Hydrodynamic cavitation spray head and spray cleaning system

Abstract

The utility model discloses a hydrodynamic cavitation spray head and a spray cleaning system, and relates to the field of hydrodynamic cavitation for cleaning and oil removal. The hydrodynamic cavitation spray head comprises a first cavitation generator and a spray head body, the first cavitation generator comprises a vortex cavity, the vortex cavity comprises a top face, a wall face and a bottom face, a wall face included angle is formed between the bottom face and the wall face, and the wall face included angle ranges from 120 degrees to 180 degrees; the liquid inlet pipe is obliquely arranged in the vortex cavity and is communicated with the vortex cavity; the included angle between the central axis of the liquid inlet pipe and the central axis of the vortex cavity is 45-90 degrees; the liquid outlet pipe is inserted into the vortex cavity and comprises an inner diameter contraction section, an inner diameter expansion section and an inner diameter invariable section in the liquid outlet direction; a nozzle is arranged at one end of the spray head, and the other end of the spray head is detachably connected with the liquid outlet pipe. The spray cleaning system comprises a hydrodynamic cavitation nozzle and a cleaning tank, a storage rack is arranged in the cleaning tank, the storage rack is of a hollow structure, and a filtrate layer is arranged below the storage rack; and the hydrodynamic cavitation nozzle is arranged above or on the side surface of the cleaning tank. The utility model provides a hydrodynamic cavitation nozzle and a cavitation spray cleaning system, which greatly improve the cleaning capacity, are low in energy consumption and reduce the discharge amount of cleaning wastewater.

Description

Technical Field

[0001] This utility model relates to the field of cleaning oily workpieces, and more particularly to the application of hydraulic cavitation in cleaning and oil removal. Background Technology

[0002] In the manufacturing industry, rolled steel plates and metal parts need to be cleaned before assembly and packaging. The main targets of cleaning are residual coolant, sealing oil, and metal chips and shavings generated during processing. The purpose of cleaning is to remove contaminants from the surface of parts without damaging the metal surface, within a specified time, using the appropriate equipment and cleaning medium. Cleaning is also an important pretreatment step before processes such as painting, electroplating, and heat treatment. The quality of cleaning directly affects the processing performance and overall performance of mechanical products.

[0003] The cleaning process generally includes chemical cleaning, primary water rinsing, acid pickling, and secondary water rinsing. Chemical cleaning and primary water rinsing are used to remove grease from steel plates and parts. Chemical cleaning typically uses alkaline cleaning agents. Traditionally, this step involves immersion or water jetting, which are inefficient, require large amounts of cleaning agents, and generate significant wastewater. To reduce cleaning agent and water consumption, ultrasonic cleaning has been researched and applied in cleaning lines. Ultrasonic cleaning utilizes the cavitation phenomenon generated by the action of particles at a frequency of 20-30 kHz in water. This causes intense motion and impact between liquid particles, impacting contaminants on the workpiece surface, dispersing them into the liquid. Simultaneously, the intense particle motion emulsifies two immiscible liquids (such as water and oil), accelerating the dissolution of contaminants. Therefore, ultrasonic cleaning also enhances the cleaning effect of cleaning agents. However, ultrasonic cavitation only occurs near the ultrasonic probe, the amount of ultrasonic cavitation generated is limited, and the energy utilization rate is low, with an energy conversion efficiency of only 5-10%. The remaining 90-95% is dissipated as heat, which is the biggest limitation restricting its large-scale industrial application.

[0004] Currently, the most common methods for treating steel rolling mill cleaning water are air flotation for oil removal and membrane separation technology, such as ultrafiltration. Both of these methods require the addition of appropriate water treatment agents, such as demulsifiers and flocculants. Adding these agents results in the separated cleaning fluid being unrecoverable, and the treatment cost is high. Another method uses filtration and oil-water separation, but ordinary oil-water separation can only remove floating oil from the surface of the cleaning water, not emulsified oil or oil-in-water emulsions, leading to incomplete removal of impurities and the inability to recycle the cleaning fluid. Summary of the Invention

[0005] To address the existing problem of cleaning oily workpieces, this invention provides a hydraulic cavitation nozzle and a cavitation spray cleaning system, which greatly improves cleaning capacity, has low energy consumption, allows for the recycling of cleaning fluid, and reduces the discharge of cleaning wastewater.

[0006] Based on the above-mentioned technical problems, the technical solution of this utility model is as follows:

[0007] A hydraulic cavitation nozzle includes a first cavitation generator and a nozzle, wherein the first cavitation generator includes:

[0008] The vortex cavity includes a top surface, a wall surface, and a bottom surface, wherein the bottom surface and the wall surface form a wall angle of 120 to 180 degrees.

