System and method for determining properties of a temporary plugging agent

Abstract

The application provides a performance determination system and method of a temporary plugging agent, and the performance determination system comprises a control device, a fracture device, a containing device connected with an inlet of the fracture device, a back pressure pump connected with an outlet of the fracture device, and a confining pressure pump connected with a bottom of the fracture device. The containing device is used for containing a modified liquid to which the temporary plugging agent is added, the fracture device is used for simulating a fracture of a reservoir and receiving the modified liquid from the containing device, and the confining pressure pump is used for applying confining pressure to the fracture device. The back pressure pump is used for applying back pressure to the fracture device, and the control device is connected with the back pressure pump and the confining pressure pump, and is used for controlling a working state of the confining pressure pump according to a pressure value at the inlet of the fracture device, a pressure value of the back pressure pump and a pressure value of the confining pressure pump, and realizing more accurate determination of the performance of the temporary plugging agent according to a pressure change at the inlet of the fracture device within a preset time period.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of reservoir reconstruction, and in particular to a performance determination system and method for temporary plugging agent. BACKGROUND

[0002] Reservoir reconstruction plays an important role in increasing production of oil and gas. In the process of reservoir reconstruction, in order to achieve more uniform reconstruction or form a new reservoir, a water-soluble temporary plugging agent is added in hydraulic fracturing or an acid-soluble temporary plugging agent is added in acid fracturing for diversion acid fracturing. The temporary plugging agent will automatically dissolve in a certain period of time, has no pollution to the reservoir, and can improve the production of single well and the recovery rate of the block. Therefore, the evaluation of the temporary plugging performance of the temporary plugging agent is particularly important.

[0003] In the prior art, the evaluation of the temporary plugging performance of the temporary plugging agent is mainly realized by constructing a container for containing the temporary plugging agent, connecting the container to a simulated underground fracture through a simulated wellbore, pressurizing and heating the container containing the temporary plugging agent, then measuring the leakage amount of the temporary plugging agent, collecting the pressure change of the simulated wellbore, and thus evaluating the temporary plugging performance of the temporary plugging agent.

[0004] However, in the actual implementation process, the above method cannot accurately simulate the morphology of the underground fracture, so that the evaluation result of the temporary plugging performance of the temporary plugging agent is not accurate. SUMMARY

[0005] The present application provides a performance determination system and method for temporary plugging agent, which solves the problem that the evaluation result of the temporary plugging performance of the temporary plugging agent in the prior art is not accurate.

[0006] In a first aspect, the present application provides a performance determination system for temporary plugging agent, comprising: a control device, a fracture device, and a containing device connected to the inlet of the fracture device, a back pressure pump connected to the outlet of the fracture device, and a confining pressure pump connected to the bottom of the fracture device.

[0007] The containing device is used to contain the reconstruction fluid to which the temporary plugging agent is added.

[0008] The fracture device is used to simulate the fracture of the reservoir and receive the reconstruction fluid from the containing device.

[0009] The confining pressure pump is used to apply confining pressure to the fracture device.

[0010] The back pressure pump is used to apply back pressure to the fracture device.

[0011] The control device is connected to both the back pressure pump and the confining pressure pump, and is used to control the working state of the confining pressure pump based on the pressure value collected at the inlet of the fracture device, the pressure value of the back pressure pump, and the pressure value of the confining pressure pump, and to determine the performance of the temporary plugging agent based on the pressure change at the inlet of the fracture device within a preset time period.

[0012] In one possible design of the first aspect, the crack device comprises: a first semi-cylinder and a second semi-cylinder symmetrically distributed;

[0013] The first and second semi-cylinders have semi-elliptical grooves on their planes. The minor axis of the semi-ellipse forms the entrance of the fracture device, and the vertex of the major axis forms the exit of the fracture device. The grooves are provided with protrusions and depressions, which are used to simulate the surface morphology of the reservoir.

[0014] The first semi-cylinder and the second semi-cylinder are fixedly connected together by a fixing device.

[0015] In this possible design, the system further includes: a clamping device and a first thermostat mounted on the clamping device;

[0016] The clamping device is used to fix and seal the crack device;

[0017] The first thermostat is used to heat the clamping device to keep the clamping device within the target temperature range;

[0018] The control device is also used to collect the temperature of the first thermostat and control the working state of the first thermostat according to the temperature of the first thermostat.

[0019] In another possible design of the first aspect, the holding device includes: a first container and a stirring container connected to each other, wherein a stirring tool is disposed inside the stirring container;

[0020] The first container is used to hold the modification fluid with added temporary plugging agent. The stirring tool is connected to the driving device, and the driving device is connected to the control device. The driving device is used to control the stirring tool in the stirring container to stir the modification fluid in the stirring container under the control of the control device.

[0021] In this possible design, the system further includes: a second thermostat disposed on the first container and a third thermostat disposed on the stirring container;

[0022] The second thermostat is used to heat the first container to keep the first container within the target temperature range;

[0023] The third thermostat is used for heating the stirring container to keep the stirring container in a target temperature range.

[0024] In this possible design, the system further comprises a first displacement pump connected with the first container.

[0025] The first displacement pump is used for driving the reformed liquid in the first container to be transmitted to the stirring container.

[0026] In another possible design of the first aspect, the system further comprises a pressure sensor arranged between the inlet of the fracture device and the control device.

