Bubble generating mechanism, micro-nano bubble host comprising same and application of bubble generating mechanism in processing technology of photovoltaic cell

Abstract

The invention discloses a bubble generating mechanism, a micro-nano bubble host comprising the bubble generating mechanism and application of the bubble generating mechanism in the processing technology of photovoltaic cells. The bubble generating mechanism comprises an outer shell and an inner shell which are sleeved with each other, a liquid flow channel allowing liquid to flow through is formed in the middle of the inner shell and comprises a first flow channel, a throat part and a second flow channel, and the end, close to the second end, of the first flow channel is connected with the throat part; the inner diameter of the throat portion does not exceed the inner diameter of the end, close to the second end, of the first flow channel, the inner diameter of the second flow channel is gradually increased in the direction close to the second end, the inner surface of the second flow channel is a smooth wall face, the air inlet flow channel communicates with the liquid flow channel in the circumferential direction, and the air inlet flow channel communicates with the throat portion in the circumferential direction. And the inner surface of at least partial area of the first flow channel is a spiral flow channel. The bubble generating mechanism can ensure that the generated micro-nano bubbles are smaller in particle size and more stable.

Description

Bubble generating mechanism, its micro / nano-scale bubble generator, and its application in photovoltaic cell processing. Technical Field

[0001] This invention relates to the field of nanobubble preparation technology, specifically to a bubble generating mechanism, a micro / nano-scale bubble generator containing the bubble, and its application in the processing technology of photovoltaic cells. Background Technology

[0002] Most existing bubble generating mechanisms achieve air mixing by introducing air into liquid channels of equal diameter. However, this often results in insufficient mixing of air with liquid and fails to guarantee the formation of stable micro- and nano-sized bubbles.

[0003] In addition, a common problem with existing nanobubble generation mechanisms is that after forming micro- and nanobubbles, they cannot remain stable for a long time, and the bubbles may even burst inside the bubble generator, resulting in poor bubble stability. Summary of the Invention

[0004] To overcome the above-mentioned shortcomings, the present invention aims to provide a bubble generating mechanism, including an outer shell and an inner shell, wherein the inner shell is fitted inside the outer shell, a first end of the inner shell is a liquid inlet, a second end is a liquid outlet, a liquid flow channel is provided in the middle of the inner shell for liquid to flow through, the liquid flow channel includes a first flow channel, a throat and a second flow channel arranged sequentially from the first end to the second end, the first flow channel is provided in at least a portion of the inner shell near the liquid inlet, the inner diameter of the first flow channel gradually decreases towards the second end, the end of the first flow channel near the second end is connected to the throat, and the inner diameter of the throat does not exceed the inner diameter of the end of the first flow channel near the second end, the inner diameter of the second flow channel gradually increases towards the second end, the inner surface of the second flow channel is a smooth wall surface, the bubble generating mechanism also includes an air inlet channel communicating with the liquid flow channel, the air inlet channel communicating with the throat in the circumferential direction, and the inner surface of at least a portion of the first flow channel is a spiral flow channel.

[0005] The present invention has the following beneficial effects: ① By setting the liquid flow channel to have the smallest inner diameter at the throat, and setting the first flow channel and the second flow channel to gradually increase the inner diameter in the direction away from the throat, the inner diameter at the throat is the smallest, thus forming a negative pressure at the throat and efficiently drawing in air, so as to ensure the air mixing effect without applying any external pressure.

[0006] ② By setting the first flow channel as a spiral flow channel and the second flow channel as a smooth wall, the liquid entering the liquid flow channel maintains a spiral flow direction, thus effectively extending the contact time between air and liquid, allowing air to mix with liquid repeatedly, thereby achieving the effect of fully dispersing bubbles. Setting the inner surface of the second flow channel as a smooth wall can reduce excessive turbulence or shearing of the liquid caused by the internal structure of the liquid flow channel, ensuring the stability of the generated micro-nano bubbles.

[0007] ③ By connecting the air intake channel and the throat in the circumferential direction, it is possible to ensure that the airflow that can enter the throat region enters evenly, and there will be no single or uneven air intake area formed only in the local air intake area. Therefore, it is possible to ensure that the air intake volume and air intake uniformity that can enter the throat are high, thereby making the generated micro-nano-scale bubbles stable.