[0009] An inlet pipe is inclinedly disposed in the vortex cavity and communicates with the vortex cavity; the angle between the central axis of the inlet pipe and the central axis of the vortex cavity is 45 to 90 degrees.

[0010] The liquid outlet pipe is inserted into the vortex cavity and, along the liquid outlet direction, includes an inner diameter contraction section, an inner diameter diffusion section, and an inner diameter constant section;

[0011] One end of the nozzle is equipped with a nozzle, and the other end is detachably connected to the liquid outlet pipe.

[0012] Preferably, the liquid outlet pipe has an inner diameter increasing section, and the outlet of the inner diameter increasing section has a threaded connection hole; the nozzle has an external thread that mates with the threaded connection hole.

[0013] A spray cleaning system includes a hydraulic cavitation nozzle; the spray cleaning system also includes a cleaning tank, a shelf inside the cleaning tank, the shelf having a hollow structure, and a liquid storage layer below the shelf; the hydraulic cavitation nozzle is disposed above or on the side of the cleaning tank.

[0014] Preferably, the liquid storage layer is connected to a demulsifier tank, the demulsifier tank is connected to a hydraulic cavitation module, and the hydraulic cavitation module includes a second high-pressure pump and a second cavitation generator connected in sequence.

[0015] Preferably, the demulsifying tank is also provided with a clean water inlet and a cleaning agent inlet; the demulsifying tank is provided with an overflow baffle, which separates the demulsifying tank into an oil collection tank.

[0016] Preferably, the demulsifying tank is connected to the hydraulic cavitation nozzle; a precision filter and a first high-pressure pump are connected between the demulsifying tank and the hydraulic cavitation nozzle.

[0017] Preferably, the spray cleaning system further includes a settling tank, the demulsification tank is connected to the settling tank, the liquid surface of the settling tank is provided with a floating liquid suction port, and the floating liquid suction port is connected to a floating oil separation device.

[0018] Preferably, the second high-pressure pump is connected to the demulsifying tank, and the outlet pipe of the second cavitation generator is connected to the demulsifying tank and the settling tank respectively through valves; the settling tank is connected to the hydraulic cavitation nozzle.

[0019] Preferably, an inlet pump and a pre-filter are connected between the liquid storage layer and the demulsification tank.

[0020] Compared with the prior art, the beneficial technical effects of this utility model are as follows:

[0021] 1. The hydraulic cavitation nozzle, which combines a vortex-type hydraulic cavitation generator with a nozzle, generates a hydraulic cavitation effect when the liquid flow first passes through a fluid vortex and then through the inner diameter contraction section, throat, and inner diameter diffusion section. This forms a nanoscale gas-liquid mixed microjet. The mechanical effect generated by the cavitation microjet and the huge impact force of the fluid medium can reduce the surface tension of the cleaning fluid and increase the cleaning capacity. Moreover, the huge energy released when the cavitation bubbles generated by hydraulic cavitation collapse generate heat, which enhances the ability to remove oil stains.

[0022] 2. The huge impact force released when the cavitation bubble collapses is applied to the surface of the oil-stained workpiece, which has a shot peening effect on the workpiece, and can remove part of the oxide scale on the workpiece surface, reducing the pressure of subsequent acid and water washing.

[0023] 3. The cleaning solution after spray cleaning is introduced into the demulsification tank for further hydraulic cavitation treatment, which breaks the oil-in-water emulsion in the cleaning solution into floating oil. Then, through oil-water separation, the floating oil is removed, and the cleaning solution is recycled, which improves the utilization rate of the cleaning solution and reduces the amount of cleaning wastewater discharged.

[0024] 4. Compared with general cleaning or ultrasonic cleaning methods, this spray cleaning system has lower energy consumption; several sets of hydraulic cavitation nozzles are set at different work stations (such as chemical cleaning station and water washing station), which greatly improves cleaning efficiency. Attached Figure Description

[0025] Figure 1 This utility model provides a structural schematic diagram of a hydraulic cavitation nozzle.

[0026] Figure 2 This is a cross-sectional view of a hydraulic cavitation nozzle according to the present invention.

[0027] Figure 3 This is a system flow diagram of the spray cleaning system in Example 1.

[0028] Figure 4 This is a schematic diagram of the side installation of a hydraulic cavitation nozzle.

[0029] Figure 5 The system flow diagram for implementing the spray cleaning system in step 2.

[0030] Figure 6 This is a top view of the spray cleaning tank.