[0027] The pressure sensor is used for measuring the pressure at the inlet of the fracture device.

[0028] In still another possible design of the first aspect, the system further comprises a confining pressure gauge arranged between the confining pressure pump and the fracture device, and a back pressure gauge arranged between the back pressure pump and the fracture device.

[0029] The back pressure gauge is used for displaying the pressure of the back pressure pump.

[0030] The confining pressure gauge is used for displaying the pressure of the confining pressure pump.

[0031] In yet another possible design of the first aspect, the system further comprises a condensing device and a receiving container arranged at the outlet of the fracture device, and a weighing device used for carrying the receiving container.

[0032] The condensing device is used for cooling the reformed liquid flowing out of the fracture device.

[0033] The receiving container is used for receiving the cooled reformed liquid.

[0034] The weighing device is used for measuring the mass of the reformed liquid received by the receiving container.

[0035] In the second aspect, the embodiments of the present application provide a performance determination method of a temporary plugging agent, which is applied to the performance determination system of the temporary plugging agent in the first aspect and various possible designs.

[0036] When the pressure value of the back pressure pump is equal to the preset pressure value, the current pressure value at the inlet of the fracture device and the current pressure value of the confining pressure pump are obtained.

[0037] According to the current pressure value at the inlet of the fracture device and the current pressure value of the confining pressure pump, the pressure value output by the confining pressure pump is adjusted.

[0038] acquire pressure change at the entrance of the fracture device in a preset time period based on the pressure change output by the confining pressure pump;

[0039] determine the performance of the temporary plugging agent according to the pressure change at the entrance of the fracture device in the preset time period.

[0040] In a third aspect, an embodiment of the present application provides a computer readable storage medium, which stores computer program instructions. When the computer program instructions are executed by a processor, the computer program instructions are used to implement the performance determination method of the temporary plugging agent provided in the second aspect.

[0041] In a fourth aspect, an embodiment of the present application provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the computer program is used to implement the performance determination method of the temporary plugging agent provided in the second aspect.

[0042] The performance determination system and the performance determination method of the temporary plugging agent provided in the embodiments of the present application, the performance determination system includes a control device, a fracture device, and a containing device connected to the entrance of the fracture device, a back pressure pump connected to the outlet of the fracture device, and a confining pressure pump connected to the bottom of the fracture device. The containing device is used to contain the modified liquid to which the temporary plugging agent is added. The fracture device is used to simulate the fracture of the reservoir and receive the modified liquid from the containing device. The confining pressure pump is used to apply confining pressure to the fracture device. The back pressure pump is used to apply back pressure to the fracture device. The control device is connected to the back pressure pump and the confining pressure pump, and is used to control the working state of the confining pressure pump according to the acquired pressure value at the entrance of the fracture device, the pressure value of the back pressure pump and the pressure value of the confining pressure pump, and to determine the performance of the temporary plugging agent more accurately according to the pressure change at the entrance of the fracture device in a preset time period. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 A structure diagram of the performance determination system of the temporary plugging agent provided in the embodiments of the present application is provided.

[0044] Figure 2 A structure diagram of the fracture device in the performance determination system of the temporary plugging agent provided in the embodiments of the present application is provided.

[0045] Figure 3 A structure diagram of the first semi-cylinder in the fracture device provided in the embodiments of the present application is provided.

[0046] Figure 4 A structure diagram of the performance determination system of the temporary plugging agent provided in the embodiments of the present application is provided.

[0047] Figure 5 A structure diagram of the performance determination system of the temporary plugging agent provided in the embodiments of the present application is provided.

[0048] Figure 6 A flowchart of a performance determination method of the bridging agent provided in the embodiments of the present application is shown in the figure.

[0049] Figure 7 A structure diagram of a performance determination system of the bridging agent provided in the embodiments of the present application is shown in the figure. DETAILED DESCRIPTION

[0050] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described below in connection with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0051] Before introducing the embodiments of the present application, the professional terms and background technologies of the present application are first explained and described.

[0052] Hydraulic fracturing: a large amount of water mixed with chemicals is poured into shale layers to release natural gas.

[0053] Reservoir reconstruction is the most important process for oil and gas production, and plays a crucial role in the process of increasing production of oil wells, especially in the exploitation of tight oil and gas reservoirs and shale gas, reservoir reconstruction is indispensable.

[0054] Reservoir reconstruction for production increase has the advantages of low cost, high production increase and high economic benefit. With the increasing demand for oil and gas in today's society, reservoir reconstruction will play a more important role in oil and gas production. In the process of reconstruction, in order to achieve more uniform reconstruction or communication of new reservoirs, water-soluble bridging agents are added in hydraulic fracturing or acid-soluble bridging agents are added in acid fracturing for diversion acid fracturing. The bridging agent will automatically dissolve in a certain period of time, without pollution to the reservoir, which can improve the oil and gas production of single well and the recovery rate of the block, and has been widely used in major oil and gas fields at home and abroad.

[0055] The bridging performance is a key indicator for evaluating the bridging agent. At present, there are many experimental devices for evaluating the bridging performance of the bridging agent. The common method is to construct a container for containing the bridging agent, the container is connected with a simulated underground fracture through a simulated wellbore, and the container containing the bridging agent is pressurized and heated, then the leakage amount of the bridging agent is measured, the pressure change of the simulated wellbore is collected, and the bridging performance of the bridging agent is evaluated.

