A fracture type oil reservoir communication path testing device and method

Abstract

The present application provides a fracture-type oil reservoir connection path testing device and method, including: a model chamber, in which a fracture-type reservoir model is placed, and the fracture-type reservoir model is formed by stacking and splicing natural dense rocks; a fluid inlet and a fluid outlet are provided on the model chamber; a plurality of temperature and pressure sensors are arranged at different positions of the fracture-type reservoir model; a fluid injection device is connected to the fluid inlet; a fluid metering device is connected to the fluid outlet; and a data acquisition system is electrically connected to the plurality of temperature and pressure sensors, and is used to collect temperature values ​​and pressure values ​​of the plurality of temperature and pressure sensors. The test device of the present application can simulate the connection path of a complex fracture channel, and jointly determine the connection path by using temperature changes and system pressure changes, thereby guiding people to develop fracture-type oil reservoirs and facilitating the improvement of the recovery rate of fracture-type oil reservoirs.

Description

Technical Field

[0001] The present application belongs to the technical field of oil and gas reservoir development, and more specifically, to a fracture-type oil reservoir communication path testing device and method. Background Art

[0002] Fracture reservoirs are an important type of reservoir, but due to the complex internal flow channels, the understanding of the internal connection paths and connectivity of fracture reservoirs greatly restricts the efficient development of this type of reservoir. At present, there have been some physical simulation studies on fractured oil and gas reservoirs, among which most of the models are deterministic channel models such as single slit models in regular glass chambers and parallel slit models. There are fewer complex fracture network models, and there is an even greater lack of physical simulation experiments on the connection paths of complex fracture channels. As a result, people are not clear about the connection paths or dominant connection paths of complex fracture channels, which seriously restricts people's development of fractured reservoirs and is not conducive to improving the recovery rate of fractured reservoirs. Summary of the invention

[0003] The purpose of the present application is to provide a fracture-type oil reservoir communication path testing device and method to solve the technical problem that the physical model of the fracture-type oil and gas reservoir in the prior art is difficult to simulate the communication path of the complex fracture channel.

[0004] To achieve the above-mentioned purpose, in a first aspect of the present application, a fractured reservoir communication path testing device is provided, comprising:

[0005] A model chamber, in which a fracture-type reservoir model is placed, wherein the fracture-type reservoir model is formed by stacking and splicing natural dense rocks; the model chamber is provided with a fluid inlet and a fluid outlet;

[0006] A plurality of temperature and pressure sensors are arranged at different positions of the fracture type reservoir model, and are used to monitor the temperature and pressure at different positions of the fracture type reservoir model;

[0007] A fluid injection device, connected to the fluid inlet, for injecting fluid into the fracture-type reservoir model;

[0008] a fluid metering device, connected to the fluid outlet, for measuring the mass or volume of the fluid flowing out of the fracture-type reservoir model; and

[0009] The data acquisition system is electrically connected to the plurality of temperature and pressure sensors and is used to acquire temperature values ​​and pressure values ​​of the plurality of temperature and pressure sensors.

[0010] Furthermore, it also includes a high-precision infrared detector for detecting the temperature at different positions of the fracture-type reservoir model; the high-precision infrared detector is electrically connected to the data acquisition system, and the data acquisition system receives the temperature data detected by the high-precision infrared detector and displays an infrared thermal image.

[0011] Furthermore, it also includes a pressure display panel, which is electrically connected to the multiple temperature and pressure sensors and the data acquisition system, and the pressure display panel displays the pressure values ​​of the multiple temperature and pressure sensors.

[0012] Furthermore, it also includes a constant temperature box, the model bin is placed in the constant temperature box, and the constant temperature box is used to maintain the stability of the temperature in the model bin.

[0013] Furthermore, a bracket for supporting the model bin is provided under the model bin.

[0014] Furthermore, the fluid injection device includes a high-pressure pump and a valve connected by a pipeline.

[0015] Furthermore, the fluid metering device includes an electronic balance and a volume measuring container placed on the electronic balance.

[0016] Furthermore, the natural dense rock is any one of carbonate rocks, dense igneous rocks, and dense metamorphic rocks.