[0008] Furthermore, an air inlet is provided on the outer casing, which is connected to the air intake channel. A guide groove, recessed towards its central axis, is provided on the outer surface of the inner casing, and is connected to the air inlet. Therefore, the guide groove distributes the air entering through the air inlet, ensuring that the air enters the air intake channel evenly.

[0009] Furthermore, a first sealing assembly is provided between the outer shell and the inner shell. The first sealing assembly is disposed adjacent to the flow guide groove and is located on both sides of the flow guide groove near the first end and the second end, respectively. Therefore, it can be ensured that the air entering through the air inlet is sufficiently restricted and guided into the liquid flow channel.

[0010] Furthermore, the inner shell includes a first structural member and a second structural member. The first structural member has a first structural surface, and the second structural member has a second structural surface. The first and second structural surfaces are truncated conical surfaces that can fit together, forming the air intake channel between the first and second structural surfaces. Therefore, the air intake channel formed by the gap between the first and second structural members ensures uniform air intake.

[0011] Furthermore, the throat includes at least two throat regions with different inner diameters, and the inner diameter of the throat gradually increases from the first end to the second end. By providing at least two throat regions and setting the inner diameter of the throat to gradually increase towards the second end, it is ensured that outside air is fully drawn into the throat, and that the resistance when the gas-liquid mixture enters the second flow channel from the throat is low, thus maintaining the vortex force on the liquid flow.

[0012] Furthermore, at least a portion of the inner surface of the throat is also provided with a spiral flow channel. Therefore, after the gas mixes with the liquid, the liquid still maintains sufficient vortex force, allowing for thorough gas-liquid mixing.

[0013] Furthermore, it also includes a first end cap located near the first end and a second end cap located near the second end. The first and second end caps are detachably connected to the outer casing, and both ends of the inner casing abut against the first and second end caps, respectively. This structure facilitates the assembly of the bubble generating mechanism.

[0014] Furthermore, a snap-fit ​​flange is provided on the inner surface of the outer casing near the first and second ends, and snap-fit ​​grooves are provided on the first and second end caps to engage with the snap-fit ​​flanges. This facilitates the connection and disconnection of the outer casing from the first and second end caps.

[0015] The present invention also provides a micro / nano-scale bubble generator comprising the aforementioned bubble generating mechanism. The micro / nano-scale bubble generator of the present invention ensures the generation of bubbles with smaller particle sizes and greater stability.

[0016] The present invention also provides an application of the aforementioned bubble generating mechanism or micro / nano-scale bubble generator in wafer cleaning equipment or silicon rod cutting equipment.

[0017] The present invention also provides a photovoltaic cell processing system, which includes at least one of the aforementioned bubble generating mechanisms or the aforementioned micro-nano bubble generator.

[0018] This invention also provides a photovoltaic cell processing technology, comprising at least one of the following steps: a silicon rod bonding and fixing step; a silicon rod cutting step; a silicon wafer debinding and cleaning step; and a texturing step. At least one of the silicon rod cutting step, silicon wafer debinding and cleaning step, and texturing step is implemented using the aforementioned bubble generating mechanism or the aforementioned micro / nano-scale bubble generator. Because the photovoltaic cell processing technology of this invention employs a generator capable of producing stable micro / nano-scale bubbles with smaller particle sizes, it achieves higher processing efficiency for the cells and effectively reduces the amount of chemical reagents used. This further reduces processing costs and subsequent wastewater treatment costs.

[0019] This invention also provides an application of the aforementioned bubble generating mechanism or the aforementioned micro / nano-scale bubble generator in machining processes. In some embodiments, it can be used in the cleaning or cooling stages of machining, or in the application of lubricants, etc. Attached Figure Description