[0056] However, this way has problems of unscientific injection mode in experimental process, unreasonable accumulation mode of temporary plugging agent, inability to accurately simulate actual artificial fractures, inability to simultaneously realize dynamic and high-temperature temporary plugging, inability to meet long-time evaluation of temporary plugging capacity, and poor repeatability.

[0057] The present application aims at the above technical problems, and the technical concept of the inventor is as follows: the inventor finds that if the simulation fracture plate is modified, the gap between the actual artificial fracture and the experimental environment can be reduced, in addition, the actual hydraulic fracturing conditions can be simulated, the pressure data of the simulation fracture plate is collected for a long time in a reasonable way, so as to simultaneously realize dynamic and high-temperature temporary plugging, and the temporary plugging performance of the temporary plugging agent can be more accurately evaluated.

[0058] The technical solutions of the present application will be described in detail below through specific embodiments. It should be noted that the following specific embodiments can be combined with each other, and the same or similar concepts or processes can not be described again in some embodiments.

[0059] Figure 1 The structure schematic diagram of the performance determination system of the temporary plugging agent provided by the embodiment of the present application is shown in Figure 1. Figure 1 As shown in the figure, the performance determination system comprises a control device 10, a fracture device 11, a containing device 12 connected with the inlet of the fracture device 11, a back pressure pump 13 connected with the outlet of the fracture device 11, and a confining pressure pump 14 connected with the bottom of the fracture device 11.

[0060] The containing device 12 is used for containing the modified liquid to which the temporary plugging agent is added, the fracture device 11 is used for simulating the fracture of the reservoir and receiving the modified liquid from the containing device 12, the confining pressure pump 14 is used for applying confining pressure to the fracture device 11, the back pressure pump 13 is used for applying back pressure to the fracture device 10, the control device 10 is connected with the back pressure pump 13 and the confining pressure pump 14, and is used for controlling the working state of the confining pressure pump 14 according to the pressure value of the inlet of the fracture device 11, the pressure value of the back pressure pump 13 and the pressure value of the confining pressure pump 14, and determining the performance of the temporary plugging agent according to the pressure change of the inlet of the fracture device 11 within a preset time period.

[0061] Optionally, the control device 10 can be a computer or the like having the functions of issuing control instructions and collecting data of other devices.

[0062] Optionally, the preset time period can be the time length during which the pressure at the inlet of the fracture device 11 is maintained within a certain range under certain conditions, which can be 30 minutes or 60 minutes, and can be set according to actual conditions. In addition, the pressure values applied by the back pressure pump 13 and the confining pressure pump 14 can also be set according to actual conditions.

[0063] In one possible implementation, the back pressure pump 13 applies a back pressure of 2.5 MPa to the outlet of the fracture device 11. At this time, the pressure value of the confining pressure pump 14 is maintained above 20 MPa, which is more than 2 MPa higher than the pressure value at the inlet of the fracture device 11. It is determined that the pressure at the inlet of the fracture device 11 first gradually rises to above 5 MPa and is maintained above 5 MPa for more than 30 minutes. Then the pressure at the inlet of the fracture device 11 gradually decreases. This can confirm that the temporary plugging agent in the modification fluid has good dynamic temporary plugging performance.

[0064] The performance determination system for temporary plugging agents provided in this application includes: a control device, a fracturing device, a container connected to the inlet of the fracturing device, a backpressure pump connected to the outlet of the fracturing device, and a confining pressure pump connected to the bottom of the fracturing device. The container holds the modification fluid to which the temporary plugging agent has been added; the fracturing device simulates fractures in the reservoir and receives the modification fluid from the container; the confining pressure pump applies confining pressure to the fracturing device; the backpressure pump applies backpressure to the fracturing device; the control device is connected to both the backpressure pump and the confining pressure pump, and controls the operating state of the confining pressure pump based on the collected pressure values ​​at the inlet of the fracturing device, the pressure values ​​of the backpressure pump, and the pressure values ​​of the confining pressure pump, and achieves more accurate determination of the performance of the temporary plugging agent based on the pressure changes at the inlet of the fracturing device within a preset time period.

[0065] exist Figure 1 On this basis, Figure 2 A schematic diagram of the crack device in the performance determination system of the temporary plugging agent provided in this application embodiment. Figure 2 As shown, the crack device 11 includes: a first semi-cylinder 110 and a second semi-cylinder 111 symmetrically distributed.

[0066] Specifically, the first semi-cylinder 110 and the second semi-cylinder 111 form a fracture device 11 with a cylindrical shape, used to simulate fractures in the reservoir.

[0067] Combination Figure 3 The structure of the crack device 11 will be described. Figure 3 This is a schematic diagram of the structure of the first semi-cylinder in the cracking device provided in this application embodiment. This application embodiment uses the second semi-cylinder 111 for illustration. The second semi-cylinder 111 has a similar structure and shape to the first semi-cylinder 110, and will not be described in detail here.

[0068] Specifically, such as Figure 3 As shown, the second semi-cylinder 111 has a semi-elliptical groove 1101 on its plane. The short axis of the semi-ellipse forms the inlet 1102 of the fracture device 11, and the vertex of the long axis of the semi-ellipse forms the outlet 1103 of the fracture device 11. The groove 1101 has protrusions 114 distributed on it, which are used to simulate the surface morphology of the reservoir.

