Fracturing fluid evaluation device and evaluation method

Abstract

The present invention belongs to the technical field of oil extraction and discloses a fracturing fluid evaluation device and evaluation method. The device includes a constant speed displacement pump, an intermediate container, a high and low temperature test chamber, a resistivity measuring device, a trickle pipe, a recovery device, and a data acquisition system. The comprehensive evaluation test device for fracturing fluid of the present invention uses a displacement pump to pump the sample into the pipe for stable flow, which better simulates the flow conditions of the actual liquid in the oil field, improves the authenticity of the test, and calculates the drag reduction rate of the fracturing fluid; the present invention uses an intermediate container to simulate the temperature and pressure under formation conditions, which can accurately measure the gelation and gel breaking conditions of the fracturing fluid.

Description

Technical Field

[0001] The invention belongs to the technical field of petroleum extraction, and in particular relates to a fracturing fluid evaluation device and an evaluation method. Background Art

[0002] Fracturing involves pumping high-pressure fluid into the formation, opening fractures and creating multiple seepage channels. This process then carries proppant from the fluid into the fractures, propping them open and reducing resistance to fluid flow. In recent years, advances and large-scale application of horizontal well and volume fracturing technologies in unconventional oil and gas reservoirs have enabled the efficient and economic development of unconventional oil and gas resources. Shale gas is an unconventional natural gas found in mudstone with extremely low permeability and porosity, primarily in adsorbed, dissolved, or free forms. Countries around the world are increasing their efforts to develop shale gas resources. Shale gas reservoirs have virtually no natural production capacity, making fracturing a primary production-enhancing measure for economically efficient development. Over the past decade, my country has achieved breakthroughs in both fracturing fluid systems and fracturing fluid flowback treatment technologies for shale gas development, laying the foundation for future large-scale production through experimental and field application. Slickwater fracturing fluid is currently the most widely used in shale gas development. However, current laboratory evaluation of this fluid has certain limitations. The most important parameter is drag reduction, but drag reduction is currently evaluated using a single instrument. Evaluating drag reduction before and after gel breakage requires constant fluid replacement, resulting in inaccurate and cumbersome data. Evaluations of crosslinking and gel breakage properties are performed at ambient temperature and pressure, which is not representative and cannot reveal gel formation and gel breakage under formation conditions. Furthermore, gel formation and gel breakage are typically evaluated using a hanging observation method, which lacks data support. Summary of the Invention

[0003] In order to overcome the shortcomings of the existing technology, the present invention provides a fracturing fluid evaluation device and evaluation method, which uses a displacement pump to pump the sample into the pipeline for stable flow, better simulating the actual flow conditions of the liquid in the oil field, improving the authenticity of the test, and calculating the fracturing fluid drag reduction rate.

[0004] The above-mentioned object of the present invention is achieved through the following technical solutions: a fracturing fluid evaluation device, comprising a constant-speed displacement pump, an intermediate container, a high-temperature and low-temperature test chamber, a resistivity measuring device, a trickle pipe, a recovery device, and a data acquisition system; wherein five constant-speed displacement pumps are provided, and constant-speed displacement pumps a, constant-speed displacement pump b, constant-speed displacement pump c, and constant-speed displacement pump d are connected to the intermediate container placed in the high-temperature and low-temperature test chamber a through pipelines; valve a and pressure gauge a are provided in sequence on the pipeline connecting the constant-speed displacement pump a and the intermediate container; valve b and valve e are provided in sequence on the pipeline connecting the constant-speed displacement pump b and the intermediate container; valve c, valve f, and valve e are provided in sequence on the pipeline connecting the constant-speed displacement pump c and the intermediate container; valve d is provided in sequence on the pipeline connecting the constant-speed displacement pump d and the intermediate container; the constant-speed displacement pump e pipeline is connected to a back-pressure device; and valve l and pressure gauge d are provided in sequence on the pipeline connecting the constant-speed displacement pump e and the back-pressure device; The intermediate container is provided with a simulation pipeline, a resistivity meter, and a camera arranged above the resistivity meter. The resistivity meter is connected to the resistivity measuring device outside the intermediate container through a line; the pipeline above the intermediate container and the pipeline below are merged and connected to the trickle pipeline placed in the high and low temperature test box b, and a valve j is provided on the merged line, a valve h is provided on the pipeline above the intermediate container, and a valve g is provided on the pipeline below the intermediate container. The other end of the trickle pipeline is connected to a back pressure device, and a valve k is provided on the connecting pipeline; the back pressure device is also connected to a recovery device, and a valve m is provided on the connecting pipeline; a branch is also provided on the pipeline above the intermediate container to connect the trickle pipeline and the back pressure device, and a pressure gauge b and a valve i are provided on the branch in sequence; a pressure gauge c is provided on one end of the trickle pipeline connected to the intermediate container, and a branch is connected to the data acquisition system at the end, and the data acquisition system is further connected to the connecting pipeline of the trickle pipeline and the back pressure device.