[0020] Figure 1 is a three-dimensional structural schematic diagram of a bubble generating mechanism according to an embodiment of the present invention; Figure 2 is a cross-sectional structural schematic diagram of a bubble generating mechanism according to an embodiment of the present invention; Figure 3 is a partially enlarged schematic diagram of point A in Figure 2; Figure 4 is a partially enlarged schematic diagram of point B in Figure 2; Figure 5 is a schematic diagram of a throat region having two or more different inner diameters; Figure 6 is a three-dimensional structural schematic diagram of a micro-nano-scale bubble generator according to an embodiment of the present invention; Figure 7 is a three-dimensional structural schematic diagram of a micro-nano-scale bubble generator according to another perspective of an embodiment of the present invention; Figure 8 is a three-dimensional structural schematic diagram of a micro-nano-scale bubble generator according to another perspective of an embodiment of the present invention. In the diagram: 1. Outer shell; 11. Air inlet; 12. Snap-fit ​​flange; 2. Inner shell; 21. Liquid inlet; 22. Liquid outlet; 23. Liquid flow channel; 231. First flow channel; 232. Throat; 2321. Throat region; 233. Second flow channel; 234. First end; 235. Second end; 24. Guide groove; 3. Inlet air channel; 31. First structural component; 311. First structural surface; 32. Second structural component; 321. Second structural surface; 41. First sealing assembly; 42. Second sealing assembly; 51. First end cap; 52. Second end cap; 511. Snap-fit ​​groove; 512. Limiting platform; 6. Filter section; 61. First filter tank; 62. ... 7. Filter tank; 8. Cooling section; 9. Booster pump; 10. Bubble generating mechanism; 111. Stabilizing tank; 112. First conveying pipe; 113. Second conveying pipe; 114. Third conveying pipe; 115. Fourth conveying pipe; 116. Liquid inlet pipe; 117. Liquid outlet pipe; 1181. First horizontal section; 1182. Vertical section; 1183. Second horizontal section; 1184. Liquid outlet; 121. First pressure sensor; 122. Second pressure sensor; 123. Third pressure sensor; 124. Fourth pressure sensor; 125. Fifth pressure sensor; 126. Sixth pressure sensor; 127. Seventh pressure sensor; 13. Temperature sensor. Detailed Implementation

[0021] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0022] Example 1: This example is a bubble generating mechanism 9, which includes an outer shell 1 and an inner shell 2 that are nested together and coaxially arranged. The first end 234 of the inner shell 2 is a liquid inlet 21, and the second end 235 is a liquid outlet 22. A liquid flow channel 23 for liquid to flow through is provided in the middle of the inner shell 2.

[0023] The liquid flow channel 23 includes a first flow channel 231, a throat 232, and a second flow channel 233 arranged sequentially from a first end 234 to a second end 235. The first flow channel 231 is located in at least a portion of the inner shell 2 near the liquid inlet 21. The inner diameter of the first flow channel 231 gradually decreases towards the second end 235. The end of the first flow channel 231 near the second end 235 is connected to the throat 232, and the inner diameter of the throat 232 does not exceed the inner diameter of the end of the first flow channel 231 near the second end 235. The inner surface of at least a portion of the first flow channel 231 is a spiral flow channel. The inner diameter of the second flow channel 233 gradually increases towards the second end 235, and the inner surface of the second flow channel 233 is a smooth wall. The bubble generating mechanism 9 also includes an inlet flow channel 3 connected to the liquid flow channel 23, and one end of the inlet flow channel 3 is located near the throat 232. The inlet channel 3 is circumferentially connected to the throat 232, thus ensuring that the airflow entering the throat 232 can uniformly enter the bubble generating mechanism. This stable air supply maximizes the stability of the subsequently generated micro- and nano-sized bubbles from the initial stage of bubble generation. At least a portion of the inner surface of the first channel 231 is a spiral channel. This allows the liquid to be guided in a spiral shape within the liquid channel 23, significantly extending the residence time of the liquid within the bubble generating mechanism 9. This effectively increases the contact time with air and allows the liquid mixed with air to be fully sheared in the second channel 233, effectively dispersing the bubbles into nano-sized particles.

[0024] During bubble generation, the liquid first flows in through the first channel 231 and then flows out through the second channel 233 after passing through the throat 232. Since the inner diameter is smallest at the throat 232, according to the principle of the Venturi tube, the liquid velocity increases and the pressure decreases at the throat 232, i.e., below atmospheric pressure. Therefore, the maximum air intake effect can be achieved at the throat 232. As the liquid mixed with air continues to enter the second liquid channel 23, it maintains a spiral rotation under the guidance of the first channel, thus greatly increasing the mixing time between the air and liquid within the liquid channel 23, achieving the effect of fully dispersing the bubbles. Furthermore, because the inner surface of the first channel 231 is smooth, excessive turbulence or shearing of the liquid caused by the internal structure of the channel can be minimized after the micro-nano bubbles have formed, ensuring the high stability of the generated micro-nano bubbles.