[0069] Optionally, the concave-convex object 114 can be a convex object or / and a concave object of any shape, Figure 3 For example, the convex object or / and the concave object can be circular, hexagonal, or quadrangular.

[0070] Further, in order to make Figure 2 The first semi-cylinder 110 and the second semi-cylinder 111 are fixedly connected together by the fixing device 112.

[0071] In a possible implementation, the fixing device 112 can include a hole 1121 and a nail 1121.

[0072] Specifically, the hole 1121 can be formed in the first semi-cylinder 110 and the second semi-cylinder 111, and then the first semi-cylinder 110 and the second semi-cylinder 111 can be aligned and fixed by the nail 1120. In the embodiment, four nails 1120 and four holes 1121 in each semi-cylinder are taken as an example. Figure 3 In the embodiment, only one nail 1120 and one hole 1121 are shown.

[0073] The shape of the nail 1120 is consistent with the shape of the hole 1121, and the shape of the nail 1120 and the hole 1121 is not limited herein, and can be a cylinder, a cube, a hexahedron, or other symmetrical shapes. Different from other fixing methods, the fixing device 112 not only fixes the first semi-cylinder 110 and the second semi-cylinder 111, but also facilitates disassembly, cleaning, or maintenance of the fracture device 11 when the fracture device 11 is not used.

[0074] It is worth noting that the material of the fracture device 11 requires temperature resistance, acid resistance, and pressure resistance, that is, the material meets the environmental requirements that can be borne by the reservoir fracture in actual work.

[0075] The performance determination system of the temporary plugging agent provided in the embodiment includes a first semi-cylinder and a second semi-cylinder which are symmetrically distributed. The first semi-cylinder and the second semi-cylinder are provided with a semi-elliptical groove in a plane, a short axis of the semi-elliptical groove forms an inlet of the fracture device, a top point of a long axis of the semi-elliptical groove forms an outlet of the fracture device, a concave-convex object is distributed on the groove, the concave-convex object is used for simulating a surface morphology of a reservoir, and the first semi-cylinder and the second semi-cylinder are fixedly connected together by a fixing device. The fracture device simulates the fracture of the reservoir, and provides a reliable basis for more accurate performance determination of the temporary plugging agent.

[0076] On the basis of the above-described embodiment, Figure 4 FIG. 2 is a structural schematic diagram of a second embodiment of the performance determination system of the temporary plugging agent provided in the embodiment. Figure 4As shown, the performance determination system further comprises a clamping device 15 and a first thermostat 151 arranged on the clamping device 15.

[0077] The clamping device 15 is used to fix and encapsulate the crack device 11, and the first thermostat 151 is used to heat the clamping device 15 to keep the clamping device 15 in a target temperature range.

[0078] Optionally, the clamping device 15 can be a non-conventional clamp, and the material requirement is that it is resistant to temperature, acid and pressure. The size of the rubber tube of the clamping device 15 meets the size of the crack device 11.

[0079] Optionally, the control device 10 is further configured to collect the temperature of the first thermostat 151 and control the working state of the first thermostat 151 according to the temperature of the first thermostat 151.

[0080] In a possible implementation, the temperature of the crack device 11 is required to be not greater than 90°, at this time, the control device 10 collects the temperature of the first thermostat 151 which is much lower than 90°, and needs to control the first thermostat 151 to heat the clamping device 15. In order to avoid the temperature greater than 90°, the control device 10 collects the temperature of the first thermostat 151 in real time, for example, when the temperature of the first thermostat 151 is 85°, the control device 10 controls the first thermostat 151 to stop heating, at this time, the temperature of the crack device 11 is about 85°.

[0081] The performance determination system of the temporary plugging agent provided by the embodiment of the application, wherein the crack device is wrapped by the clamping device, and the first thermostat is arranged on the clamping device. The clamping device is used to fix and encapsulate the crack device, and the first thermostat is used to heat the clamping device to keep the clamping device in a target temperature range. The control device is further configured to collect the temperature of the first thermostat and control the working state of the first thermostat according to the temperature of the first thermostat. The crack device and the first thermostat realize the simulation and fixation of the temperature environment of the crack device, and provide a reliable basis for more accurately determining the performance of the temporary plugging agent in the future.

[0082] On the basis of the above embodiment, Figure 5 The structure diagram of the performance determination system of the temporary plugging agent provided by the embodiment of the application is shown in FIG. 3. Figure 5 As shown, the holding device 12 in the performance determination system comprises a first container 120 and a stirring container 121 connected with each other, and a stirring tool 1210 is arranged in the stirring container 121.

[0083] In a possible implementation, the number of the holding devices 12 is changed according to the amount of the reconstruction fluid, that is, the number of the first containers 120 and the stirring containers 121 connected with each other can be increased or decreased in pairs, for example, when the amount of the reconstruction fluid is large, the number of the first containers 120 and the stirring containers 121 can be 2, 3 or even more, respectively.

[0084] In another possible implementation, when the amount of the reconstruction fluid is large, the number of the first containers 120 and the stirring containers 121 can be 1 respectively, and the first container 120 and the stirring container 121 are alternately used in the performance determination process of the temporary plugging agent, so as to reduce the use cost of the containers.