[0017] In a second aspect of the present application, there is provided a method for determining a connection path of a fractured oil reservoir using the above-mentioned testing device, comprising the following steps:

[0018] According to the fracture development characteristics of actual oil and gas reservoirs or the seismic carving results, a complex fracture reservoir model is formed under the model bin size conditions;

[0019] Placing the fracture type reservoir model in the model chamber, closing the fluid outlet, saturating the model chamber with fluid, and stabilizing the chamber at a first temperature for a period of time so that the temperature at each location in the fracture type reservoir model reaches a constant temperature value;

[0020] Turn on the data acquisition system and start collecting temperature and pressure data at various locations in the fracture reservoir model;

[0021] Fluid at a second temperature is injected into the fracture-type reservoir model through a fluid injection device, and the fluid outlet is opened. The connection path and dominant channel in the fracture-type reservoir model can be obtained through temperature and pressure change data; the absolute value of the difference between the second temperature and the first temperature is above 10°C.

[0022] Furthermore, it also includes using a high-precision infrared detector to detect temperature changes in the fracture-type reservoir model, and capturing the flow path of the fluid in the fracture-type reservoir model based on the infrared thermal imaging image, so as to obtain the connecting path and dominant channel in the fracture-type reservoir model.

[0023] Compared with the prior art, this application has the following technical effects:

[0024] A fracture-type oil reservoir connectivity path testing device of the present application has a fracture-type reservoir model formed by stacking and splicing natural dense rocks placed in the model chamber. Compared with the raw materials of existing cavity, glass etching and other technologies, it can better achieve the similarity with the actual oil and gas reservoir in terms of lithology, rock mechanical properties, wettability and other characteristics, can simulate the connectivity path of complex fracture channels, and the results of simulation tests are more reliable.

[0025] A fractured oil reservoir connection path testing device of the present application uses temperature changes and system pressure changes to jointly determine the connection path. The recorded pressure change law can be applied to oil field pressure monitoring data, providing a richer reference basis for simple pressure analysis, and further guiding people's development of fractured oil reservoirs, which is beneficial to improving the recovery rate of fractured oil reservoirs.

[0026] A fracture-type reservoir connection path testing device of the present application utilizes the temperature difference between the saturated fluid and the injected fluid to perform infrared temperature monitoring. Compared with the tracer method or the dye method, the implementation is more convenient, is conducive to the reuse of the testing device, and has less impact on the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0028] Figure 1 A schematic diagram of the overall structure of a fracture-type reservoir communication path testing device provided in an embodiment of the present application.

[0029] Among them, the reference numerals in the figure are:

[0030] 1. High-pressure pump, 2. Valve, 3. Constant temperature box, 4. Model chamber, 5. High-strength infrared-transmitting glass cover, 6. High-precision infrared detector, 7. Fluid inlet, 8. Connecting wires, 9. Temperature and pressure sensor, 10. Bracket, 11. Data acquisition system, 12. Pressure display panel, 13. Volume measurement container, 14. Electronic balance. DETAILED DESCRIPTION

[0031] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0032] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0033] It should be understood that the terms "length", "up", "down", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0034] In addition, the terms "first", "second", "third", "fourth", and "fifth" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", "third", "fourth", and "fifth" may explicitly or implicitly include one or more of the feature. In the description of this application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0035] See also Figure 1 Now, a fracture-type reservoir communication path testing device provided in an embodiment of the present application is described.

[0036] In one embodiment of the present application, a fracture-type reservoir communication path testing device of the embodiment of the present application includes a model bin 4, a plurality of temperature and pressure sensors 9, a fluid injection device, a fluid metering device, and a data acquisition system 11. A fracture-type reservoir model is placed in the model bin 4, and the fracture-type reservoir model is formed by stacking and splicing natural dense rocks; a fluid inlet 7 and a fluid outlet are provided on the model bin 4; a plurality of temperature and pressure sensors 9 are arranged at different positions of the fracture-type reservoir model, and are used to monitor the temperature and pressure at different positions of the fracture-type reservoir model; the fluid injection device is connected to the fluid inlet 7, and is used to inject fluid into the fracture-type reservoir model; the fluid metering device is connected to the fluid outlet, and is used to measure the mass or volume of the fluid flowing out of the fracture-type reservoir model; the data acquisition system 11 is electrically connected to the plurality of temperature and pressure sensors 9 through connecting wires 8, and is used to collect the temperature values ​​and pressure values ​​of the plurality of temperature and pressure sensors 9.

[0037] The temperature and pressure sensor 9 of the embodiment of the present application can simultaneously detect the temperature and pressure at the placement point.