[0025] In some embodiments, the throat 232 includes at least two throat regions 2321 (not shown in the figure) with different inner diameters, and the inner diameter of the throat 232 gradually increases in the direction from the first end 234 to the second end 235. For example, the different throat regions 2321 can be arranged in a stepped manner, such as setting the inner diameter of the same throat region 2321 to be the same, and setting the inner diameter of the throat region 2321 near the second end 235 to be larger than the inner diameter of the throat region 2321 near the first end 234. The number of throat regions 2321 can also be set to two, three or more as needed. Alternatively, the inner diameter of the same throat region 2321 can be set to the form of a truncated cone (as shown in Figure 5), as long as the inner diameter of the throat 232 as a whole gradually increases in the direction from the first end 234 to the second end 235. By setting at least two throat regions 2321 and setting the inner diameter of the throat 232 to gradually increase towards the second end 235, it is possible to ensure that outside air is fully drawn into the throat 232 and that the gas-liquid mixture has low resistance when entering the second flow channel 233 from the throat 232, thus fully maintaining the vortex force on the liquid flow.

[0026] In some embodiments, at least a portion of the inner surface of the throat 232 is also provided with a spiral flow channel. In some embodiments, the spiral flow channel of the throat 232 may be provided in a manner connected to the spiral flow channel of the first flow channel 231, so that the liquid flow maintains a spiral direction. In other possible embodiments, the spiral flow channel may be provided only in the middle of the throat 232 or near the second end 235, thereby enabling the liquid to produce a flow direction enhancement effect in the throat 232.

[0027] In some embodiments, an air inlet 11 is provided on the outer shell 1, and an air intake channel 3 is provided in the inner shell 2. Thus, outside air can flow through the air inlet 11, through the air intake channel 3, and into the liquid flow channel 23.

[0028] In some embodiments, the air intake channel 3 of the inner shell 2 is formed by a first structural surface 311 and a second structural surface 321. Correspondingly, the inner shell 2 can be configured as a first structural member 31 and a second structural member 32, with the first structural surface 311 and the second structural surface 321 located on the first structural member 31 and the second structural member 32, respectively, and arranged opposite to each other. The first structural surface 311 and the second structural surface 321 are configured as truncated conical surfaces, thus allowing the first structural member 31 and the second structural member 32 to be interlocked, and the air intake channel 3 is formed at the first structural surface 311 and the second structural surface 321 between them. In some embodiments, the first structural surface 311 and the second structural surface 321 are arranged in a direction that gradually inclines towards the central axis of the throat 232, thereby enabling the air intake channel 3 to guide the air entering the liquid flow channel 23 along the direction of liquid flow.

[0029] In some embodiments, a guide groove 24 recessed towards its central axis is provided on the outer surface of the inner shell 2. The guide groove 24 is arranged circumferentially around the outer surface of the inner shell 2. The guide groove 24 is connected to the air inlet 11 of the outer shell 1 and is located approximately at the same position in the axial direction of the bubble generating mechanism 9. Therefore, the air entering through the air inlet 11 can enter the guide groove 24 and be evenly distributed around the air intake channel, ensuring a stable air source and airflow.

[0030] In some embodiments, one end of the air intake passage 3 is located at the end of the throat 232 near the first end 234. This allows outside air to be fully drawn into the throat 232 and to have maximum contact with the liquid.

[0031] In some embodiments, the liquid flows in a spiral direction within the liquid channel 23, with the central axis of the liquid channel 23 as the axis. Therefore, the residence time of the liquid within the liquid channel 23 is prolonged under the influence of the spiral flow, thereby increasing the opportunity for contact with air and extending the contact time with air. This allows the liquid in the second channel 233 to be repeatedly abraded and mixed with air, thus achieving optimal bubble formation. For example, the inner wall of the first channel 231 can be shaped as a cone or a spiral, as long as the thread size gradually decreases towards the second end 235.

[0032] In some embodiments, a first sealing assembly 41 is further provided between the outer shell 1 and the inner shell 2. The first sealing assembly 41 is disposed adjacent to the guide groove 24 and is located on both sides of the guide groove 24 near the first end 234 and the second end 235, respectively. Therefore, it can be ensured that the air entering through the air inlet 11 is sufficiently restricted and guided into the liquid flow channel 23.