[0085] The first container 120 is used for holding the reconstruction fluid to which the temporary plugging agent is added, the stirring tool 1210 is connected with the driving device 122, the driving device 122 is connected with the control device 10, and the driving device 122 is used for controlling the stirring tool 1210 in the stirring container 121 to stir the reconstruction fluid in the stirring container 121 under the control of the control device 10.

[0086] Optionally, the stirring tool 1210 stirs the reconstruction fluid in the stirring container 121, so that the reconstruction fluid to which the temporary plugging agent is added in the stirring container 121 is uniformly mixed.

[0087] The driving device 122 can be a motor.

[0088] In a possible implementation, the performance determination system further includes a second constant temperature instrument 1200 arranged on the first container 120 and a third constant temperature instrument 1211 arranged on the stirring container 121.

[0089] The second constant temperature instrument 1200 is used for heating the first container 120, so as to keep the first container 120 in a target temperature range, and the third constant temperature instrument 1211 is used for heating the stirring container 121, so as to keep the stirring container 121 in the target temperature range.

[0090] Optionally, the number of the first containers 120 and the stirring containers 121 determines the number of the constant temperature instruments, and each constant temperature instrument corresponds to one first container 120 or one stirring container 121. It should be noted that the constant temperature instrument can be replaced by other devices with similar functions.

[0091] In a possible implementation, the performance determination system further includes a first displacement pump 1201 connected with the first container 120.

[0092] Optionally, the first displacement pump 1201 is used for driving the reconstruction fluid in the first container 120 to be transmitted to the stirring container 121.

[0093] In a possible implementation, the performance determination system further comprises a pressure sensor 16 arranged between the inlet of the fracture device 11 and the control device 10.

[0094] Optionally, the pressure sensor 16 is configured to measure the pressure at the inlet of the fracture device 11.

[0095] In a possible implementation, the performance determination system further comprises a back pressure gauge 131 arranged between the back pressure pump 13 and the fracture device 11, and a confining pressure gauge 141 arranged between the confining pressure pump 14 and the fracture device 11.

[0096] Optionally, the back pressure gauge 131 is configured to display the pressure of the back pressure pump 13, and the confining pressure gauge 141 is configured to display the pressure of the confining pressure pump 14.

[0097] In a possible implementation, the performance determination system further comprises a condensing device 17 and a receiving container 18 arranged at the outlet of the fracture device 11, and a weighing device 19 configured to weigh the receiving container 18.

[0098] Optionally, the condensing device 17 is configured to cool the modified fluid flowing out of the fracture device 11, the receiving container 18 is configured to receive the cooled modified fluid, and the weighing device 19 is configured to measure the mass of the modified fluid received by the receiving container 18.

[0099] In the performance determination system described above, the performance determination system can further comprise a recovery container 1202 and a back pressure valve 132.

[0100] The recovery container 1202 can be configured to receive the fluid medium of the first displacement pump 1201 and the modified fluid of the first container 120, and the back pressure valve 132 can be configured to control whether the pressure of the back pressure pump 13 is applied to the fracture device 11.

[0101] It is worth noting that the connection between the control device 10 and the devices controlled by the control device 10 in the performance determination system described above can be wireless connection or wired connection. Pipes, valves and / or switches can be added between the devices through which the modified fluid flows to perfect the implementation process of the specific performance determination method. The switches or valves can be controlled by the control device 10.

[0102] The performance determination system of the temporary plugging agent provided in the embodiment of the application is based on the control device, the fracture device, the containing device including the first container and the stirring container connected with each other, the confining pressure pump and the back pressure pump, and further includes the second constant temperature instrument arranged on the first container, the third constant temperature instrument arranged on the stirring container, the pressure sensor arranged between the inlet of the fracture device and the control device, the confining pressure gauge arranged between the confining pressure pump and the fracture device, the back pressure gauge arranged between the back pressure pump and the fracture device, the condensing device and the receiving container arranged at the outlet of the fracture device, and the weighing device for bearing the receiving container, so that the implementation basis for more accurately determining the performance of the temporary plugging agent is provided.

[0103] On the basis of the above-mentioned embodiment, Figure 6 The flowchart of the performance determination method of the temporary plugging agent provided in the embodiment of the application is shown in the figure. Figure 6 As shown in the figure, the performance determination method includes the following steps.

[0104] In step 61, when the pressure value of the back pressure pump is at a preset pressure size, the current pressure value at the inlet of the fracture device and the current pressure value of the confining pressure pump are obtained.

[0105] In the present scheme, the devices through which the temporary plugging agent in the performance determination system flows are connected by pipelines, valves and / or switches, wherein the pipelines, valves and / or switches should have the characteristics of temperature resistance, pressure resistance and acid resistance. The devices connected with the control device have been described in the above-mentioned embodiment, and will not be repeated here.

[0106] In the present step, the pressure value of the back pressure pump is adjusted to be at a preset pressure size, that is, the back pressure is added to the fracture device, and the added back pressure value is the preset pressure. At this time, the control device obtains the current pressure value at the inlet of the fracture device and the current pressure value of the confining pressure pump.

[0107] The current pressure value of the confining pressure pump can be the confining pressure value applied to the fracture device, for simulating the pressure suffered by the fractures of the reservoir.

[0108] In step 62, the pressure size output by the confining pressure pump is adjusted according to the current pressure value at the inlet of the fracture device and the current pressure value of the confining pressure pump.