[0038] The fractured reservoir model of the embodiment of the present application can be prepared according to the following method: select natural dense rocks that meet the lithological characteristics of the reservoir in the field outcrop or stone factory. According to the specific lithological characteristics of the actual reservoir, dense sedimentary rocks such as carbonate rocks, dense igneous rocks, dense metamorphic rocks and other rock types can be selected. This type of matrix rock must be natural rock, so that it meets the actual oil and gas reservoir characteristics in terms of mechanical properties, rock physical properties, especially wettability. The results of rock and mineral testing, rock mechanics testing, and wettability testing can be compared with the test results of oil and gas reservoirs, and the most similar rock blocks can be selected for standby. The matrix rock should be as large as possible, with a single rock length, width, and height of not less than 10cm, and preferably greater than 1m in length, width, and height. The rock is scaled and cut into several rock blocks according to the fracture cutting characteristics provided by the geophysical interpretation results of the reservoir, and the rock blocks are spliced ​​in their original positions to form a fractured reservoir model.

[0039] The model chamber 4 of the embodiment of the present application is a high-strength stainless steel cavity that can accommodate the above-mentioned fracture-type reservoir model and can withstand certain temperature and pressure conditions. The cavity is provided with multiple fluid inlets 7 and fluid outlets, multiple temperature and pressure sensors 9 are regularly arranged inside the cavity, and a high-strength infrared-transmitting glass cover 5 is provided on the cavity. When testing, the fluid inlet 7 and fluid outlet at the use position can be selected as needed, and the unused fluid inlet 7 and fluid outlet can be kept closed. The setting height of the fluid inlet 7, fluid outlet and temperature and pressure sensor 9 in the fracture-type reservoir model can also be adjusted to simulate the connection paths at different depths inside the fracture-type reservoir model.

[0040] The method for determining the connection path of a fractured oil reservoir using the testing device implemented in the present application comprises the following steps:

[0041] (1) Based on the fracture development characteristics of actual oil and gas reservoirs or seismic carving results, a complex fracture reservoir model is formed under the condition of model bin 4 size;

[0042] (2) placing the fractured reservoir model in the model chamber 4, closing the fluid outlet, and using the fluid injection device to saturate the model chamber 4 with fluid (when the values ​​measured by all temperature and pressure sensors 9 are consistent and no longer change, the model is determined to be saturated with fluid), and stabilizing it at the first temperature for a period of time (more than 4 hours) so that the temperature at various locations in the fractured reservoir model reaches a constant temperature value (at this time, the pressure and temperature at various locations inside the fractured reservoir model are uniform);

[0043] (3) Opening the data acquisition system 11 and starting to collect temperature and pressure data at various locations in the fracture reservoir model;

[0044] (4) Fluid at a second temperature is injected into the fracture-type reservoir model again through the fluid injection device, and the fluid outlet is opened. The connection path and dominant channel in the fracture-type reservoir model can be obtained through the temperature and pressure change data; the absolute value of the difference between the second temperature and the first temperature is above 10°C.

[0045] In the embodiment of the present application, a fluid with a large temperature difference is injected into the fracture-type reservoir model twice through a fluid injection device. For example, the first temperature is 60°C and the second temperature is 100°C. The fluid flow rate in the fracture is much greater than the heat exchange rate. As the fluid flows in the fracture, the pressure and temperature at the measuring point where the fluid flows will change significantly. The measured pressure and temperature values ​​are used as multi-point data to establish a prediction method for the plane distribution of pressure and temperature at different positions inside the model, which can be applied to actual oil reservoirs, and the connecting paths and dominant channels in the fracture-type reservoir model can be obtained, which can guide people's development of fracture-type oil reservoirs and help improve the recovery rate of fracture-type oil reservoirs.

[0046] The fluid injection device of the embodiment of the present application includes a high-pressure pump 1 and a valve 2 connected by a pipeline.

[0047] The fluid metering device of the embodiment of the present application includes an electronic balance 14 and a volume measurement container 13 placed on the electronic balance 14. The volume measurement container 13 can be a measuring cylinder or a beaker. The fluid metering device can accurately measure the mass and volume of the fluid flowing out of the fracture-type reservoir model during the test time, and can provide data reference for the dominant channels and recovery rate of the actual oil and gas reservoir.

