High pressure foam forming device and method based on a tesla valve

Abstract

This invention discloses a high-pressure foam forming device based on Tesla valves, including a generating chamber with a foam discharge hole at the upper end and a liquid injection valve and a gas injection valve at the lower end. The generating chamber contains several Tesla valves connected end-to-end. Each Tesla valve has a filter screen at both its upper and lower ends, and each Tesla valve is equipped with a liquid injection valve and a gas injection valve. The liquid injection valve and gas injection valve are intermittently connected to the main / branch flow channels of the Tesla valves. The invention also discloses a method for using the device. This invention is applicable to the field of oil and gas field development technology. Based on the foam working pressure requirements and referring to the indicator diagram, it can generate a relatively stable foam system under various pressure environments. The connection method is simple, the operation is convenient, and it comprehensively meets the experimental requirements under various pressures.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas field development technology, specifically a high-pressure foam forming device and method based on Tesla valves. Background Technology

[0002] Most oilfields in China have entered the high water-cut or even ultra-high water-cut development stage. Improving the remaining oil recovery rate at this stage is crucial for enhancing the overall development efficiency of the oilfields. Foam flooding, due to its low implementation cost, relatively simple process, and significant effect on improving oil recovery (generally increasing recovery by 10%–25%), is widely used in oilfields and is currently an effective measure to improve development efficiency in the high water-cut stage and enhance crude oil recovery after polymer flooding.

[0003] A foam generator is a device that introduces gas into a foaming agent solution, and the two are thoroughly mixed to produce foam. Foam stability is an important criterion for evaluating the performance of a foam generator. The paper "A Visualized High-Temperature and High-Pressure In-Situ Foam Generator and Method" (CN114112855A) discloses a method for visualizing a high-temperature and high-pressure foam generator; however, this device requires confining pressure to increase its pressure resistance, making operation less convenient and faster when changing experimental pressures. The paper "A Foam Generator for High-Temperature and High-Pressure Micro-Reaction Displacement Experiments" (CN113738321A) discloses a method for high-temperature and high-pressure micro-reaction experiments; however, the foam generation structure of this device uses a traditional direct-flow structure, which cannot prevent liquid backflow to a certain extent.

[0004] Currently, laboratory foam generators cannot stably produce foam in simulated high-pressure (over 30 MPa) environments. Therefore, it is necessary to invent a device that can stably produce foam under high-pressure conditions for foam operation. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a high-pressure foam forming apparatus and method based on a Tesla valve.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] Firstly, a high-pressure foam forming device based on Tesla valves includes a device generating chamber, with a foam discharge hole at the upper end of the device generating chamber, and a liquid injection valve and an air injection valve at the lower end of the device generating chamber. The device generating chamber is equipped with several Tesla valves connected end to end. Each Tesla valve is equipped with a filter screen at both the upper and lower ends, and each Tesla valve is equipped with a liquid injection valve and an air injection valve. The liquid injection valve and the air injection valve are all connected at intervals to the main / branch flow channels of the Tesla valve.

[0008] Preferably, the θ angle of the Tesla valve is 30° to 60°.

[0009] Preferably, the θ angle of the Tesla valve is 45°.

[0010] Preferably, the bottom of the generating chamber of the device is provided with a triangular support, which is mounted on the base.

[0011] Preferably, the top of the generating chamber of the device is provided with a sealing cover for sealing the generating chamber, and the vent hole passes through the sealing cover.

[0012] Preferably, the total number of liquid injection valves and gas injection valves is 16 to 24.

[0013] Preferably, the total number of liquid injection valves and air injection valves is 20.

[0014] Preferably, the mesh size of the filter is 15 to 35 mesh.

[0015] Preferably, the mesh size of the filter is 25 mesh.

[0016] Secondly, a high-pressure foam formation method based on Tesla valves includes the following steps:

[0017] Step 1: Determine the position of the injection valve using the indicator panel based on the foam working pressure;

[0018] Step 2: Determine the position of the air injection valve based on the indicator panel according to the working pressure of the foam;

[0019] Step 3: Connect the gas and liquid supply sources and start injecting gas and liquid fluids to produce working foam.

[0020] Preferably, in step 1, the indicator plate marks the critical pressure for the presence of foam corresponding to any liquid injection valve and any gas injection valve, with the x-coordinate being the liquid injection valve number, the y-coordinate being the gas injection valve number, and the z-coordinate being the critical pressure for the presence of foam.

