A slit-type micro-nano bubble generator

Abstract

The present invention provides a slit-type micro-nano bubble generator, comprising a main body and a pressure plate. The main body is a polyhedron, with a gas-liquid mixing device mounted on at least one face of the polyhedron, and the remaining end faces of the polyhedron serving as water outlets. A main flow channel and secondary flow channels are provided within the main body. The main flow channel communicates with the inlet of the gas-liquid mixing device, and each of the main flow channels communicates with the water outlets via a plurality of secondary flow channels. A turbulent flow chamber is formed between the water outlet of each main body and the pressure plate via a flow channel assembly for producing and outputting nanobubbles. This invention offers advantages such as a simple device structure, low cost, small bubble size, long duration, and high oxygen dissolution efficiency.

Description

Technical Field

[0001] The invention relates to the field of oxygen-enhanced irrigation, and in particular to a slit-type micro-nano bubble generator. Background Art

[0002] Agricultural water resources in my country are becoming increasingly scarce. Micro-irrigation technologies, such as subsurface drip irrigation, can significantly improve agricultural water efficiency and are an important means of addressing this shortage. However, micro-irrigation and other types of irrigation remove air from the root zone of plants during irrigation, causing a sharp drop in air permeability and oxygen levels in the moist soil area surrounding the roots. This significantly limits the roots' access to oxygen, hindering crop growth and affecting crop yields.

[0003] Due to the low solubility of oxygen in water, oxygen in agricultural irrigation water is primarily present in the form of bubbles. Common methods for aeration in agricultural irrigation currently include Venturi jet aeration, air compressor aeration, and chemical aeration. These mechanical aeration methods produce large bubbles, short retention times, and low oxygen dissolution efficiency, making them ineffective in achieving oxygenation in long-distance micro-irrigation pipes. Chemical aeration is currently primarily used in scientific research, and whether long-term use will adversely affect soil remains under debate, making it difficult to promote in agricultural production applications.

[0004] In recent years, advanced micro-nano bubble technology has been primarily applied in wastewater treatment, petrochemicals, nuclear power molten salt, and other fields. Due to their small size and large specific surface area, micro-nano bubbles exhibit slow buoyancy, long duration, self-pressurized dissolution, and high gas dissolution efficiency, making them an excellent air carrier for long-distance oxygenated irrigation. Based on the principle of micro-nano bubble generation, micro-nano bubble generation devices can be categorized into electrolytic, pressurized dissolved air release, dispersed air, ultrasonic cavitation, and photocatalytic types. The prior art discloses a micro-nano bubble generator that uses a cutting net to cut bubbles in a liquid to form micro-nano bubbles. However, the manufacturing process of the cutting net is demanding, and the micropores of the cutting net are easily clogged. The prior art discloses a generator for preparing micro-nano bubble water that first uses ionization to remove positive ions in the air, then forcibly pressurizes and dissolves the negatively charged air in water, and finally decompresses the air through an exhaust valve to precipitate a large number of micro-nano bubbles. However, the device has numerous supporting facilities, occupies a large space, and is costly. The prior art discloses a variable-pitch micro-nano bubble generating device that stabilizes the flow state of the micro-nano bubble liquid through continuously spiral variable-pitch rectifying blades. However, the cavity structure with the rectifying blades built in is relatively complex and difficult to process.

[0005] Existing micro-nano bubble generators vary significantly in their bubble-forming performance and applicability. However, they are generally large, complex, and costly, hindering their widespread application in micro-irrigation systems, let alone agricultural production. Therefore, the development of a micro-nano bubble generator that is compact, easy to install and disassemble, simple in structure, and low in cost is crucial to addressing this gap in agricultural oxygenation irrigation. Summary of the Invention

[0006] In response to the shortcomings of the existing technology, the present invention provides a slit-type micro-nano bubble generator, which has the advantages of simple device structure, low cost, small bubble particle size, long duration and fast oxygen dissolution efficiency, and is very suitable for promotion to agricultural oxygen enrichment irrigation production practice.

[0007] The present invention achieves the above technical objectives through the following technical means.

[0008] A slit-type micro-nano bubble generator comprises a main body and a pressure plate. The main body is a polyhedron, at least one face of which is mounted with a gas-liquid mixing device, and the end faces of the remaining polyhedrons serve as water outlet surfaces. A main flow channel and a secondary flow channel are provided within the main body. The main flow channel is connected to the inlet of the gas-liquid mixing device, and the main flow channel is connected to the water outlet surface via a plurality of secondary flow channels. A turbulent flow chamber is formed between the water outlet surface of each main body and the pressure plate via a flow channel assembly for producing and outputting nanobubbles.