[0033] In some embodiments, a first end cap 51 is provided near the first end 234, and a second end cap 52 is provided near the second end 235. The first end cap 51 and the second end cap 52 are detachably connected to the outer shell 1, and the two ends of the inner shell 2 abut against the first end cap 51 and the second end cap 52, respectively. A snap-fit ​​flange 12 protruding outwards away from the central axis is provided on the inner surface of the outer shell 1 near the first end 234 and the second end 235, respectively. Snap-fit ​​grooves 511 that engage with the snap-fit ​​flanges 12 are provided on the first end cap 51 and the second end cap 52, respectively. A limiting platform 512 that abuts against the edge of the inner shell 2 is also provided on the first end cap 51 and the second end cap 52, thus enabling a secure connection between the outer shell 1 and the inner shell 2. In some embodiments, a second sealing assembly 42 is provided between the snap-fit ​​flange 12 and the snap-fit ​​groove 511 and the end edge of the outer shell 1, thus effectively ensuring the connection between the first end cap 51 and the second end cap 52 and the outer shell 1.

[0034] Example 2: Referring to Figures 6-8, this example is a micro-nano bubble generator, which includes the bubble generating mechanism 9 of Example 1.

[0035] In some embodiments, the micro-nano bubble generator of the present invention includes a filter section 6, a cooling section 7, a booster pump 8, a bubble generating mechanism 9, and a stabilizing tank 10 arranged sequentially.

[0036] In some embodiments, the filter section 6 includes a first filter tank 61 and a second filter tank 62. The second filter tank 62 is located on the side of the first filter tank 61 away from the cooling section 7, so that a relatively long first conveying pipe 111 can be formed between the second filter tank 62 and the cooling section 7. A flow meter is installed on the first conveying pipe 111. By installing a flow meter on this relatively long first conveying pipe 111, the accuracy of the flow monitoring results can be ensured.

[0037] The liquid flow path of the micro / nano-scale bubble generator of the present invention is as follows: it flows in through the inlet pipe 115 from the side wall near the top of the first filter tank 61, then flows out through the side wall near the bottom of the first filter tank 61 and flows in through the side wall near the bottom of the second filter tank 62, and then flows out through the side wall near the top of the second filter tank 62. It then flows into the cooling section 7, which has a hot water inlet connected to the first delivery pipe 111 and a hot water outlet connected to the booster pump 8. A second delivery pipe 112 is provided between the hot water outlet and the booster pump 8. A third delivery pipe 113 is provided between the booster pump 8 and the bubble generating mechanism 9. A fourth delivery pipe 114 is provided between the bubble generating mechanism 9 and the stabilizing tank 10. Both the third and fourth delivery pipes 113 and 114 are located below the stabilizing tank 10, thus making the appearance of the micro / nano-scale bubble generator more visually simple. Liquid containing air bubbles enters the stabilizing tank 10 from its bottom and exits through a drain pipe 116 located on the side wall near the top of the stabilizing tank 10. The drain pipe 116 includes a first horizontal section 1161, a vertical section 1162, and a second horizontal section 1163. A drain port 1164 is located at the end of the second horizontal section 1163, and the height of the drain port 1164 is lower than the height of the inlet. This pipe arrangement creates a stable flow rate between the first horizontal section 1161 and the second horizontal section 1163, maximizing the stability of air bubbles in the liquid discharged from the stabilizing tank 10.

[0038] In some embodiments, the booster pump 8 is used to pressurize the liquid entering the bubble generating mechanism 9. The pressure inside the stabilizing tank 10 is lower than the pressure of the booster pump 8, but still greater than one standard atmosphere. Therefore, it can degas excess large bubbles generated during the bubble generation process, resulting in a higher proportion of micro / nano bubbles in the liquid. The stabilizing tank 10 is under positive pressure. In some embodiments, the pressure inside the stabilizing tank 10 is approximately 70% of the pressure set in the booster pump 8. For example, if the pressure set in the booster pump 8 is 2 MPa, then the pressure inside the stabilizing tank 10 is 1.4 MPa.

[0039] In some embodiments, a pressure regulating valve is installed upstream of the bubble generating mechanism 9 (liquid inlet). For example, a diaphragm pressure regulating valve can be used, with an adjustment accuracy of ±0.05MPa, which can automatically compensate for the pressure according to the liquid inlet pressure (compensation range is 0.1-2.0MPa).