[0005] According to the evaluation method of the above-mentioned fracturing fluid evaluation device, the steps are as follows: confirm that all valves are closed, load fracturing fluid into the constant speed displacement pump b, load gel breaker into the constant speed displacement pump c, load clean water into the constant speed displacement pump d, open valve e, displace the fracturing fluid into the simulated pipeline of the intermediate container, close valve b and valve e, adjust the temperature and pressure of the high and low temperature test box a to the same formation conditions, use a camera to observe the fracturing fluid out of the simulated pipeline wall and detect the resistivity of the fracturing fluid through a resistivity meter, transmit the resistivity data to the resistivity meter for graph drawing, and determine the gel formation of the fracturing fluid through resistivity graph transformation; open valve a and use constant speed displacement pump a to adjust the annulus pressure; open valve d, valve f, valve g, valve j, and pump clean water into the trickle pipeline through the constant speed displacement pump d, and and the data acquisition system to measure the resistance of clean water, close valves d and f, open valve b, pump the fracturing fluid into the trickle pipe through the constant speed displacement pump b, test its resistance through the pressure difference on both sides and the data acquisition system, and measure the resistance reduction rate through the above test; close valves b and g, open valves c, e, and f, pump the gel breaker into the simulated pipe, observe the gel breaking situation, observe the fracturing fluid situation at the simulated pipe wall through the camera, detect the resistivity of the fracturing fluid through the resistivity meter, transmit the resistivity data to the resistivity measuring device for graph drawing, and determine the gel breaking situation of the fracturing fluid through the resistivity graph transformation; open valves h and j, use the constant speed displacement pump d to pump out clean water to push the gel breaking fluid into the trickle pipe to test the resistance reduction rate, and the tested fracturing fluid, gel breaker, and clean water are sent to the recovery device for recovery through the back pressure device.

[0006] Furthermore, the fracturing fluid in the evaluation method is guar gum fracturing fluid.

[0007] Furthermore, the fracturing fluid in the evaluation method is a cross-linked gel fracturing fluid.

[0008] Furthermore, the fracturing fluid in the evaluation method is slick water fracturing fluid.

[0009] Furthermore, the fracturing fluid in the evaluation method is a linear gel fracturing fluid.

[0010] Furthermore, in the evaluation method, the breaker is ammonium persulfate.

[0011] Furthermore, in the evaluation method, the breaker is sodium persulfate.

[0012] Compared with the prior art, the present invention has the following advantages: the comprehensive evaluation test device for fracturing fluid of the present invention adopts a displacement pump to pump the sample into the pipeline for stable flow, which better simulates the flow conditions of the actual liquid in the oil field, improves the authenticity of the test, and calculates the drag reduction rate of the fracturing fluid; the present invention adopts an intermediate container to simulate the temperature and pressure under formation conditions, and can accurately measure the gelation and gel breaking conditions of the fracturing fluid. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0014] Figure 1 It is a structural schematic diagram of the fracturing fluid evaluation device of the present invention;

[0015] Figure 2 This is a test diagram of the cross-linking condition of the fracturing fluid of the present invention;

[0016] Figure 3 is a schematic diagram of the fracturing fluid of the present invention;

[0017] Figure 4 This is a schematic diagram of the evaluation method step of the present invention: after gel breaking.