[0021] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0022] In this invention, a relatively stable foam system can be generated under various pressure environments based on the foam working pressure requirement reference diagram. The connection method is simple, the operation is convenient, and it comprehensively meets the experimental requirements under various pressures. Among them, the Tesla valve in the device cavity can increase the resistance to liquid backflow, thereby greatly preventing liquid backflow from affecting the foaming effect of the device when the pressure at the device outlet is high. At the same time, vortices can be formed in the Tesla valve channel, making the gas-liquid mixture more uniform and helping to generate bubbles. Moreover, a filter screen is installed in the Tesla valve channel in the device cavity, eliminating the need for stirring to generate foam. Under the background condition that the Tesla valve can generate vortices in the channel, the problems of insufficient and uneven foaming are further avoided. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of the high-pressure foam forming device based on Tesla valves according to the present invention;

[0024] Figure 2 This is a cross-sectional view of the high-pressure foam forming device based on the Tesla valve of the present invention;

[0025] Figure 3 This is a schematic diagram of the Tesla valve structure in this invention;

[0026] Figure 4 This is a schematic diagram of the filter structure in this invention;

[0027] Figure 5 This is a schematic diagram of the indicator plate in this invention.

[0028] Reference numerals: A1: Exhaust hole; A2: Sealing cap; A3: Valve; A4: Triangular support; A5: Generating chamber of the device; A6: Base; B2: Filter screen; Y1~Y9: Liquid injection valve; Y10: No. 1 liquid injection valve; Q1~Q9: Gas injection valve; Q10: No. 1 gas injection valve. Detailed Implementation

[0029] The following embodiments further illustrate specific implementations of the high-pressure foam forming apparatus and method based on Tesla valves of the present invention. The high-pressure foam forming apparatus and method based on Tesla valves of the present invention are not limited to the descriptions in the following embodiments.

[0030] Example 1:

[0031] High-pressure foam forming device based on Tesla valve, such as Figure 1-4 As shown, a high-pressure foam forming device based on a Tesla valve, such as Figure 1-5As shown, the device includes a generating chamber A5, with a defoaming hole A1 at the upper end of the generating chamber A5, and a liquid injection valve Y10 and a gas injection valve Q10 at the lower end of the generating chamber A5. The generating chamber A5 is equipped with several Tesla valves connected end to end. Each Tesla valve has a filter screen B2 at both the upper and lower ends. Each Tesla valve is equipped with a liquid injection valve and a gas injection valve. The liquid injection valve and the gas injection valve are connected to the main / branch flow channels of the Tesla valve at intervals.

[0032] Furthermore, the θ angle of the Tesla valve is 30°.

[0033] Furthermore, a triangular bracket A4 is provided at the bottom of the generating chamber A5 of the device, and the triangular bracket A4 is located on the base A6.

[0034] Furthermore, a sealing cover A2 is provided on the top of the generating chamber A5 of the device to seal the chamber body of the generating chamber A5, and the vent hole A1 passes through the sealing cover A2.

[0035] Furthermore, the total number of liquid injection valves and gas injection valves is 16.

[0036] Furthermore, the mesh size of filter B2 is 15 mesh.

[0037] Example 2:

[0038] High-pressure foam forming device based on Tesla valve, such as Figure 1-4 As shown, a high-pressure foam forming device based on a Tesla valve, such as Figure 1-5 As shown, the device includes a generating chamber A5, with a defoaming hole A1 at the upper end of the generating chamber A5, and a liquid injection valve Y10 and a gas injection valve Q10 at the lower end of the generating chamber A5. The generating chamber A5 is equipped with several Tesla valves connected end to end. Each Tesla valve has a filter screen B2 at both the upper and lower ends. Each Tesla valve is equipped with a liquid injection valve and a gas injection valve. The liquid injection valve and the gas injection valve are connected to the main / branch flow channels of the Tesla valve at intervals.

[0039] Among them, the Tesla valve in the generating chamber A5 of the device can increase the resistance to liquid backflow, thereby greatly preventing liquid backflow from affecting the foaming effect of the device when the pressure at the outlet end of the device is high.

[0040] A vortex can be formed in the Tesla valve channel within the generating chamber A5 of the device, making the gas-liquid mixture more uniform and facilitating the generation of bubbles.

[0041] Furthermore, the θ angle of the Tesla valve is 45°.

[0042] Furthermore, a triangular bracket A4 is provided at the bottom of the generating chamber A5 of the device, and the triangular bracket A4 is located on the base A6.

[0043] Furthermore, a sealing cover A2 is provided on the top of the generating chamber A5 of the device to seal the chamber body of the generating chamber A5, and the vent hole A1 passes through the sealing cover A2.

[0044] It is worth noting that the valves can be directly connected after referring to the instruction diagram according to the work requirements. The connection method is simple, the operation is convenient, and it comprehensively meets the experimental needs under various pressures. The pressure range that can be simulated varies depending on the number of injection valves designed. Considering both the simulable pressure range and cost, the pressure range that can be simulated with different numbers of valves is shown in Table 1:

[0045] Table 1 shows the pressure range that can be simulated with the number of valves.

