A microporous bubbling aeration two-stage oscillation modulation efficiency enhancement system and its application method

Abstract

The present invention discloses a microporous bubbling aeration two-stage oscillation modulation efficiency enhancement system and its application method. The modulation efficiency enhancement system includes a two-stage oscillation device, a gas supply unit connected upstream of the two-stage oscillation device, and a microporous coil pipe and an aeration tank connected downstream of the two-stage oscillation device. The two-stage oscillation device includes a non-feedback oscillation cavity connected to a branch section, a sound wave oscillation cavity connected in sequence to an air inlet section, and a connecting cavity section connected in parallel to the non-feedback oscillation cavity and the sound wave oscillation cavity. The present invention injects a controlled pulsating oscillating air flow into the microporous aeration system through the two-stage oscillation device, introducing periodic inertial force disturbances in the bubble generation stage; the pulsating pressure field breaks the gas-liquid interface force balance under the traditional steady-state air flow, significantly reducing the critical size for bubble detachment: the high-frequency pressure oscillation accelerates the oscillation of the orifice air film, promotes necking and fracture, and reduces the detached volume of the bubble; at the same time, the transient shear force generated by the pulsating air flow inhibits the interaction of the wakes of adjacent bubbles, reducing the coalescence probability.

Description

Technical Field

[0001] The present invention relates to the technical field of aeration, and particularly relates to a microporous bubbling aeration two-stage oscillation modulation efficiency enhancement system and an application method thereof. Background Art

[0002] Microporous aeration has been widely used in the activated sludge process of sewage treatment. In the field of sewage treatment, an aeration system provides dissolved oxygen for microbial metabolism. However, traditional microporous aeration technology is restricted by factors such as microporous manufacturing precision, material deformation, and surface wettability. It is difficult to continuously and stably generate small-sized bubbles as theoretically expected. The median diameter of the actually generated bubbles generally exceeds the design value (usually reaching 2 - 5 mm). At the same time, the bubble formation mechanism dominated by the gas-liquid interfacial tension under steady-state gas flow conditions is prone to cause the coalescence effect of adjacent bubbles. Especially in a higher gas velocity or complex medium environment, the proportion of the bubble group combining to form millimeter-sized large bubbles increases significantly. Therefore, seeking a technical method that adapts to the microporous bubbling aeration mode, can reduce the bubble size, and strengthen the gas-liquid interfacial mass transfer reaction has thus become a major practical need in the field. Summary of the Invention

[0003] The present invention provides a microporous bubbling aeration two-stage oscillation modulation efficiency enhancement system and an application method thereof to solve technical problems such as breaking the traditional steady mass transfer interface, avoiding the low single-stage oscillation frequency, enhancing and precisely controlling the generation of microbubbles, and modular and convenient setting.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] A microporous bubbling aeration two-stage oscillation modulation efficiency enhancement system includes a two-stage oscillation device, a gas supply unit connected upstream of the two-stage oscillation device, and a microporous coil pipe and an aeration tank connected downstream of the two-stage oscillation device;

[0006] The two-stage oscillation device includes an air inlet section, a branch section connected to one side of the air inlet section, a non-feedback oscillation chamber connected to the branch section, a sound wave oscillation chamber connected in series with the air inlet section, a connecting chamber section connecting the non-feedback oscillation chamber and the sound wave oscillation chamber in parallel, and an air outlet section connected in series to the outlet of the sound wave oscillation chamber; the air outlet section is connected to the microporous coil pipe downstream;

[0007] The non-feedback oscillation chamber includes a non-feedback chamber air inlet section connected in series with the branch section, a non-feedback chamber contraction pipe section connected to the non-feedback chamber air inlet section, a non-feedback chamber double-port gas supply section connected in series with the non-feedback chamber contraction pipe section, a counter-jet oscillation main chamber connected to the non-feedback chamber double-port gas supply section, and a non-feedback chamber outlet shunt section connected after the counter-jet oscillation main chamber; the non-feedback chamber outlet shunt section is connected in parallel with the sound wave oscillation chamber through the connecting chamber section.

[0008] Further, the air supply unit includes an air supply source connected by a pipeline, a valve installed on the downstream pipeline of the air supply source, a pressure regulating filter installed downstream of the valve, and a flow meter installed downstream of the pressure regulating filter;

[0009] A double-stage oscillation device is correspondingly installed on the downstream pipeline of the flow meter.