[0109] In the present step, since the current pressure value at the inlet of the fracture device is in a process of continuous change with the flow of the modification liquid, in order to more accurately simulate the environment of the fractures of the reservoir in the hydraulic fracturing, the current pressure value of the confining pressure pump needs to be adjusted so that the pressure value of the confining pressure pump is higher than the pressure value at the inlet of the fracture device by a certain threshold range.

[0110] In a possible implementation, if the threshold range is greater than 2 MPa, the current pressure value at the inlet of the fracture device and the current pressure value of the confining pressure pump are obtained, it is judged whether the current pressure value of the confining pressure pump is greater than the current pressure value at the inlet of the fracture device by 2 MPa, if not, the control device controls the confining pressure pump to increase the pressure until the pressure value of the confining pressure pump is higher than the pressure value at the inlet of the fracture device by more than 2 MPa.

[0111] Optionally, the current pressure value at the inlet of the fracture device changes continuously, and the current pressure value of the confining pressure pump is adjusted accordingly.

[0112] Step 63, based on the pressure change of the confining pressure pump, the pressure change at the inlet of the fracture device in a preset time period is collected.

[0113] In this step, in the preset time period, the pressure output by the confining pressure pump should be always higher than the pressure at the inlet of the fracture device, and the pressure change at the inlet of the fracture device is collected according to the pressure change of the confining pressure pump in the preset time period.

[0114] The pressure change at the inlet of the fracture device corresponds to the time interval, which is convenient for subsequent analysis.

[0115] Step 64, according to the pressure change at the inlet of the fracture device in the preset time period, the performance of the temporary plugging agent is determined.

[0116] In this step, the pressure change law at the inlet of the fracture device in the preset time period is equivalent to the pressure change law in the hydraulic fracturing environment in the fracture of the reservoir, and the performance of the temporary plugging agent is determined by analyzing the pressure change at the inlet of the fracture device.

[0117] In a possible implementation, the preset time period can be 30 min, when the pressure at the inlet of the fracture device rises to 5 MPa, the 30 min is started to be counted, that is, the pressure at the inlet of the fracture device is maintained for more than 30 min, and it can be determined that the temporary plugging agent has good dynamic temporary plugging performance.

[0118] The performance determination method of the temporary plugging agent provided by the embodiment of the application, by adjusting the pressure output by the confining pressure pump when the pressure value of the back pressure pump is at a preset pressure size, and adjusting the pressure output by the confining pressure pump according to the current pressure value at the inlet of the fracture device and the current pressure value of the confining pressure pump. Then based on the pressure change of the confining pressure pump, the pressure change at the inlet of the fracture device in a preset time period is collected. Finally, according to the pressure change at the inlet of the fracture device in the preset time period, the performance of the temporary plugging agent is determined. In this method, by adjusting the pressure output by the confining pressure pump and collecting the pressure change at the inlet of the fracture device in a preset time period, the performance of the temporary plugging agent is determined more accurately.

[0119] In the following, the technical solutions possibly involved in the present application will be illustrated in connection with an actual performance determination system for temporary plugging agents and a performance determination method.

[0120] Figure 7 A structural schematic diagram of the performance determination system for temporary plugging agents according to Embodiment Four of the present application is shown in FIG. 4. Figure 7 As shown in FIG. 4, based on the structure shown in FIG. 3, the holding device 12 can include two first containers (for convenience, denoted as first container A and first container B) and two stirring containers (denoted as stirring container A and stirring container B). Figure 5 In the first container A, a second constant temperature instrument 1200 is arranged; in the first container B, a fourth constant temperature instrument 1201 is arranged; in the stirring container A, a third constant temperature instrument 1211 is arranged; in the stirring container B, a fifth constant temperature instrument 1212 is arranged; between the control device 10 and the first container A, a first displacement pump 1201 is arranged; between the control device 10 and the first container B, a second displacement pump 1203 is arranged; between the control device 10 and the stirring container A, a driving device 122 is arranged; between the control device 10 and the stirring container B, a driving device 123 is arranged.

[0121] Optionally, a second switch F2 is arranged on the pipeline between the first container A and the stirring container A; a first switch F1 is arranged on the pipeline between the first container B and the stirring container B; a fourth switch F4 and a fifth switch F5 are arranged on the pipeline between the stirring container A and the fracture device 11; a third switch F3 and a fifth switch F5 are arranged on the pipeline between the stirring container B and the fracture device 11; an eighth switch F8 is arranged between the fracture device 11 and the confining pressure gauge 141; a sixth switch F6 is arranged between the fracture device 11 and the back pressure valve 132; a sixth switch F6 is arranged between the back pressure gauge 131 and the back pressure valve 132; a seventh switch F7 is arranged between the back pressure valve 132 and the back pressure gauge 131; a ninth switch F9 is arranged on the pipeline between the recovery container 1202 and the first displacement pump 1201; a tenth switch F10 is arranged on the pipeline between the recovery container 1202 and the second displacement pump 1203.

[0122] The fifth switch F5 is a total switch for controlling the delivery of the modified liquid in the stirring container A and the stirring container B to the fracture device 11.

[0123] In one possible implementation, when the amount of the temporary plugging agent to be determined is small, the performance determination process is as follows:

[0124]

[0125] ​Step 1, the control device 10 controls the first switch F1, the third switch F3, the fifth switch F5, the sixth switch F6, the seventh switch F7 and the eighth switch F8 open, and the other switches are closed. The first thermostat 151, the second thermostat 1200 and the third thermostat 1211 are used to preheat the clamping device 15, the first container A and the stirring container A respectively, and the preheating temperature is not more than 90°.