[0040] In some implementations, an emergency pressure relief valve is installed downstream of the bubble generating mechanism 9 (liquid outlet 22). For example, a spring-loaded pressure relief valve can be used, with a set pressure of 1.1-1.2 times the system operating pressure. When the pressure exceeds the limit, it automatically opens to relieve pressure within 150ms. The pressure relief port is connected to a safety recovery pipeline to prevent reagent leakage.

[0041] In some embodiments, the micro / nano-scale bubble generator of the present invention further includes a pressure feedback system, which includes multiple pressure sensors disposed on the liquid delivery pipeline and a control system connected to the pressure sensors. In some embodiments, the pressure sensors have a measurement range of 0-3 MPa, a response time of ≤30 ms, and the data they collect is transmitted to the control system in real time. When the pressure fluctuation exceeds ±5%, the opening of the pressure regulating valve is automatically adjusted.

[0042] In some embodiments, the pressure sensors of the pressure feedback system include: a first pressure sensor 121 near the inlet of the first filter tank 61; a second pressure sensor 122 located between the first filter tank 61 and the second filter tank 62; a third pressure sensor 123 near the outlet of the second filter tank 62; a fourth pressure sensor 124 located near the outlet of the cooling section; a fifth pressure sensor 125 near the inlet of the bubble generating mechanism 9; a sixth pressure sensor 126 near the inlet of the stabilizing tank 10; and a seventh pressure sensor 127 located in the vertical section 1162 of the drain pipe 116. This arrangement of pressure sensors allows for real-time monitoring of the pressure in various areas of the system, ensuring that the bubble generating mechanism 9 produces stable and controllable bubbles. In particular, the placement of the first pressure sensor 121, the second pressure sensor 122, and the third pressure sensor 123 enables stable and real-time monitoring of the pressure of the liquid before and after passing through the filter section 6, which may significantly affect the liquid pressure. The fourth pressure sensor 124 can monitor the pressure of the cooled water in a timely manner, preventing any abnormalities in the cooling section from affecting the subsequent bubble generation effect. The fifth pressure sensor 125 and the sixth pressure sensor 126 can monitor the pressure of the liquid before and after entering the bubble generating mechanism 9 in real time. By placing the seventh pressure sensor 127 in the vertical section 1162 instead of the first horizontal section 1161 or the second horizontal section 1163, effective monitoring of the pressure in the drain pipe 116 can be ensured.

[0043] In some embodiments, the micro / nano-scale bubble generator of the present invention further includes a plurality of temperature sensors 13. The area where the temperature sensors 13 are installed can coincide with the area where the pressure sensors are installed, and the number of temperature sensors 13 can be the same as the number of pressure sensors. The pressure sensors are connected to the pipe through a T-junction, while the temperature sensors 13 extend directly into the pipe. The T-junction and the temperature sensors 13 can be arranged opposite each other on both sides of the pipe. In other possible embodiments, temperature sensors 13 may be installed only in some of the pressure sensor installation areas, that is, the number of temperature sensors 13 is less than the number of pressure sensors. For example, the installation of temperature sensors 13 in the installation areas of the second pressure sensor 122, the fourth pressure sensor 124, and the seventh pressure sensor 127 can be omitted.

[0044] The micro-nano bubble generator of the present invention minimizes the damage to bubbles caused by the internal structure of the bubble generating mechanism by controlling the stability of the gas source and forming bubbles in the bubble generating mechanism. At the same time, the voltage stabilization system and the layout of each mechanism of the micro-nano bubble generator effectively reduce the damage to bubbles caused by pipeline transportation, etc., thus enabling the bubbles generated by the generator to have high stability and a higher proportion of nano-sized bubbles.

[0045] The bubble size and distribution, as well as operating parameters such as pressure and temperature, generated by the micro / nano-scale bubble generator of this invention were compared with those of existing bubble generators. Bubble size and distribution were measured using a nanoparticle tracking analyzer (NTA), with samples taken every 5-10 minutes, and the average value of 3-5 measurements was taken. Operating parameters such as pressure and temperature were collected in real time by the system's built-in sensors, with a data sampling frequency of 0.5-1Hz. All data are statistical results from 2-3 different models of generators and 8-12 batches of experiments, as shown in Table 1.

[0046] Table 1. Comparison of bubble size and distribution between the bubble generators of this application and existing technologies.

