical shell does not exceed 0.5 cm.

3. A method for manufacturing a rock core for measuring the sand control and sand suppression effect according to any one of claims 1 to 2, characterized in that, Includes the following steps: S1: Mix cement and water to form a mortar that is thoroughly wetted and cannot flow, and prepare a hollow cylindrical shell with one end sealed (1). S2: After filling the inner core (2) inside the shell (1), the epoxy resin and curing agent with a mass ratio of (40~50):1 and the sand particles are mixed completely at the opening of the shell (1) and then solidified at 60~80℃ to obtain a core for measuring the sand control and sand suppression effect. The shell (1) has a solidified part at the opening; the solidified part is composed of epoxy resin, curing agent and sand particles; the inner core (2) is composed of sand particles; the sand particles are quartz particles of 60~120 mesh; the mass ratio of epoxy resin and curing agent is (40~50):1; the shell (1) is a mortar-like shell that is completely wetted and cannot flow; the mortar-like shell is formed by mixing cement and water.

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