[0126] Step 2, the modified liquid with temporary plugging agent is preheated and added to the first container A and the stirring container A, and the temperature is raised to not more than 90°, and then the heating is stopped and the temperature is kept constant. At this time, the stirring device in the stirring container A is started by the driving device A, and the modified liquid in the stirring container A is stirred.

[0127] Step 3, the confining pressure pump 14 applies a confining pressure of 20 MPa or more to the clamping device 15, and the back pressure pump 13 applies a back pressure of 2.5 MPa to the outlet 1103 of the fracture device 11, and the first displacement pump 1201 is started to continuously transport the modified liquid in the first container A to the stirring container A.

[0128] Step 4, the control device 10 continuously collects the pressure change of the pressure sensor 16, the mass of the weighing device 19 (the modified liquid flowing out of the outlet 1103 of the fracture device 11 and cooled by the condensing device 17), the temperature of the first thermostat 151, the second thermostat 1200 and the third thermostat 1211, and the pressure data of the back pressure gauge 131 and the confining pressure gauge 141. And adjust the output pressure of the confining pressure pump 14, so that the output pressure of the confining pressure pump 14 is always greater than the pressure at the inlet of the fracture device 11 by 2 MPa or more.

[0129] Step 5, judge the pressure change at the inlet of the fracture device 11: first rise, when rising to 5 MPa or more, start to record whether the pressure of 5 MPa or more is greater than 30 min, if greater, it means that the temporary plugging agent has good dynamic temporary plugging performance; if not, it means that the temporary plugging agent does not have good dynamic temporary plugging performance.

[0130] In another possible implementation, when the amount of temporary plugging agent to be determined is large, the performance determination process is as follows:

[0131] Step 1, the control device 10 controls the first switch F1, the second switch F2, the third switch F3, the fifth switch F5, the sixth switch F6, the seventh switch F7 and the eighth switch F8 to open, and the other switches are closed. The first thermostat 151, the second thermostat 1200, the third thermostat 1211, the fourth thermostat 1201 and the fifth thermostat 1212 are used to preheat the clamping device 15, the first container A, the stirring container A, the first container B and the stirring container B respectively, and the preheating temperature is not more than 90°.

[0132] Step 2, the modified fluid with temporary blocking agent is preheated and added to the first container B, stirring container B, and the temperature is raised to no more than 90 °, then stop heating, keep constant temperature. At this time, the stirring device in stirring container B is started by driving device B, and the modified fluid in stirring container B is stirred.

[0133] Step 3, the confining pressure pump 14 adds confining pressure 20 MPa or more to the clamping device 15, the back pressure pump 13 adds back pressure 2.5 MPa to the outlet 1103 of the fracture device 11, and the second displacement pump 1203 is started to continuously transport the modified fluid in the first container B to the stirring container B.

[0134] Step 4, the control device 10 continuously collects the pressure change of the pressure sensor 16, the mass of the weighing device 19 (the modified fluid flowing out of the outlet 1103 of the fracture device 11 and cooled by the condensing device 17), the temperature of the first thermostat 151, the fourth thermostat 1201, and the fifth thermostat 1212, and the pressure data of the back pressure gauge 131 and the confining pressure gauge 141. The output pressure of the confining pressure pump 14 is adjusted so that the output pressure of the confining pressure pump 14 is always greater than the pressure at the inlet 1102 of the fracture device 11 by 2 MPa or more.

[0135] Step 5, the modified fluid with temporary blocking agent is preheated and added to the first container A, stirring container A.

[0136] Step 6, the first displacement pump 1201 is started to continuously transport the modified fluid in the first container A to the stirring container A, and when the modified fluid in the first container A is displaced by about half, the temperature of the first container A and the stirring container A is raised to no more than 90 °, and the stirring device in the stirring container A is started by the driving device A to stir the modified fluid in the stirring container A.

[0137] Step 7, when the pump pressure of the driving device A starts to rise, the driving device A is paused.

[0138] Step 8, when the modified fluid in the first container B is close to being displaced, the driving device A is started, and when the pump pressure of the driving device A approaches the pressure 1102 of the inlet of the fracture device 11, the control device 10 controls the fourth switch F4 to open, closes the third switch F3 and the driving device B, and opens the ninth switch F9 and the tenth switch F10 to receive the fluid medium of the first displacement pump 1201 and the second displacement pump 1203, and the modified fluid of the first container A and the first container B.

[0139] Step 9, at this time, the control device 10 determines the change of the crack device 11 inlet according to the obtained change, that is, first rising, rising to 5 MPa or more, and then recording whether the pressure maintained at 5 MPa or more is greater than 30 min. If it is greater, it means that the temporary plugging agent has good dynamic temporary plugging performance. If it is not greater, it means that the temporary plugging agent does not have good dynamic temporary plugging performance.

[0140] In another possible implementation, when the amount of temporary plugging agent to be determined is relatively large and has exceeded the sum of the first container A, the first container B, the stirring container A and the stirring container B, the operations of steps 5 to 8 in the case of the relatively large amount of temporary plugging agent can be repeated.