[0018] In the figure, 1. constant-speed displacement pump a; 2. constant-speed displacement pump b; 3. constant-speed displacement pump c; 4. constant-speed displacement pump d; 5. resistivity measuring device; 6. valve a; 7. valve b; 8. valve c; 9. valve d; 10. pressure gauge a; 11. pressure gauge b; 12. high- and low-temperature test chamber a; 13. intermediate container; 14. resistivity measuring device; 15. simulated pipeline; 16. camera; 17. valve e; 18. valve f; 19. valve g; 20. valve h; 21. valve i; 22. valve j; 23. high- and low-temperature test chamber b; 24. pressure gauge c; 25. trickle pipe; 26. valve k; 27. back pressure device; 28. pressure gauge d; 29. ​​valve l; 30. constant-speed displacement pump e; 31. valve m; 32. recovery device; 33. data acquisition system. DETAILED DESCRIPTION

[0019] The present invention is described in detail below by specific examples, but the scope of protection of the present invention is not limited. Unless otherwise specified, the experimental methods adopted in the present invention are all conventional methods, and the experimental equipment, materials, reagents, etc. used can be obtained from commercial channels.

[0020] Example 1

[0021] A fracturing fluid evaluation device, characterized in that it includes a constant speed displacement pump, an intermediate container 13, a high and low temperature test chamber, a resistivity measuring device 5, a trickle pipe 25, a recovery device 32, and a data acquisition system 33; wherein there are five constant speed displacement pumps, a constant speed displacement pump a1, a constant speed displacement pump b2, a constant speed displacement pump c3, and a constant speed displacement pump d4, which are connected to the intermediate container 13 placed in the high and low temperature test chamber a12 by pipelines, a valve a6 and a pressure gauge a10 are sequentially provided on the pipeline connecting the constant speed displacement pump a1 and the intermediate container 13, and a constant speed displacement pump a10 is connected to the intermediate container 13 by pipelines connecting the constant speed displacement pump a1 and the intermediate container 13. The connection line between the speed displacement pump b2 and the intermediate container 13 is provided with valves b7 and e17 in sequence. The connection line between the constant speed displacement pump c3 and the intermediate container 13 is provided with valves c8, f18 and e17 in sequence. The connection line between the constant speed displacement pump d4 and the intermediate container 13 is provided with valve d9 in sequence. The connection line between the constant speed displacement pump e30 and the back pressure device 27 is connected. The connection line between the constant speed displacement pump e30 and the back pressure device 27 is provided with valve l29 and pressure gauge d28 in sequence. The intermediate container 13 is provided with a simulation pipeline. 15, resistivity measuring device 14, camera 16 installed above resistivity measuring device 14, resistivity measuring device 14 is connected to resistivity measuring device 5 outside intermediate container 13 through a line; the pipeline above intermediate container 13 and the pipeline below intermediate container 13 are merged and connected to trickle pipe 25 placed in high and low temperature test chamber b23, valve j22 is installed on the merged line, valve h20 is installed on the pipeline above intermediate container 13, valve g19 is installed on the pipeline below intermediate container 13, the other end of trickle pipe 25 is connected to back pressure device 27, A valve k26 is provided on the connecting pipe; the back pressure device 27 is also connected to a recovery device 32, and a valve m31 is provided on the connecting pipe; a branch is also provided on the pipe above the intermediate container 13 to connect the trickle pipe 25 and the back pressure device 27, and a pressure gauge b11 and a valve i21 are provided on the branch in sequence; a pressure gauge c24 is provided at one end of the trickle pipe 25 connected to the intermediate container 13, and a branch is connected to the data acquisition system 33 at the end, and the data acquisition system 33 is also connected to the connecting pipe of the trickle pipe 25 and the back pressure device 27.