[0031] In the diagram: 1. Hydraulic cavitation nozzle, 100. First cavitation generator, 101. Liquid outlet pipe, 102. Liquid inlet pipe, 103. Vortex chamber, 1030. Top surface, 1031. Bottom surface, 1032. Cleaning tank, 20. Oil-stained workpiece, 20. Nozzle, 201. Shelf, 21. Liquid storage layer, 22. Cover plate, 23. Pre-filter, 3. Demulsification tank, 4. Clean water inlet, 40. Cleaning agent inlet, 41. Oil collection tank, 42. Overflow baffle, 43. Settling tank, 5. Clean water inlet, 50. Cleaning agent inlet, 51. Second cavitation generator, 6. Second high-pressure pump, 7. First high-pressure pump, 8. Floating oil separation device, 9. Floating suction port, 90. Precision filter, 10. Detailed Implementation

[0032] The present invention will be further described below with reference to the accompanying drawings and specific embodiments:

[0033] like Figure 1 , Figure 2 A hydraulic cavitation nozzle includes a first cavitation generator 100 and a nozzle 200. The first cavitation generator is a miniaturized cavitation generator, such as... Figure 2 The miniaturized cavitation generator includes a vortex cavity 103, an inlet pipe 102, and an outlet pipe 101. The vortex cavity 103 includes a top surface 1030, a wall surface 1031, and a bottom surface 1032. The bottom surface 1032 and the wall surface 1031 form a wall angle of 120 to 180 degrees. The height of the top and bottom surfaces of the vortex cavity 103 is the height of the vortex cavity, which is 10 to 30 mm. The inlet pipe 102 is inclinedly disposed outside the vortex cavity 103. The inlet pipe 102 and the vortex cavity 103 are connected. The central axis of the inlet pipe 102 and the central axis of the vortex cavity 103 form an angle of 45-90 degrees. The outlet pipe 101 is inserted into the vortex cavity 103 and is coaxially arranged with the vortex cavity 103. Along the liquid outlet direction, it includes an inner diameter contraction section, an inner diameter diffusion section, and an inner diameter constant section. An inner diameter expansion section is provided at the outlet of the outlet pipe, and a threaded connection hole is provided at the outlet of the inner diameter expansion section. One end of the nozzle 200 has an external thread that mates with the threaded connection hole, and the other end of the nozzle has a nozzle 201. The outlet pipe 101 is connected to the nozzle 200. The cavitation generator is a one-piece molded structure and can be formed by injection molding or 3D printing. Injection molding only incurs mold opening costs, and subsequent mass production is possible. The cost of the cavitation generator is relatively lower than that of metal processing and forming. The nozzle can be various water outlet shapes available on the market, such as cylindrical, fan-shaped, conical, and atomizing nozzles.

[0034] Example 1:

[0035] like Figure 3A spray cleaning system includes a hydraulic cavitation nozzle 1 and a cleaning tank 2. The hydraulic cavitation nozzle 1 is located above the cleaning tank 2. A shelf 21 is provided inside the cleaning tank 2. The shelf 21 has a hollow structure and a liquid storage layer 22 is provided below the shelf 21. Oily workpieces 20 to be cleaned are placed on the shelf 21.

[0036] like Figure 3 The liquid storage layer 22 is connected to the demulsification tank 4, and the demulsification tank 4 is connected to the hydraulic cavitation module. The hydraulic cavitation module includes a second high-pressure pump 7 and a second cavitation generator 6 connected in sequence. The outlet pipe of the second cavitation generator 6 is connected to one side of the demulsification tank 4, and the second high-pressure pump 7 is connected to the other side of the demulsification tank 4. The demulsification tank 4 is also provided with a clean water inlet 40 and a cleaning agent inlet 41. The clean water inlet 40 can be filled with pure water or tap water.

[0037] The demulsification tank 4 is also equipped with an overflow baffle 43, which separates the demulsification tank 4 into an oil collection tank 42. The oil collection tank 4 is located on the opposite side of the liquid outlet of the hydraulic cavitation module. The liquid outlet of the second cavitation generator 6 pushes the surface floating oil towards the oil collection tank 42. The demulsification tank 4 is connected to the hydraulic cavitation nozzle 1, and a precision filter 10 and a first high-pressure pump 8 are connected between the demulsification tank 4 and the hydraulic cavitation nozzle 1. The cleaning solution after demulsification and oil removal is then injected into the hydraulic cavitation nozzle 1 to clean the oil-containing workpiece 20 to be cleaned.

[0038] An inlet pump and a pre-filter 3 are provided between the liquid storage layer 22 and the demulsification tank 4. The pre-filter can filter out large particles entering the demulsification tank 4 to prevent blockage or damage to the second cavitation generator 6.