[0048] Furthermore, a fracture-type reservoir communication path testing device according to an embodiment of the present application further includes a thermostat 3, in which the model chamber 4 is placed, and the thermostat 3 is used to maintain the stability of the temperature in the model chamber 4. When the ambient temperature changes greatly in a short period of time and it is difficult to maintain the temperature in the model chamber 4 stable, the model chamber 4 can be placed in the thermostat 3, and the thermostat 3 assists the model chamber 4 in maintaining the stability of its internal temperature, so as to reduce the influence of the ambient temperature change on the test results.

[0049] Furthermore, a bracket 10 for supporting the model chamber 4 is provided under the model chamber 4 of a fracture-type reservoir communication path testing device in an embodiment of the present application.

[0050] A fracture-type reservoir connection path testing device in an embodiment of the present application contains a fracture-type reservoir model formed by stacking and splicing natural dense rocks. Compared with the raw materials of existing cavity, glass etching and other technologies, it can better achieve the similarity with the actual oil and gas reservoir in terms of lithology, rock mechanical properties, wettability and other characteristics, and can simulate the connection path of complex fracture channels, and the results of simulation tests are more reliable.

[0051] A fractured oil reservoir connection path testing device in an embodiment of the present application uses temperature changes and system pressure changes to jointly determine the connection path. The recorded pressure change pattern can be applied to oil field pressure monitoring data, providing a richer reference basis for simple pressure analysis, and further guiding people's development of fractured oil reservoirs, which is beneficial to improving the recovery rate of fractured oil reservoirs.

[0052] Furthermore, a fractured reservoir communication path testing device of an embodiment of the present application further includes a high-precision infrared detector 6, which is used to detect the temperature at different positions of the fractured reservoir model; the high-precision infrared detector 6 is electrically connected to a data acquisition system 11, and the data acquisition system 11 receives the temperature data detected by the high-precision infrared detector 6 and displays an infrared thermal image. In this way, the high-precision infrared detector 6 can be used to detect temperature changes in the fractured reservoir model, and the flow path of the fluid in the fractured reservoir model can be captured according to the infrared thermal image, so as to obtain the communication path and dominant channel in the fractured reservoir model.

[0053] The method for determining the connection path of a fractured oil reservoir using the testing device implemented in the present application comprises the following steps:

[0054] (1) Based on the fracture development characteristics of actual oil and gas reservoirs or seismic carving results, a complex fracture reservoir model is formed under the condition of model bin 4 size;

[0055] (2) placing the fractured reservoir model in the model chamber 4, closing the fluid outlet, saturating the model chamber 4 with fluid using a fluid injection device, and stabilizing the model chamber 4 at a first temperature for a period of time so that the temperature at each location in the fractured reservoir model reaches a set constant temperature value, and calibrating the high-precision infrared detector 6 to the set temperature value;

[0056] (3) Opening the data acquisition system 11 and starting to collect temperature and pressure data at various locations in the fracture reservoir model;

[0057] (4) Inject the fluid of the second temperature into the fracture reservoir model again through the fluid injection device, open the fluid outlet, slowly adjust the inflow velocity, observe the infrared thermal imaging changes and the temperature and pressure plane changes, detect and obtain the pressure and temperature changes of each point in the fracture reservoir model in real time, and capture the infrared imaging plane of the model in real time, capture the fluid flow path, and obtain the connection path and dominant channel in the fracture reservoir model through the temperature and pressure change data; end this experiment after the fluid outlet no longer flows out of the fluid. The absolute value of the difference between the second temperature and the first temperature is above 10°C.

[0058] Furthermore, a fracture-type oil reservoir connection path testing device according to an embodiment of the present application also includes a pressure display panel 12, which is electrically connected to multiple temperature and pressure sensors 9 and a data acquisition system 11. The pressure display panel 12 displays the pressure values ​​of multiple temperature and pressure sensors 9, and can monitor the pressure values ​​at different positions in the fracture-type reservoir model during the reaction test in real time.

[0059] The embodiment of the present application uses infrared thermal imaging to quickly, intuitively and accurately reflect the connected paths and dominant channels within the fractured reservoir model, but infrared thermal imaging cannot be directly applied in actual oil reservoirs, and the data available in actual oil reservoirs are the temperature and pressure of different well points. Therefore, thermal imaging at different times in the experiment is used as a constraint, and the pressure and temperature values ​​of each measuring point are used as multi-point data to establish a prediction method for the plane distribution of pressure and temperature at different positions inside the model, which can then be applied to actual oil reservoirs.