[0046] valve / unit 2 4 6 8 10 12 Pressure / MPa 0～0.1 0～0.5 0～1.1 0～4.3 0～15.5 0～37. valve / unit 14 16 18 20 22 24 Pressure / MPa 0～55.4 0～73.6 0～84.3 0～99.6 0～103.5 0～105.1

[0047] It can be seen that when there are fewer than 20 valves, the pressure range is too small and there is still room for improvement. When there are more than 20 injection valves, the pressure range that can be increased is not significant. Therefore, the optimal design is 20 injection valves to adapt to different experimental pressures.

[0048] A filter screen is installed inside the Tesla valve channel within the device cavity, eliminating the need for stirring to generate foam. This further avoids insufficient and uneven foaming, especially given the potential for eddy currents generated by the Tesla valve within the channel. A foam generator was used to evaluate the foam volume of the foaming agent at the same concentration passing through filters of different mesh sizes at a 1:1 gas-liquid ratio. The results are shown in Table 2. Ultimately, a 25-mesh filter was selected, as it produced the largest foam volume and achieved the best effect.

[0049] Table 2. Foaming volume at different mesh sizes

[0050] Filter mesh count / mesh 10 15 20 25 30 35 foaming volume / mL 213 248 276 317 304 296

[0051] Example 3:

[0052] High-pressure foam forming device based on Tesla valve, such as Figure 1-4 As shown, a high-pressure foam forming device based on a Tesla valve, such as Figure 1-5 As shown, the device includes a generating chamber A5, with a defoaming hole A1 at the upper end of the generating chamber A5, and a liquid injection valve Y10 and a gas injection valve Q10 at the lower end of the generating chamber A5. The generating chamber A5 is equipped with several Tesla valves connected end to end. Each Tesla valve has a filter screen B2 at both the upper and lower ends. Each Tesla valve is equipped with a liquid injection valve and a gas injection valve. The liquid injection valve and the gas injection valve are connected to the main / branch flow channels of the Tesla valve at intervals.

[0053] Furthermore, the θ angle of the Tesla valve is 60°.

[0054] Furthermore, a triangular bracket A4 is provided at the bottom of the generating chamber A5 of the device, and the triangular bracket A4 is located on the base A6.

[0055] Furthermore, a sealing cover A2 is provided on the top of the generating chamber A5 of the device to seal the chamber body of the generating chamber A5, and the vent hole A1 passes through the sealing cover A2.

[0056] Furthermore, the total number of liquid injection valves and gas injection valves is 24.

[0057] Furthermore, the mesh size of filter B2 is 35 mesh.

[0058] Experimental Example 1:

[0059] To verify the optimal selection of the characteristic angle θ of the Tesla valve in the high-pressure foam forming device based on the Tesla valve, the ADINA software was used to simulate the forward and reverse flow effects when the characteristic angle θ is changed, that is, to perform a simulation analysis of pressure and flow velocity.

[0060] When θ = 30°, the pressure drop at the inlet and outlet is 4.32 * 10⁴ for forward flow and 5.17 * 10⁴ for reverse flow. 4 .

[0061] When θ = 45°, the pressure drop at the inlet and outlet is 4.96 * 10⁴ for forward flow and 5.81 * 10⁴ for reverse flow. 4 .

[0062] When θ = 60°, the pressure drop at the inlet and outlet is 5.53 × 10⁴ for forward flow and 6.25 × 10⁴ for reverse flow. 4 .

[0063] In summary, when θ = 30°, the reverse resistance is not significant; when θ = 60°, the reverse resistance is the greatest, the ability to prevent backflow is the strongest, but the forward conduction ability is weakened. Therefore, an inclination angle of θ = 45° is chosen.

[0064] Example 4:

[0065] A high-pressure foam formation method based on Tesla valves includes the following steps:

[0066] Step 1: Determine the position of the injection valve using the indicator panel based on the foam working pressure;

[0067] Step 2: Determine the position of the air injection valve based on the indicator panel according to the working pressure of the foam;

[0068] Step 3: Connect the gas and liquid supply sources and start injecting gas and liquid fluids to produce working foam.

[0069] Furthermore, in step 1, the indicator panel shows the critical pressure for the presence of foam corresponding to any liquid injection valve and any gas injection valve. Its x-coordinate is the liquid injection valve number, y-coordinate is the gas injection valve number, and z-coordinate is the critical pressure for the presence of foam.