[0039] like Figure 4 If the cleaning tank 2 is relatively deep, or if the oily workpiece 20 to be cleaned has a large placement height, a hydraulic cavitation nozzle 1 can be installed on the side wall of the cleaning tank.

[0040] like Figure 6 To improve cleaning efficiency, several hydraulic cavitation nozzles 1 can be distributed above the cleaning tank 2. Depending on the width and length of the cleaning tank, several groups of hydraulic cavitation nozzles 1 can be arranged. A cover plate 23 is also provided on the outside of the hydraulic cavitation nozzles 1 to prevent water mist from splashing out. Oily workpieces 20 are placed on top of a shelf and can also be transported from one cleaning station to the next via a conveyor belt or chain conveyor, such as from a chemical cleaning station to a primary water washing station (not shown in the figure). Several groups of hydraulic cavitation nozzles 1 are installed at both the chemical cleaning station and the primary water washing station.

[0041] If the chemical washing station is in operation, a cleaning agent or degreaser needs to be added to the demulsification tank 4; if the primary water washing station is in operation, no cleaning agent or degreaser needs to be added to the demulsification tank 4, only pure water or tap water is required.

[0042] The working principle of the spray cleaning system in Example 1:

[0043] like Figure 3 Oil-contaminated workpieces 20 are transferred to the chemical cleaning station. Hydraulic cavitation nozzles 1, located above or to the side of the cleaning tank 2, spray and rinse the oil-contaminated workpieces 20. The oil-contaminated workpieces 20 can be rolled steel plates, metal parts, etc. The hydraulic cavitation nozzles 1 combine a vortex cavitation generator with the nozzle. The cleaning fluid or water pressurized by the first high-pressure pump 8 generates cavitation bubbles as it passes through the nozzle, which are then sprayed onto the surface of the rolled steel plate or metal parts along with the water flow, effectively cleaning them and removing oil and metal debris. The micro-jet and powerful impact generated by the hydraulic cavitation effect also have a certain removal effect on oxide scale and rust on the rolled steel plate, reducing the pressure of subsequent acid and secondary water washing.

[0044] After rinsing, the cleaning fluid enters the storage layer. The fluid in the storage layer is filtered by the pre-filter 3 and then introduced into the demulsification tank 4. In the demulsification tank 4, it undergoes hydraulic cavitation treatment by the second cavitation generator 6 to further remove the oil-in-water emulsion from the cleaning fluid, causing the oil-in-water emulsion to break down into floating oil. The floating oil is collected by the oil collection tank 42 and then discharged into an oil drum (not shown in the figure). The cleaning fluid in the demulsification tank 4 is filtered by the precision filter 10 and then pressurized by the second high-pressure pump 8, pumping it to the hydraulic cavitation nozzle 1 for continued spray cleaning of the oil-contaminated workpiece 20.

[0045] Example 2:

[0046] like Figure 5 The spray cleaning system also includes a settling tank 5, a demulsification tank 4 connected to the settling tank 5, a clean water inlet 50, and a cleaning agent inlet 51, all located on the settling tank 5. An overflow baffle can be installed inside the settling tank 5 to collect floating oil into an oil collection tank, or the surface floating oil can be removed by an oil removal mechanism (not shown in the figure). Alternatively, a floating suction port 90 can be provided on the liquid surface of the settling tank 5, and the floating suction port 90 is connected to an oil separation device 9.

[0047] The settling tank 5 is connected to the hydraulic cavitation nozzle 1, the settling tank 5 and the hydraulic cavitation nozzle 1 are connected to a precision filter 10, and the precision filter 10 and the hydraulic cavitation nozzle 1 are connected to a first high-pressure pump 8.

[0048] The demulsifying tank 4 is connected to the hydraulic cavitation module, which includes a second high-pressure pump 7 and a second cavitation generator 6 connected in sequence. The second high-pressure pump 7 is connected to the demulsifying tank 4, and the outlet pipe of the second cavitation generator 6 is connected to the demulsifying tank 4 and the settling tank 5 through valves respectively.

[0049] The operation mode of the spray cleaning system in Example 2:

[0050] like Figure 5 After rinsing, the cleaning fluid enters the storage layer. The fluid in the storage layer is filtered by the pre-filter 3 and then introduced into the demulsification tank 4. In the demulsification tank 4, it undergoes hydraulic cavitation treatment by the second cavitation generator 6 to further remove the oil-in-water emulsion from the cleaning fluid. This cavitation treatment is repeated several times in the demulsification tank 4. The outlet flow path of the hydraulic cavitation module is then switched to the settling tank 5 via a valve, and the cavitated fluid is introduced into the settling tank 5. In the settling tank 5, the fluid settles and separates into layers. The floating oil rises to the surface and is collected through an oil removal mechanism or a floating suction port for further oil-liquid separation. The treated cleaning fluid is then introduced into the hydraulic cavitation nozzle 1 for continued spray cleaning of oil-contaminated workpieces.