[0009] Furthermore, the flow channel assembly is composed of a plurality of gaskets or irregular gaskets, and the plurality of gaskets are installed between the water outlet surface of the main body and the pressure plate.

[0010] Furthermore, the flow channel assembly is composed of circular gaskets uniformly distributed between the water outlet surface of the main body and the pressure plate. The inscribed circles between the uniformly distributed circular gaskets form a turbulent cavity, and the cavity between adjacent circular gaskets forms a micro-nano bubble outlet.

[0011] Furthermore, the flow channel component is a flow channel gasket, and a groove is provided on the surface of the flow channel gasket, which is connected to the flow channel to form a turbulent cavity; and at least one gradually expanding opening is provided on the groove to form a micro-nano bubble outlet.

[0012] Furthermore, the thickness of the turbulent cavity is 0.3-0.8 mm.

[0013] Furthermore, the gas-liquid mixing device is a Venturi joint, and the interior of the shell of the Venturi joint is provided with a liquid inlet, a tapering section, a narrow section, a gradually expanding section and a gas-liquid outlet in sequence according to the liquid flow direction. An air inlet is provided on the side wall of the shell, and the air inlet is connected to the narrow section for gas-liquid mixing; the gas-liquid outlet is connected to the main channel.

[0014] Furthermore, the diameter of the main flow channel is 10 to 18 mm, and the diameter of the secondary flow channel is 3 to 5 mm.

[0015] Furthermore, a turbulent cavity is formed between the water outlet surface of any main body and the water outlet surface of another slit-type micro-nano bubble generator through the flow channel component.

[0016] The beneficial effects of the present invention are:

[0017] 1. The slit-type micro-nano bubble generator described in the present invention adopts a regular hexahedron structure, which simplifies the difficulty of device processing and manufacturing. The turbulent chamber is composed of the gap between the pressure plate and the water outlet surface. The turbulent chamber does not require additional processing, which reduces manufacturing costs.

[0018] 2. The slit-type micro-nano bubble generator described in the present invention adopts a vertical liquid inlet and lateral liquid outlet mode, and the device structure is exquisite and compact.

[0019] 3. The upper part of the slit-type micro-nano bubble generator described in the present invention can be replaced with different joints, and the size of the turbulent chamber can be changed by the gasket on the screw. It can be applied to different working conditions, and more types of gaskets can be replaced or supplemented according to the actual working conditions.

[0020] 4. The slit-type micro-nano bubble generator described in the present invention can generate bubbles on all five sides except the top, which can greatly improve the bubble generation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. The drawings described below are some embodiments of the present invention. For ordinary technicians in this field, it is obvious that other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 This is a three-dimensional diagram of the slit-type micro-nano bubble generator described in the present invention.

[0023] Figure 2 This is a top view of the slit-type micro-nano bubble generator described in the present invention.

[0024] Figure 3 for Figure 2 AA cross-sectional view.

[0025] Figure 4 A three-dimensional diagram of the Venturi joint.

[0026] Figure 5 A top view of the Venturi joint.

[0027] Figure 6 for Figure 5 Cross-sectional view of BB.

[0028] Figure 7 This is a three-dimensional diagram of a flow channel gasket.

[0029] Figure 8 This is a curve diagram of the change of dissolved oxygen in water over time when the slit-type micro-nano bubble generator of the present invention is in operation and after being left to stand.

[0030] Figure 9 Generates a bubble effect diagram for the job, where Figure 9 a is the bubble effect diagram produced by five sides working simultaneously. Figure 9 b is the bubble effect diagram produced by single-sided work.

[0031] In the picture:

[0032] 1-main flow channel; 2-sub-flow channel; 3-pressure plate; 4-gas-liquid mixing outlet; 5-turbulent chamber; 6-screw interface; 7-narrow section; 8-converging section; 9-air inlet; 10-expanding section; 11-gasket. DETAILED DESCRIPTION

[0033] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0034] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "axial", "radial", "vertical", "horizontal", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0035] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0036] like Figure 1 and Figure 2 As shown, the slit-type micro-nano bubble generator of the present invention includes a main body and a pressure plate 3. The main body is a polyhedron, and a gas-liquid mixing device is installed on at least one surface of the polyhedron, and the end surface of the remaining polyhedron is a water outlet surface; a main flow channel 1 and a secondary flow channel 2 are provided in the main body; the main flow channel 1 is connected to the inlet of the gas-liquid mixing device, and the main flow channel 1 is connected to the water outlet surface through a plurality of secondary flow channels 2; a turbulent cavity 5 is formed between the water outlet surface of each main body and the pressure plate 3 through a flow channel component for producing and outputting nanobubbles.