[0070] Furthermore, the indicator board structure is as follows: Figure 5 As shown in the figure, the parameters are shown in Table 3:

[0071] Table 3: Figure 5 parameters

[0072]

[0073] Example 5:

[0074] Taking the X37 fault block reservoir in Shengli Oilfield as an example, the X37 fault block is a typical complex fault block reservoir with multiple oil layers, medium porosity, medium to high permeability, normal temperature and pressure, weak edge water, and thin oil. Addressing the problem of uneven water flow in high-water-cut complex fault block reservoirs and the difficulty in improving the efficiency of conventional waterflooding, a foam-based controlled-flow technology is proposed. This technology selectively blocks and inhibits water channeling and high-permeability layers, temporarily plugs and changes the direction of fluid flow, expands the waterflood reach, improves oil displacement efficiency, and further enhances reservoir recovery.

[0075] The geological reserves of the X37 fault block are 441 × 10⁻⁶. 4 The parameters are: t, permeability 438 mD, porosity 24%, original formation pressure 27.2 MPa, and foam working pressure requirement 28 MPa. Therefore, the use of this device will be described in detail based on 28 MPa.

[0076] Step 1: Determine the position of the injection valve based on the foam working pressure using the indicator diagram. For example, if the experiment requires a foam working pressure of 28 MPa, referring to the gas-liquid connection position indicator diagram, select injection valve Y5.

[0077] Step 2: Determine the position of the air injection valve based on the foam working pressure using the indicator chart. According to the gas-liquid connection position indicator chart, the air injection valve is Q8. At this point, the maximum critical pressure of the foam is 28.23 MPa, which meets the experimental pressure requirements.

[0078] Step 3: Connect the gas and liquid supply sources and begin injection. Connect the foaming agent solution to valve Y5 and the gas source to valve Q8. Close other gas injection valves and liquid injection valves. Open valves Q8 and Y5 to simultaneously inject gas and foaming agent solution into device cavity A5. The gas and foaming agent solution flow through the Tesla valve flow channel B1 within the cavity and generate foam through filter screen B2. The foam pressure between multiple filters is progressively superimposed, ensuring that the foam remains relatively stable under high pressure conditions, meeting the foam working conditions at the target pressure.

[0079] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A high-pressure foam forming device based on a Tesla valve, characterized in that: The device includes a generating chamber (A5), with a defoaming hole (A1) at the upper end and a liquid injection valve (Y10) and a gas injection valve (Q10) at the lower end. The generating chamber (A5) is equipped with several Tesla valves connected end to end. Each Tesla valve has a filter screen (B2) at both the upper and lower ends. Each Tesla valve is equipped with a liquid injection valve and a gas injection valve, which are spaced apart and connected to the main / branch flow channels of the Tesla valve.

2. The high-pressure foam forming apparatus based on a Tesla valve as described in claim 1, characterized in that: The θ angle of the Tesla valve is 30° to 60°.

3. The high-pressure foam forming apparatus based on a Tesla valve as described in claim 1, characterized in that: The θ angle of the Tesla valve is 45°.

4. The high-pressure foam forming apparatus based on a Tesla valve as described in claim 1, characterized in that: The device has a triangular support (A4) at the bottom of the generating chamber (A5), and the triangular support (A4) is mounted on the base (A6).

5. The high-pressure foam forming apparatus based on a Tesla valve as described in claim 1, characterized in that: The device generating chamber (A5) is provided with a sealing cover (A2) at the top for sealing the chamber (A5), and the vent hole (A1) passes through the sealing cover (A2).

6. The high-pressure foam forming apparatus based on a Tesla valve as described in claim 1, characterized in that: The total number of liquid injection valves and gas injection valves is 16 to 24.

7. The high-pressure foam forming apparatus based on a Tesla valve as described in claim 1, characterized in that: The total number of liquid injection valves and gas injection valves is 20.

8. The high-pressure foam forming apparatus based on a Tesla valve as described in claim 1, characterized in that: The filter screen (B2) has a mesh size of 15 to 35.

9. The high-pressure foam forming apparatus based on a Tesla valve as described in claim 1, characterized in that: The filter (B2) has a mesh size of 25.

10. A high-pressure foam formation method based on a Tesla valve, characterized in that, Includes the following steps: Step 1: Determine the position of the injection valve using the indicator panel based on the foam working pressure; Step 2: Determine the position of the air injection valve based on the indicator panel according to the working pressure of the foam; Step 3: Connect the gas and liquid supply sources and start injecting gas and liquid fluids to produce working foam.

11. The high-pressure foam formation method based on a Tesla valve as described in claim 10, characterized in that: In step 1, the indicator board shows the critical pressure for the presence of foam corresponding to any liquid injection valve and any gas injection valve. Its x-coordinate is the liquid injection valve number, y-coordinate is the gas injection valve number, and z-coordinate is the critical pressure for the presence of foam.

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