[0010] Further, the intake section is the main pipeline, and the main pipeline is connected in series to the downstream pipeline of the flow meter; a branch section is provided on one side of the main pipeline; the width or diameter of the branch section is not greater than the width or diameter of the main pipeline; the flow rate of the branch section accounts for 3% - 8% of the flow rate of the intake section.

[0011] Further, the intake section of the non-feedback cavity is tapered, and the width or diameter of the outlet of the intake section of the non-feedback cavity corresponds to the width or diameter of the contraction section of the non-feedback cavity; the included angle between the contraction angle of the intake section of the non-feedback cavity and the horizontal line is 12 - 17 degrees, and the inlet width is selected according to the standard thread diameter; the length of the intake section of the non-feedback cavity is greater than or equal to 2 times the length of the contraction section of the non-feedback cavity; the contraction section of the non-feedback cavity is a straight pipe, and its length is 3 - 4 times the width or diameter, and the width or diameter is 1 / 3 - 1 / 2 of the width or diameter at the inlet of the intake section of the non-feedback cavity.

[0012] Further, the double-port air supply section of the non-feedback cavity is divided into two by connecting to the contraction section of the non-feedback cavity and symmetrically enters the counter - impact oscillation main cavity; the double-port air supply section of the non-feedback cavity is divided into a straight section and an arc section on one side. The straight section is tapered, and the arc section has a constant width or diameter. The width or diameter of the arc section corresponds to the width or diameter of the outlet of the straight section;

[0013] The distance from the vertex of the flow - dividing wedge in the double-port air supply section of the non-feedback cavity to the end of the contraction section of the non-feedback cavity is 4 - 8 times the width of the double-port air supply section of the non-feedback cavity.

[0014] Further, the counter - impact oscillation main cavity is in the shape of an elliptical box, and the included angle between the double-port air supply section of the non-feedback cavity connecting to the counter - impact oscillation main cavity and the horizontal line is 25 - 35 degrees;

[0015] O is the center of the oscillation cavity, H1 is the straight-line distance from the center of the oscillation cavity to the upstream cavity wall, H2 is the straight-line distance from the center of the oscillation cavity to the outlet of the downstream cavity, L0 is the distance between the inlets of the two double-port air supply sections of the non-feedback cavity, L1 is the distance from the inlet of the double-port air supply section of the non-feedback cavity to the center of the cavity, L2 is the distance of the outlet straight section, W1 is the width or diameter at the outlet of the arc section of the double-port air supply section of the non-feedback cavity; W2 is the outlet width or diameter;

[0016] The parameters are set as follows: H1 is 5 - 6 times W1, H2 is 4.0 - 4.5 times W1, L0 is 9 - 11 times W1, L1 is 6 - 8 times W1, L2 is 2.5 - 3.5 times W1, and W2 is 1.8 - 2.5 times W1;

[0017] The outlet shunt section of the non-feedback cavity is bifurcated into two parts at the connection with the opposed oscillating main cavity and is arranged in a V shape; the angle O1 between the outer side of each outlet edge and the horizontal line is 18 to 25 degrees, and the angle O2 between the inner side and the horizontal line is 12 to 19 degrees; and the outlet on each side is arranged in a gradually expanding shape;

[0018] The distance H3 from the bifurcation point at the connection to the outlet of the opposed oscillating main cavity is 4 to 9 times of W2, and the bifurcation point is smoothly arranged.

[0019] Furthermore, the sonic oscillation cavity includes a sonic cavity inlet section connected to the inlet section, a sonic oscillation feedback cavity connected downstream of the sonic cavity inlet section, and a sonic cavity outlet section connected downstream of the sonic oscillation feedback cavity in sequence;

[0020] The sonic cavity inlet section includes a gradually tapered contraction tube and a throat tube, and the contraction angle β of the gradually tapered contraction tube is 10 to 15 degrees; the width or diameter W3 of the throat tube is 9 to 12 times of W1, the length of the throat tube is L3, and the length L3 is 3 to 4 times of W3;

[0021] The sonic oscillation feedback cavity is symmetrically shaped like a water droplet, the included angle γ between the sonic oscillation feedback cavities on both sides of the sonic cavity inlet section is 10 to 15 degrees, and the width near the throat of the sonic oscillation feedback cavity is 0.5 to 0.9 times of W3.