[0037] The slit-type micro-nano bubble generator described in this invention operates as follows: a gas-liquid mixture enters through the gas-liquid mixing inlet, flows through the main flow channel 1, flows into the narrow secondary flow channel 2, and then exits the gas-liquid mixing outlet 4, where the pressure rapidly increases. The mixed liquid is broken into tiny bubbles under high speed and high pressure in the gap formed between the pressure plate 3 and the water outlet. The tiny bubbles trapped in the turbulent flow chamber flow out through the gaps on both sides, ultimately producing micro-nano bubble water.

[0038] Example 1

[0039] like Figure 1 , Figure 2 and Figure 3 As shown, the slit-type micro-nano bubble generator of the present invention comprises a main body and five pressure plates 3. The main body is a regular hexahedron, with a gas-liquid mixing inlet at its top, threaded with a G1 / 2 thread size. The remaining five end faces of the main body serve as water outlets. The main body is provided with a main flow channel 1 and secondary flow channels 2. The main flow channel 1 is connected to the gas-liquid mixing inlet, which in turn is connected to the water outlet via several secondary flow channels 2. The gas-liquid mixing inlet directly introduces the gas-liquid mixing medium.

[0040] The structure's main flow channel 1 communicates with secondary flow channels 2, which flow to five outlet surfaces. A pressure plate 3, at screw connections 6, uses screws to maintain a fixed gap between the outlet surfaces. Each screw has a gasket 11 to maintain the thickness of the gap. The gap between the outlet surfaces and the pressure plate forms a turbulent chamber 5, which is used to generate and discharge micro-nano bubbles.

[0041] The flow channel assembly is composed of circular gaskets uniformly distributed between the water outlet surface of the main body and the pressure plate 3. The inscribed circles between the uniformly distributed circular gaskets form a turbulent cavity 5, and the cavity between adjacent circular gaskets forms the micro-nano bubble outlet. The thickness of the gasket 11 determines the form and thickness of the turbulent cavity 5. The thickness of the turbulent cavity 5 is one of the key parameters for the device to generate micro-nano bubbles. If the thickness of the turbulent cavity is too large, the turbulence intensity of the mixed liquid in the cavity will be greatly reduced, the degree of bubble turbulence fragmentation will be insufficient, and the bubble particle size will be large. Experimental results have determined that the thickness of the turbulent cavity ranges from 0.3 to 0.8 mm.

[0042] In Example 1, the side length of the regular hexahedron structure is 45 mm, the diameter of the main channel 1 is 12 mm, the diameter of the secondary channel 2 is 3 mm, and the length of the secondary channel diameter is 16.5 mm. The pressure plate used in this implementation example is a 45*45*10 square pressure plate. The screws used to secure the gap between the pressure plate and the water outlet are M6*8.

[0043] After testing, the working pressure is 300KPa and the liquid flow rate is 1.2m 3 / h, when the gas content is 1% of the liquid flow rate, the dissolved oxygen and foaming effects after the operation of the device are relatively ideal; the micro-nano bubble generating device is placed in water with a temperature of 13.4°C, a volume of 40L, and an initial dissolved oxygen of 10.40mg / L. After running for 2 minutes under the above working conditions and then standing, a curve of the change of dissolved oxygen over time is obtained, as shown in Figure 8 As shown in the curve, it can be seen that within 2 minutes of the operation of the device of the present invention, the dissolved oxygen concentration in the water increased rapidly and reached a peak of 11.25 mg / L within 10 seconds after the device stopped operating. Within 1 minute after the device stopped operating, the dissolved oxygen concentration in the water first dropped rapidly to 11.06 mg / L, and then showed a fluctuating downward trend. After standing for 8 minutes, the dissolved oxygen concentration in the water was still higher than 10.9 mg / L. Figure 9 As shown in the figure, the bubble particle size effect comparison diagram of the device of the present invention and the single-sided bubble generating device based on the same principle is shown under the same working condition of 300KPa pressure, after running for 1 minute and then standing for 30 seconds. It can be seen intuitively from the image that the device of the present invention works simultaneously on five sides and can generate a large number of uniform tiny bubbles in a short time.

[0044] Example 2

[0045] On the basis of Example 1, the flow channel component is a flow channel gasket, such as Figure 7As shown, the surface of the channel-type gasket is provided with a groove that connects to the secondary flow channel 2 to form a turbulent chamber 5. The groove has at least one gradually expanding opening that forms a mixed liquid outlet. The channel-type gasket has a thickness of 1.5 to 2.0 mm. The gas-liquid mixture flows into the turbulent chamber 5, where it is broken down by turbulent flow to form tiny bubbles that flow out of the device along the mixed liquid outlet. The groove of the channel-type gasket can be a single groove or a combination of multiple grooves of different shapes.