[0051] The present invention also aims to provide a spray cleaning method for implementing the above-mentioned spray cleaning system, the spray cleaning method comprising:

[0052] S1. The cleaning solution is used to perform hydraulic cavitation spray cleaning on the oily workpiece to be cleaned. After the cleaning solution is sprayed, it enters the storage layer. The oily workpiece is sprayed and rinsed using hydraulic cavitation nozzles above or on the side wall of the cleaning tank.

[0053] S2. The cleaning fluid in the storage layer is filtered by a pre-filter and then introduced into a demulsification tank. In the demulsification tank, hydraulic cavitation is performed, and the oil-in-water emulsion in the cleaning fluid is broken out and becomes floating oil, which is collected. The hydraulic cavitation module performs cavitation treatment on the settling tank. After several rounds of hydraulic cavitation, the treated cleaning fluid is introduced into the settling tank. Oil-liquid separation occurs in the cleaning fluid in the settling tank. The floating oil on the surface is removed by the oil removal mechanism or collected by the floating oil suction port and introduced into the floating oil separation device for further oil-liquid separation.

[0054] S3. The cleaning fluid, from which impurities and particulate matter have been separated, is directed to the hydraulic cavitation nozzle for continued spray cleaning.

[0055] The above are merely specific embodiments of this utility model, but the technical features of this utility model are not limited thereto. Any simple changes, equivalent substitutions, or modifications made based on this utility model to solve essentially the same technical problems and achieve essentially the same technical effects are all covered within the protection scope of this utility model.

Claims

1. A hydraulic cavitation nozzle, characterized in that, Includes a first cavitation generator and a nozzle, wherein the first cavitation generator includes: The vortex cavity includes a top surface, a wall surface, and a bottom surface, wherein the bottom surface and the wall surface form a wall angle of 120 to 180 degrees. An inlet pipe is inclinedly disposed in the vortex cavity and communicates with the vortex cavity; the angle between the central axis of the inlet pipe and the central axis of the vortex cavity is 45 to 90 degrees. The liquid outlet pipe is inserted into the vortex cavity and, along the liquid outlet direction, includes an inner diameter contraction section, an inner diameter diffusion section, and an inner diameter constant section; One end of the nozzle is equipped with a nozzle, and the other end is detachably connected to the liquid outlet pipe.

2. The hydraulic cavitation nozzle according to claim 1, characterized in that, The liquid outlet pipe has an inner diameter expansion section, and the outlet of the inner diameter expansion section has a threaded connection hole; the nozzle has an external thread that mates with the threaded connection hole.

3. A spray cleaning system, characterized in that, The system includes a hydraulic cavitation nozzle according to claim 1; the spray cleaning system further includes a cleaning tank, a shelf inside the cleaning tank, the shelf having a hollow structure, and a liquid storage layer below the shelf; the hydraulic cavitation nozzle is disposed above or on the side of the cleaning tank.

4. The spray cleaning system according to claim 3, characterized in that, The liquid storage layer is connected to the demulsification tank, the demulsification tank is connected to the hydraulic cavitation module, and the hydraulic cavitation module includes a second high-pressure pump and a second cavitation generator connected in sequence.

5. A spray cleaning system according to claim 4, characterized in that, The demulsification tank is also equipped with a clean water inlet and a cleaning agent inlet; the demulsification tank is equipped with an overflow baffle, which separates the demulsification tank into an oil collection tank.

6. A spray cleaning system according to claim 4, characterized in that, The demulsifying tank is connected to the hydraulic cavitation nozzle; a precision filter and a first high-pressure pump are connected between the demulsifying tank and the hydraulic cavitation nozzle.

7. A spray cleaning system according to claim 4, characterized in that, The spray cleaning system also includes a settling tank, the demulsification tank is connected to the settling tank, the liquid surface of the settling tank is provided with a floating liquid suction port, and the floating liquid suction port is connected to a floating oil separation device.

8. A spray cleaning system according to claim 4, characterized in that, The second high-pressure pump is connected to the demulsifying tank, and the outlet pipe of the second cavitation generator is connected to the demulsifying tank and the settling tank through valves respectively; the settling tank is connected to the hydraulic cavitation nozzle.

9. A spray cleaning system according to claim 4, characterized in that, The liquid storage layer is connected to the demulsification tank by an inlet pump and a pre-filter.

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