[0022] Furthermore, the sonic cavity outlet section is arranged in the middle of the two sonic oscillation feedback cavities and is split into two outlet channels, the distance P between the two top points of the split is 1.5 to 3 times of W3, the distance H4 from the split tip to the middle outlet of the sonic oscillation feedback cavity is 4 to 11 times of the throat width W3, and the split radius is 0.1 to 2 times of W3.

[0023] The angle O1 between the outer side of each side of the sonic cavity outlet section and the horizontal line is 18 to 25 degrees, and the angle O2 between the inner side and the horizontal line is 12 to 19 degrees.

[0024] Furthermore, there are two connection sections. One connection section connects one outlet side of the non-feedback cavity outlet shunt section and one outlet side of the sonic cavity outlet section; the other connection section connects the other outlet side of the non-feedback cavity outlet shunt section and the other outlet side of the sonic cavity outlet section.

[0025] Furthermore, the application method of the microporous bubble aeration two-stage oscillation modulation and efficiency enhancement system is as follows:

[0026] Step 1: Supply gas through a gas supply source, and control the air flow velocity and flow rate through a valve and a pressure regulating filter; then the air flow enters the inlet section of the two-stage oscillation device through a pipeline;

[0027] Step 2: The air flow is shunted from the inlet section to the branch section, and the air flow enters the non-feedback cavity inlet section, passes through the non-feedback cavity contraction tube section and the non-feedback cavity dual-port gas supply section and enters the opposed oscillating main cavity;

[0028] Step 3: After the air flow enters the counter-oscillation main cavity, initially, the main jet does not deflect, the flow field remains uniformly distributed, and the air flows out uniformly from the two outlet shunt sections of the non-feedback cavities. Immediately afterwards, one of the two supply jets entering from both sides establishes a main connection with the outlet of the counter-oscillation main cavity and jets out in the forward direction, while the other supply jet forms a vortex region inside the circular cavity of the counter-oscillation main cavity.

[0029] Step 4: Due to the inherent turbulence and entrainment effect of the jet, and affected by the shunt splitter, the previous equilibrium state is disrupted, and a pressure difference appears on both sides of the shunt splitter. When the pressure difference reaches a certain order of magnitude, the jet starts to tilt and deflect towards the lower sidewall with lower pressure, and at the same time, a stable wall attachment phenomenon occurs, and it flows out along the outlet pipe on that side at a higher speed than the other sidewall.

[0030] Step 5: Subsequently, since the vortex region inside the circular cavity is large enough and collides with the jet at the action point, the main connection between the jet and the outlet of the circular cavity is broken, and a new vortex region gradually forms inside the circular cavity, prompting the other supply jet to establish a main connection with the outlet of the circular cavity and jet out in the negative direction. At this time, due to the inherent turbulence and entrainment effect of the jet itself, a pressure difference relationship opposite to the previous one appears on both sidewalls of the shunt splitter, causing the jet to deflect towards the upper sidewall and flow out along the outlet pipe on that side at a high speed, and one switching is completed. Finally, due to the action of a different internal vortex region from the previous stage, the initial supply jet re-establishes a main connection with the outlet of the circular cavity, and the jet also correspondingly switches and attaches to the lower sidewall. The oscillation occurs due to the interaction between the two jets inside the circular cavity, and the continuation of the oscillation stems from the periodic wall attachment switching behavior of the jet.

[0031] Step 6: After the air flow in the intake section enters the sound wave oscillation cavity, the boundary layer separation effect forms low-pressure vortex regions on both sides of the jet; the pressure value of the low-pressure vortex region on one side is higher, pushing the main jet to the other side and causing it to attach to the wall; the pressure reduction on the non-wall-attached side leads to a large amount of air being entrained on that side. At the same time, the pulsating jet from the outlet of the non-feedback oscillation cavity intermittently applies a fluctuating pressure through the feedback pipes on both sides of the main jet in the sound wave oscillation cavity. Coupled with the entrainment effect, the pressure on the wall-attached side rises rapidly. After exceeding the non-wall-attached side, it pushes the main jet back to form a new wall-attached side, thus completing half a cycle of switching; similarly, on the new wall-attached side, which was the non-wall-attached side before, the "entrainment - push - switch" process occurs to complete the entire cycle of switching; such a cyclic "wall attachment - entrainment - switch" periodic motion enables the incoming main jet to flow out quickly and alternately along the two outlets, forming a high-frequency pulsed oscillating flow.