[0022] According to the evaluation method of the above-mentioned fracturing fluid evaluation device, the steps are as follows: confirm that all valves are closed, load fracturing fluid into the constant speed displacement pump b2, load gel breaker into the constant speed displacement pump c3, load clean water into the constant speed displacement pump d4, open valve e17, displace the fracturing fluid into the simulated pipeline 15 of the intermediate container 13, close valves b7 and e17, adjust the temperature and pressure of the high and low temperature test box a12 to the same formation conditions, use camera 16 to observe the fracturing fluid out of the wall of the simulated pipeline 15 and detect the resistivity of the fracturing fluid through the resistivity meter 14, transmit the resistivity data to the resistivity meter 5 for graph drawing, and determine the gel formation of the fracturing fluid through resistivity graph transformation; open valve a6 and use constant speed displacement pump a1 to adjust the annulus pressure; open valve d9, valve f18, valve g19, valve j22, pump clean water into the trickle pipe 25 through the constant speed displacement pump d4, and The acquisition system 33 measures the resistance of the clean water, closes valves d9 and f18, opens valve b7, and pumps the fracturing fluid into the trickle pipe 25 via the constant-speed displacement pump b2. The resistance is tested by the pressure difference between the two sides and the data acquisition system 33, and the resistance reduction rate is determined by the above test; close valves b7 and g19, open valves c8, e17, and f18, pump the breaker into the simulated pipe 15, observe the breakage, observe the fracturing fluid at the wall of the simulated pipe 15 via the camera 16, detect the resistivity of the fracturing fluid via the resistivity meter 14, transmit the resistivity data to the resistivity measuring device 5 for graphing, and determine the breakage of the fracturing fluid via resistivity graph transformation; open valves h20 and j22, use the constant-speed displacement pump d4 to pump out clean water to push the breakage fluid into the trickle pipe 25 to test the resistance reduction rate. The tested fracturing fluid, breaker, and clean water are sent to the recovery device 32 for recovery via the back pressure device 27.

[0023] The above-described embodiments are only preferred embodiments of the present invention, and are not intended to be all feasible embodiments of the present invention. For those skilled in the art, any obvious modifications made thereto without departing from the principles and spirit of the present invention should be considered to be included within the scope of protection of the claims of the present invention.

Claims

1. A fracturing fluid evaluation device, characterized in that: The invention comprises a constant speed displacement pump, an intermediate container (13), a high and low temperature test chamber, a resistivity measuring device (5), a trickle pipe (25), a recovery device (32), and a data acquisition system (33); wherein five constant speed displacement pumps are provided, namely, a constant speed displacement pump a (1), a constant speed displacement pump b (2), a constant speed displacement pump c (3), and a constant speed displacement pump d (4); the pipelines of the constant speed displacement pump a (1), a constant speed displacement pump b (2), a constant speed displacement pump c (3), and a constant speed displacement pump d (4) are connected to the intermediate container (13) placed in the high and low temperature test chamber a (12); a valve a (6) and a pressure gauge a (10) are provided in sequence on the pipeline connecting the constant speed displacement pump a (1) and the intermediate container (13); a valve a (6) and a pressure gauge a (10) are provided on the pipeline connecting the constant speed displacement pump b (2 ... ) connecting pipelines are provided with valves b (7) and e (17) in sequence; valves c (8), f (18) and e (17) are provided in sequence on the connecting pipelines between the constant speed displacement pump c (3) and the intermediate container (13); valves d (9) are provided in sequence on the connecting pipelines between the constant speed displacement pump d (4) and the intermediate container (13); the pipeline of the constant speed displacement pump e (30) is connected to the back pressure device (27); valves l (29) and pressure gauge d (28) are provided in sequence on the connecting pipelines between the constant speed displacement pump e (30) and the back pressure device (27); the intermediate container (13) is provided with a simulation pipeline (15), a resistor The resistivity measuring device (14) and the camera (16) are arranged above the resistivity measuring device (14). The resistivity measuring device (14) is connected to the resistivity measuring device (5) outside the intermediate container (13) through a line. The upper pipeline and the lower pipeline of the intermediate container (13) are merged and connected to the trickle pipe (25) placed in the high and low temperature test box b (23). A valve j (22) is provided on the merged line. A valve h (20) is provided on the upper pipeline of the intermediate container (13). A valve g (19) is provided on the lower pipeline of the intermediate container (13). The other end of the trickle pipe (25) is connected to the back pressure device (27). A valve k (26) is provided on the pipeline; the back pressure device (27) is further connected to a recovery device (32), and a valve m (31) is provided on the connecting pipeline; a branch is further provided on the pipeline above the intermediate container (13) to connect the trickle pipeline (25) and the back pressure device (27), and a pressure gauge b (11) and a valve i (21) are provided on the branch in sequence; a pressure gauge c (24) is provided on one end of the trickle pipeline (25) connected to the intermediate container (13), and a branch is connected to the data acquisition system (33) at the end, and the data acquisition system (33) is further connected to the connecting pipeline of the trickle pipeline (25) and the back pressure device (27).