[0046] Example 3

[0047] On the basis of Example 1, a venturi joint is installed on the gas-liquid mixing inlet, such as Figure 4 , Figure 5 and Figure 6 As shown, the interior of the Venturi connector shell is equipped with a liquid inlet, a tapered section 8, a narrow section 7, a gradually expanding section 10, and a gas-liquid outlet, sequentially arranged according to the liquid flow direction. The shell sidewall is provided with an air inlet 9, which communicates with the narrow section 7 for gas-liquid mixing; the gas-liquid outlet is connected to the main channel 1. Liquid enters through the water inlet, and gas enters through the air inlet. The liquid flows through the tapered section 8 and the narrow section 7. The high-speed flow of liquid generates negative pressure, driving the gas out of the air inlet 9 to form a mixed liquid. The mixed liquid then flows from the gradually expanding section 10 to the regular hexahedron structure, achieving the same effect. The Venturi connector body has a diameter d3 of 12 mm and a length L4 of 30 to 50 mm. The inner G1 / 2 at the water inlet, the inner diameter of the water inlet flow channel is 12mm. The Venturi structure has a diameter d4 of the narrow section 7 of 5mm, a length L3 of 10mm, a length L6 of the tapered section 8 of 5mm, a length L5 of the gradually expanding section 10 of 8mm, an air outlet of 6*1.2mm, a diameter of the inlet flow channel of 3mm, an inner G1 / 2 at the air inlet, and an outer G1 / 2 at the gas-liquid mixing outlet, which is connected to the regular hexahedron structure below.

[0048] In addition, a turbulent cavity 5 is formed between the water outlet surface of any main body and the water outlet surface of another slit-type micro-nano bubble generator through a flow channel component, so that a plurality of slit-type micro-nano bubble generators can be connected.

[0049] It should be understood that although this specification is described according to various embodiments, not every embodiment contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0050] The series of detailed descriptions listed above are only specific descriptions of feasible embodiments of the present invention. They are not intended to limit the scope of protection of the present invention. Any equivalent embodiments or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A slit-type micro-nano bubble generator, characterized in that: The invention comprises a main body and a pressure plate (3), wherein the main body is a polyhedron, at least one surface of the main body is provided with a gas-liquid mixing device, and the end surface of the remaining polyhedron is a water outlet surface; a main flow channel (1) and a secondary flow channel (2) are provided in the main body; the main flow channel (1) is connected to the outlet of the gas-liquid mixing device, and the main flow channel (1) is connected to the water outlet surface through a plurality of secondary flow channels (2); a turbulent flow chamber (5) is formed between the water outlet surface of each main body and the pressure plate (3) through a flow channel component, and is used for producing and outputting micro-nano bubbles; the gas-liquid mixing device is a Venturi joint, The shell of the Venturi joint is provided with a liquid inlet, a tapered section (8), a narrow section (7), a gradually expanding section (10) and a gas-liquid outlet in sequence according to the liquid flow direction. The side wall of the shell is provided with an air inlet (9), which is connected to the narrow section (7) for gas-liquid mixing; the gas-liquid outlet is connected to the main channel (1); the flow channel assembly is composed of a flow channel gasket or a uniformly distributed circular gasket, and the flow channel gasket or the circular gasket is installed between the water outlet surface of the main body and the pressure plate (3); the thickness of the turbulent chamber (5) is 0.3~0.8 mm.

2. The slit-type micro-nano bubble generator according to claim 1, characterized in that: The flow channel assembly is composed of circular gaskets uniformly distributed between the water outlet surface of the main body and the pressure plate (3); the inscribed circles between the uniformly distributed circular gaskets form a turbulent cavity (5); and the cavities between adjacent circular gaskets form micro-nano bubble outlets.

3. The slit-type micro-nano bubble generator according to claim 1, characterized in that: The flow channel component is a flow channel gasket, the surface of which is provided with a groove, the groove being in communication with the secondary flow channel (2) and being used to form a turbulent cavity (5); the groove is provided with at least one gradually expanding opening for forming a micro-nano bubble outlet.

4. The slit-type micro-nano bubble generator according to any one of claims 1 to 3, characterized in that: The main flow channel (1) has a diameter of 10 to 18 mm, and the secondary flow channel (2) has a diameter of 3 to 5 mm.

5. The slit-type micro-nano bubble generator according to any one of claims 1 to 3, characterized in that: A turbulent flow cavity (5) is formed between the water outlet surface of any one main body and the water outlet surface of another slit-type micro-nano bubble generator through a flow channel component.

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