[0032] Step 7: Based on the high-frequency pulsed oscillating flow formed in the acoustic oscillation chamber, after the gas flows out from the outlet section of the acoustic chamber, it is successively connected to the microporous coiled pipe and the aeration tank, thus completing the application of the microporous bubble aeration two-stage oscillation modulation efficiency enhancement system.

[0033] The beneficial effects of the present invention are as follows:

[0034] Based on the principle of unsteady gas-liquid interface dynamics, the present invention injects a controlled pulsating oscillating air flow into the microporous aeration system through a two-stage oscillation chamber, and introduces a periodic inertial force disturbance in the bubble generation stage. When the gas flows through the micropores, the pulsating pressure field breaks the gas-liquid interface force balance (the static balance of surface tension, buoyancy and viscous force) under the traditional steady air flow, so that the critical size for bubble detachment is significantly reduced: the high-frequency pressure oscillation accelerates the oscillation of the orifice gas film, promotes necking and fracture, and reduces the bubble detachment volume; at the same time, the transient shear force generated by the pulsating air flow inhibits the interaction between the wakes of adjacent bubbles and reduces the coalescence probability.

[0035] The present invention breaks through the limitations of the traditional static air flow mode and the low oscillation frequency of the single-stage oscillation chamber, reconstructs the bubble generation dynamics process through the two-stage oscillation chamber, realizes precise control of the bubble size, and does not require modification of the microporous structure or replacement of the aeration material. The self-cleaning effect is generated by the pulsating air flow, reducing the attachment rate of the biofilm / particulates on the microporous surface (the measured fouling cycle is extended by 2-3 times), and is especially suitable for the high-suspended solid wastewater scenario.

[0036] The present invention matches the bubble generation cycle through pulsed air supply, reduces the air volume demand by 15%-25% compared with continuous aeration, and combines with the improvement of mass transfer efficiency, and the comprehensive energy saving rate exceeds 40%. The modular two-stage oscillation device can be installed independently of the aerator, is compatible with various microporous aeration systems such as ceramics / rubbers / polymers, and the transformation and upgrading cost is only 10%-20% of the traditional technical solution; based on the real-time dissolved oxygen feedback, the pulsating parameters (frequency / amplitude) are dynamically adjusted to realize the adaptive optimization of the aeration process, breaking through the regulation hysteresis bottleneck of the traditional aeration system.

[0037] The unsteady two-stage oscillating cavity pulsating air flow modulation method proposed by the present invention constructs a periodic pressure oscillation field, forms a dynamic shear effect at the micro-hole gas-liquid interface, and effectively breaks through the physical constraint that the pore size determines the bubble size in traditional aeration. The main innovative features of this method are as follows: Firstly, the dynamic pressure pulsation of the air flow is used to break the continuity of the gas film and achieve active control of bubble breakage; Secondly, through the coordinated regulation of the modulation frequency and amplitude, a quantitative response mechanism between the bubble size and the energy input is established; Thirdly, while maintaining the low energy consumption advantage of traditional micro-hole aeration, the mass transfer efficiency per unit energy consumption is significantly improved. In industrial practice, this technology can be compatible with the upgrading and transformation of existing aeration devices, and has a significant efficiency-enhancing effect on complex working conditions such as high-concentration organic wastewater treatment and high-viscosity reaction systems, providing an innovative solution for breaking through the energy efficiency bottleneck of traditional aeration technology. The equipment of this patented technology can effectively strengthen the mass transfer and reaction at the gas-liquid two-phase interface, and is applied to fields such as chemical gas-liquid reactions, separation of volatile substances, and water body aeration and reoxygenation.

[0038] Other features and advantages of the present invention will be described in the following specification, and will be partially obvious from the specification, or understood by implementing the present invention; the main objectives and other advantages of the present invention can be achieved and obtained through the solutions specifically pointed out in the specification. Brief Description of the Drawings

[0039] Figure 1 is a three-dimensional schematic diagram of a two-stage oscillating modulation efficiency-enhancing system for micro-hole bubbling aeration and a two-stage oscillating device;

[0040] Figure 2 is a cross-sectional schematic diagram of the two-stage oscillating device;

[0041] Figure 3 is a schematic diagram of the structure of the branch section and the non-feedback oscillating cavity;

[0042] Figure 4 is a schematic diagram of the connection structure between the double-port air supply section of the non-feedback cavity and the counter-jet oscillating main cavity;

[0043] Figure 5 is a schematic diagram of the structure of the sound wave oscillating cavity;

[0044] Figure 6 is a schematic diagram of the simulation of the non-feedback jet oscillation process;

[0045] Figure 7 is a schematic diagram of the simulation of the sound wave jet oscillation process driven by non-feedback jet oscillation and wall attachment effect;

[0046] Figure 8 is a signal data diagram of the outlet pressure sensor of the two-stage oscillating device;

[0047] Figure 9 is a comparison diagram of the oxygenation rate of the porous aeration disc 1 when using / not using this system;

[0048] Figure 10 It is a comparison chart of the oxygenation rate of the porous aeration disk 2 when using / not using this system.