[0141] The embodiment of the application also provides a temporary plugging agent performance determination system, which has similar or identical parts to the above embodiment and will not be described herein again. The temporary plugging agent performance determination system solves the problem that the temporary plugging performance of the temporary plugging agent is not accurately evaluated in different amounts of modified liquid.

[0142] The embodiment of the application also provides a chip for executing the temporary plugging agent performance determination scheme in the above embodiment.

[0143] The embodiment of the application also provides a computer readable storage medium, which stores computer instructions. When the computer instructions are executed on a computer, the computer executes the temporary plugging agent performance determination scheme in the above embodiment.

[0144] The computer readable storage medium can be implemented by any type of volatile or nonvolatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk or optical disk. The readable storage medium can be any available medium that can be accessed by a general-purpose or special-purpose computer.

[0145] Optionally, the readable storage medium is coupled to the processor, so that the processor can read information from the readable storage medium and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can be located in an application specific integrated circuit (ASIC). Of course, the processor and the readable storage medium can also exist as discrete components in the device.

[0146] Those skilled in the art can understand that all or part of the steps of the above-mentioned method embodiments can be completed by program instruction related hardware. The foregoing program can be stored in a computer readable storage medium. The program executes to perform the steps of the above-mentioned method embodiments; and the foregoing storage medium includes various storage media that can store program codes, such as ROM, RAM, magnetic disk or optical disk.

[0147] The embodiments of the present application also provide a computer program product, which comprises a computer program stored in a computer readable storage medium. At least one processor can read the computer program from the computer readable storage medium, and the at least one processor executes the computer program to implement the scheme for determining the performance of the bridging agent in the above embodiments.

[0148] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than limit them; although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the above embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A system for determining the performance of a bridging agent, the system comprising: The device comprises a control device, a fracture device, a holding device connected with the inlet of the fracture device, a back pressure pump connected with the outlet of the fracture device, and a confining pressure pump connected with the bottom of the fracture device. The holding device is used for holding the modified liquid added with the temporary plugging agent. The fracture device is used for simulating the fracture of the reservoir and receiving the modified liquid from the holding device. The confining pressure pump is used for applying confining pressure to the fracture device, and a confining pressure table is arranged between the confining pressure pump and the fracture device. The back pressure pump is used for applying back pressure to the fracture device, and a back pressure table and a back pressure valve are arranged between the back pressure pump and the fracture device. The control device is connected with the back pressure pump and the confining pressure pump. The holding device comprises a first container and a first stirring container connected with each other, and a second container and a second stirring container connected with each other. A first displacement pump is arranged between the control device and the first container, and a second displacement pump is arranged between the control device and the second container. When the pressure value of the back pressure pump is a preset pressure value, the current pressure value at the inlet of the fracture device and the current pressure value of the confining pressure pump are obtained. According to the current pressure value at the inlet of the fracture device and the current pressure value of the confining pressure pump, the pressure value output by the confining pressure pump is adjusted. The current pressure value of the confining pressure pump is adjusted so that the pressure value of the confining pressure pump is higher than the pressure value at the inlet of the fracture device by a certain threshold range. If the threshold range is greater than 2 MPa, the current pressure value at the inlet of the fracture device and the current pressure value of the confining pressure pump are obtained, and it is judged whether the current pressure value of the confining pressure pump is greater than the current pressure value at the inlet of the fracture device by 2 MPa. If not, the control device controls the confining pressure pump to increase the pressure until the pressure value of the confining pressure pump is higher than the pressure value at the inlet of the fracture device by more than 2 MPa. Based on the pressure change output by the confining pressure pump, the pressure change at the inlet of the fracture device in a preset time period is collected. According to the pressure change at the inlet of the fracture device in the preset time period, the performance of the temporary plugging agent is determined.

2. The system of claim 1, wherein, The control device adjusts the change of the inlet of the fracture device as follows: first rising, rising to more than 5 MPa, and then recording whether the pressure of more than 5 MPa is maintained for more than 30 minutes. If yes, it indicates that the temporary plugging agent has good dynamic temporary plugging performance. If not, it indicates that the temporary plugging agent does not have good dynamic temporary plugging performance. Further comprising: a clamping device and a first constant temperature instrument arranged on the clamping device; 3. The system of claim 1, wherein, The clamping device is used for fixing and packaging the fracture device. The first constant temperature instrument is used for heating the clamping device to keep the clamping device in a target temperature range. The control device is also used for collecting the temperature of the first constant temperature instrument and controlling the working state of the first constant temperature instrument according to the temperature of the first constant temperature instrument. Further comprising: a second constant temperature instrument arranged on the first container and a third constant temperature instrument arranged on the stirring container; The second thermostat is used to heat the first container to keep the first container in a target temperature range; The third thermostat is used to heat the stirring container to keep the stirring container in a target temperature range.

4. The system according to any one of claims 1-3, characterized in that, Further comprising: A pressure sensor arranged between the inlet of the crack device and the control device; The pressure sensor is used to measure the pressure at the inlet of the crack device.

5. The system according to any of claims 1-3, characterized in that, Further comprising: A condensing device and a receiving container arranged at the outlet of the crack device, and a weighing device for carrying the receiving container; The condensing device is used to cool the modified liquid flowing out of the crack device; The receiving container is used to receive the cooled modified liquid; The weighing device is used to measure the mass of the modified liquid received by the receiving container.

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