2. The evaluation method of the fracturing fluid evaluation device according to claim 1, wherein: The steps are as follows: confirm that all valves are closed, load the constant speed displacement pump b (2) with fracturing fluid, load the constant speed displacement pump c (3) with gel breaker, load the constant speed displacement pump d (4) with clean water, open valve e (17), displace the fracturing fluid into the simulated pipe (15) of the intermediate container (13), close valve b (7) and valve e (17), adjust the temperature and pressure of the high and low temperature test box a (12) to the same formation conditions, use the camera (16) to observe the fracturing fluid flowing out of the wall of the simulated pipe (15) and the flow of the fluid through the pipe. The resistivity meter (14) detects the resistivity of the fracturing fluid, transmits the resistivity data to the resistivity measuring device (5) for graphing, and determines the gelation of the fracturing fluid by resistivity graph transformation; opens valve a (6) and uses constant speed displacement pump a (1) to adjust the annular pressure; opens valves d (9), f (18), g (19), and j (22), and pumps clean water into the trickle pipe (25) through the constant speed displacement pump d (4), and determines the pressure difference between the two sides and the data acquisition system (33). The resistance of clean water is measured by closing valves d (9) and f (18), opening valve b (7), and pumping the fracturing fluid into the trickle pipe (25) through the constant speed displacement pump b (2). The resistance is tested by the pressure difference between the two sides and the data acquisition system (33). The resistance reduction rate is determined by the above test. The valves b (7) and g (19) are closed, and valves c (8), e (17), and f (18) are opened. The gel breaker is pumped into the simulated pipe (15), and the gel breaking situation is observed. The simulation is observed through the camera (16). The fracturing fluid condition at the wall of the simulated pipeline (15) is detected by a resistivity meter (14), and the resistivity data is transmitted to a resistivity measuring device (5) for graphing. The gel breaking condition of the fracturing fluid is determined by resistivity graph transformation. The valves h (20) and j (22) are opened, and the constant speed displacement pump d (4) is used to pump out clean water to push the gel breaking fluid into the trickle pipe (25) to test the resistance reduction rate. The fracturing fluid, gel breaker, and clean water after the test are sent to the recovery device (32) for recovery through the back pressure device (27).

3. The evaluation method of the fracturing fluid evaluation device according to claim 2, characterized in that: The fracturing fluid is guar gum fracturing fluid.

4. The evaluation method of the fracturing fluid evaluation device according to claim 2, characterized in that: The fracturing fluid is a cross-linked gel fracturing fluid.

5. The evaluation method of the fracturing fluid evaluation device according to claim 2, characterized in that: The fracturing fluid is slick water fracturing fluid.

6. The evaluation method of the fracturing fluid evaluation device according to claim 2, characterized in that: The fracturing fluid is a linear gel fracturing fluid.

7. The evaluation method of the fracturing fluid evaluation device according to claim 2, characterized in that: The gel breaker is ammonium persulfate.

8. The evaluation method of the fracturing fluid evaluation device according to claim 2, characterized in that: The gel breaker is sodium persulfate.

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