[0060] A fracture-type reservoir connectivity path testing device in an embodiment of the present application utilizes the temperature difference between the saturated fluid and the injected fluid to perform infrared temperature monitoring. Compared with the tracer method, the implementation is more convenient (tracers have a high acquisition cost due to their rarity) and has less impact on the environment (commonly used tracers are mostly toxic and hazardous substances due to their trace detectability).

[0061] A fracture-type reservoir connection path testing device in an embodiment of the present application utilizes the temperature difference between the saturated fluid and the injected fluid to perform infrared temperature monitoring. Compared with the dye method, the implementation is more convenient (the dye needs to be selected according to the fluid properties and the acquisition cost is relatively high), and is conducive to the reuse of the test device (the dye remains on the model surface after use and needs to be cleaned or is difficult to clean).

[0062] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A method for determining the connection path of a fractured oil reservoir, It is characterized in that A fracture type reservoir communication path testing device is used, and the testing device comprises: A model chamber, in which a fracture-type reservoir model is placed, wherein the fracture-type reservoir model is formed by stacking and splicing natural dense rocks; the model chamber is provided with a fluid inlet and a fluid outlet; A plurality of temperature and pressure sensors are arranged at different positions of the fracture type reservoir model, and are used to monitor the temperature and pressure at different positions of the fracture type reservoir model; A fluid injection device, connected to the fluid inlet, for injecting fluid into the fracture-type reservoir model; a fluid metering device, connected to the fluid outlet, for measuring the mass or volume of the fluid flowing out of the fracture-type reservoir model; and A data acquisition system, electrically connected to the plurality of temperature and pressure sensors, for acquiring temperature values ​​and pressure values ​​of the plurality of temperature and pressure sensors; A high-precision infrared detector is used to detect the temperature at different positions of the fracture-type reservoir model; the high-precision infrared detector is electrically connected to the data acquisition system, and the data acquisition system receives the temperature data detected by the high-precision infrared detector and displays an infrared thermal image; The method comprises the following steps: According to the fracture development characteristics of actual oil and gas reservoirs or the seismic carving results, a complex fracture reservoir model is formed under the model bin size conditions; Placing the fracture type reservoir model in the model chamber, closing the fluid outlet, saturating the model chamber with fluid, and stabilizing the chamber at a first temperature for a period of time so that the temperature at each location in the fracture type reservoir model reaches a constant temperature value; Turn on the data acquisition system and start collecting temperature and pressure data at various locations in the fracture reservoir model; Injecting a fluid of a second temperature into the fracture-type reservoir model through a fluid injection device, and opening the fluid outlet, and obtaining the connection path and the dominant channel in the fracture-type reservoir model through the temperature and pressure change data; the absolute value of the difference between the second temperature and the first temperature is greater than 10°C; A high-precision infrared detector is used to detect temperature changes in the fracture-type reservoir model, and the flow path of the fluid in the fracture-type reservoir model is captured based on infrared thermal imaging images, so as to obtain the connected paths and dominant channels in the fracture-type reservoir model.

2. The method for determining the communication path of a fractured oil reservoir according to claim 1, It is characterized in that It also includes a pressure display panel, which is electrically connected to the multiple temperature and pressure sensors and the data acquisition system, and displays the pressure values ​​of the multiple temperature and pressure sensors.

3. The method for determining the communication path of a fractured oil reservoir according to claim 1, It is characterized in that It also includes a constant temperature box, in which the model bin is placed, and the constant temperature box is used to maintain the temperature in the model bin stable.

4. The method for determining the communication path of a fractured oil reservoir according to claim 1, It is characterized in that A bracket for supporting the model bin is provided under the model bin.

5. The method for determining the communication path of a fractured oil reservoir according to claim 1, It is characterized in that The fluid injection device includes a high-pressure pump and a valve connected by a pipeline.

6. The method for determining the communication path of a fractured oil reservoir according to claim 1, It is characterized in that The fluid metering device comprises an electronic balance and a volume measuring container placed on the electronic balance.

7. The method for determining the communication path of a fractured oil reservoir according to claim 1, It is characterized in that The natural dense rock is any one of carbonate rock, dense igneous rock and dense metamorphic rock.

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