[0047] As shown in Table 1, the bubble generator of this application produces smaller bubble particles with a particle size increase of only 25% within 15 minutes, resulting in better stability. Furthermore, the bubble particle size distribution produced by the bubble generator of this application is more concentrated, thus effectively avoiding impact damage caused by the rupture of large bubbles. The bubble concentration produced by the bubble generator of this application is also higher, thus exhibiting stronger impurity adsorption capacity.

[0048] Example 3: This example describes a photovoltaic cell processing system that utilizes the micro / nano-scale bubble cleaning unit from Example 2 to clean photovoltaic silicon wafers. The drain pipe of the bubble cleaning unit is connected to a water tank for cleaning the silicon wafers, and the water in the tank is circulated through the micro / nano-scale bubble cleaning unit. After continuous operation for 8-48 hours, the liquid is replaced. The cleaning time and cleaning agent dosage are compared, and the results are shown in Table 2.

[0049] Table 2 Comparison of the effects of this application and existing technologies in silicon wafer cleaning

[0050] Therefore, the photovoltaic cell processing system of the present invention has lower requirements for water temperature, thus effectively reducing the overall energy consumption requirements of the system. Furthermore, the system of the present invention produces uniform bubbles, resulting in higher cleaning efficiency for silicon wafers, thereby effectively reducing production costs. In addition, traditional silicon wafer cleaning processes mostly require the use of composite cleaning agents, which are costly, while the present application only requires a single cleaning agent to achieve the cleaning effect, thus further reducing wastewater treatment costs.

[0051] In other possible implementations, the micro / nano-scale bubble generator of Example 2 can also be used to cut the silicon rod, and diamond wire can be used to cut the silicon rod. To avoid silicon rod residue remaining on the diamond wire affecting the cutting effect, during cutting, the bubble water generated by the micro / nano-scale bubble generator is directly sprayed into the area where the diamond wire is located (for example, forming a fan-shaped or umbrella-shaped spray area). In other possible implementations, the bubble water can also be sprinkled from the overflow tank onto the diamond wire. The removal rate of particulate impurities generated during cutting is determined by the dry weighing method, that is, the weight difference obtained by weighing a certain amount of cleaning solution and drying it is the weight of the particulate impurities. Metal residue is measured using X-ray fluorescence spectrometry. The metal residue index reflects the weight of metal that has been deposited in the pipeline or reaction system and adhered to the surface of the silicon wafer. The cutting effects are compared, and the results are shown in Table 3.

[0052] Table 3 Comparison of the effects of this application and existing technologies in silicon rod cutting.

[0053] As shown in Table 3, the particulate impurity removal rate of this application is significantly improved. Furthermore, by reducing the amount of chemicals used and utilizing micro-nano bubble water, the amount of metal residue on the silicon wafer surface is effectively reduced, and the cutting yield is also improved. Since the processing system of this application can effectively separate the generated silicon powder dust from the diamond wire during silicon rod cutting, dust in the cutting chamber can be further reduced. This application directly uses the cutting fluid as the water source for the entire cleaning system of the machine chamber, integrating the cutting and cleaning processes into one step, saving water and improving efficiency. In contrast, the existing technology requires 1-2 hours to clean the cutting chamber after each cutting operation.

[0054] In other possible implementations, the micro / nano-scale bubble generator of Example 2 can also be used for degumming. Before cutting the silicon wafer, the silicon rod needs to be adhered and fixed to the fixture; therefore, after cutting, residual adhesive on its surface needs to be degummed using a lactic acid solution. Using the micro / nano-scale bubble generator of the present invention can reduce the concentration and amount of lactic acid (degumming agent).

[0055] In other possible implementations, the micro-nano bubble generator of Example 2 can also be used in the texturing stage of photovoltaic cells. By using the microbubbles generated by the micro-nano bubble generator of the present invention, the concentration of acid solutions (such as HF and / or HNO3) used in the texturing stage can be reduced.

[0056] Example 4: This example is a machining equipment that utilizes the micro-nano-level bubble generator from Example 2 for cleaning machined parts or products. Using this equipment can effectively reduce the amount of chemical cleaning agents and solvents used, lowering production costs and also reducing wastewater treatment costs. In other possible implementations, the machining equipment in this example utilizes the micro-nano-level bubble generator from Example 2 for cooling during the machining process. By using bubbles generated by the bubble generator, the surface tension of cooling media such as cutting fluid can be reduced, making it easier for them to penetrate into hard-to-reach areas between the workpiece and the tool. This more effectively removes cutting heat, reduces the temperature of the tool and workpiece, reduces thermal deformation, and improves machining accuracy and surface quality.

[0057] In other possible implementations, the machining equipment of this embodiment utilizes the micro-nano bubble host of Embodiment 2 to apply lubricant during the machining process. Under the action of microbubbles, the lubricant can be more evenly distributed in the machining area, forming a more stable lubricating film, effectively reducing friction between the tool and the workpiece, reducing tool wear, increasing tool life, and thus improving machining efficiency and surface finish.

[0058] The above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable those skilled in the art to understand the content of the present invention and implement it. They should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A bubble generating mechanism, comprising an outer shell, characterized in that, Also includes: An inner shell is fitted inside the outer shell. The inner shell has a first end as a liquid inlet and a second end as a liquid outlet. A liquid flow channel is provided in the middle of the inner shell for liquid to flow through. The liquid flow channel includes a first flow channel, a throat, and a second flow channel arranged sequentially from the first end to the second end. The first flow channel is located in at least a portion of the inner shell near the liquid inlet. The inner diameter of the first flow channel gradually decreases towards the second end. The end of the first flow channel near the second end is connected to the throat, and the inner diameter of the throat does not exceed the inner diameter of the end of the first flow channel near the second end. The inner diameter of the second flow channel gradually increases towards the second end. The inner surface of the second flow channel is a smooth wall. The bubble generating mechanism also includes an air inlet channel connected to the liquid flow channel. The air inlet channel is circumferentially connected to the throat. The inner surface of at least a portion of the first flow channel is a spiral flow channel.

2. The bubble generating mechanism according to claim 1, characterized in that, An air inlet is provided on the outer shell, and the air inlet is connected to the air intake channel. A guide groove is provided on the outer surface of the inner shell, which is recessed towards its central axis and is connected to the air inlet.

3. The bubble generating mechanism according to claim 2, characterized in that, A first sealing assembly is also provided between the outer shell and the inner shell. The first sealing assembly is disposed adjacent to the guide channel and is located on both sides of the guide channel near the first end and the second end, respectively.

4. The bubble generating mechanism according to claim 1, characterized in that, The inner shell includes a first structural member and a second structural member. The first structural member has a first structural surface, and the second structural member has a second structural surface. The first and second structural surfaces are truncated conical surfaces that can fit together, and the air intake channel is formed between the first and second structural surfaces.

5. The bubble generating mechanism according to claim 1, characterized in that, The throat includes at least two throat regions with different inner diameters, and the inner diameter of the throat gradually increases along the direction from the first end to the second end.

6. The bubble generating mechanism according to claim 1, characterized in that, At least a portion of the inner surface of the throat is also provided with a spiral flow channel.

7. The bubble generating mechanism according to any one of claims 1-6, characterized in that, It also includes a first end cap disposed near the first end and a second end cap disposed near the second end, the first end cap and the second end cap being detachably connected to the outer shell, and the two ends of the inner shell respectively abutting against the first end cap and the second end cap.

8. The bubble generating mechanism according to claim 7, characterized in that, A snap-fit ​​flange is provided on the inner surface of the outer casing near the first end and the second end, and a snap-fit ​​groove is provided on the first end cover and the second end cover to engage with the snap-fit ​​flange.

9. A micro / nano-scale bubble generator, characterized in that, It includes the bubble generating mechanism according to any one of claims 1-8.

10. The application of the bubble generating mechanism according to any one of claims 1-8 or the micro / nano-scale bubble generator according to claim 9 in wafer cleaning equipment or silicon rod cutting equipment.

11. A photovoltaic cell processing system, characterized in that, It includes at least one bubble generating mechanism as described in any one of claims 1-8 or the micro / nano-scale bubble generator as described in claim 7.

12. A processing technology for photovoltaic cells, characterized in that, The device includes at least one of the following steps: silicon rod bonding and fixing step; silicon rod cutting step; silicon wafer debonding and cleaning step; and texturing step, wherein at least one of the silicon rod cutting step, silicon wafer debonding and cleaning step, and texturing step is implemented using the bubble generating mechanism according to any one of claims 1-8 or the micro-nano bubble generator according to claim 7.

13. The application of the bubble generating mechanism according to any one of claims 1-8 or the micro / nano-scale bubble generator according to claim 9 in the machining process.

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