[0049] Reference numerals: 1 - air supply source, 2 - valve, 3 - pressure regulating filter, 4 - flowmeter, 5 - pipeline, 6 - double-stage oscillation device, 61 - intake section, 62 - branch section, 63 - non-feedback oscillation chamber, 631 - non-feedback chamber intake section, 632 - non-feedback chamber contraction pipe section, 633 - non-feedback chamber double-port air supply section, 634 - counter-jet oscillation main chamber, 635 - non-feedback chamber outlet shunt section, 64 - sound wave oscillation chamber, 641 - sound wave chamber intake section, 642 - sound wave oscillation feedback chamber, 643 - sound wave chamber outlet section, 65 - connecting chamber section, 66 - outlet section, 7 - microporous coil, 8 - aeration tank. Detailed implementation manners

[0050] As Figures 1 to 6 shown, a microporous bubbling aeration double-stage oscillation modulation and efficiency enhancement system includes a double-stage oscillation device 6, an air supply unit connected upstream of the double-stage oscillation device 6, and a microporous coil 7 and an aeration tank 8 connected downstream of the double-stage oscillation device 6.

[0051] In this embodiment, the air supply unit includes an air supply source 1 connected through a pipeline 5, a valve 2 installed on the pipeline 5 downstream of the air supply source 1, a pressure regulating filter 3 installed downstream of the valve 2, and a flowmeter 4 installed downstream of the pressure regulating filter 3; the double-stage oscillation device 6 is correspondingly installed on the pipeline 5 downstream of the flowmeter 4. The intake section 61 is the main pipeline, and the main pipeline is connected in series to the pipeline 5 downstream of the flowmeter 4; a branch section 62 is provided on one side of the main pipeline; the pipeline width or diameter of the branch section 62 is not greater than the width or diameter of the main pipeline; the flow rate of the branch section 62 accounts for 3% - 8% of the flow rate of the intake section 61.

[0052] Among them, the air supply source 1 is generally a blower such as a Roots blower, a rotary blower or other forms of pressure air sources, and the air supply pressure range can reach 1 bar to 10 bar. The gas-phase working medium can be air, oxygen, nitrogen, carbon dioxide, etc. The air supply system is ensured to be stable through the switch valve 2, filter, pressure stabilizing valve, and flowmeter 4, and the working flow rate is determined according to actual needs to ensure that both the working pressure and flow rate are between 1 / 3 and 2 / 3 of the range of the pressure gauge and the flowmeter 4, and the final aeration pressure is generally between 0.2 bar and 1 bar.

[0053] In this embodiment, the double-stage oscillation device 6 includes an intake section 61, a branch section 62 connected to one side of the intake section 61, a non-feedback oscillation chamber 63 connected to the branch section 62, a sound wave oscillation chamber 64 connected in series to the intake section 61, a connecting chamber section 65 connected in parallel to the non-feedback oscillation chamber 63 and the sound wave oscillation chamber 64, and an outlet section 66 connected in series to the outlet of the sound wave oscillation chamber 64; the outlet section 66 is connected to the downstream microporous coil 7.

[0054] Among them, the double-stage oscillation device 6 is placed on the pipeline 5 between the gas supply source 1 and the microporous coil 7. The main air flow flows into the sound wave oscillation chamber 64, the branch air flow flows to the non-feedback oscillation chamber 63, and the outlet of the non-feedback oscillation chamber 63 is connected to both sides of the sound wave oscillation chamber 64. Pulse air flows can be formed at the two outlets of the sound wave oscillation chamber 64. At the rear end of the air flow in the main pipeline 5, multiple groups of the above double-stage oscillation devices 6 can be connected in parallel to obtain multiple pulse air flow outlets. The double-stage oscillation device 6 can be processed from materials such as stainless steel, copper, or acrylic according to the corrosiveness of the gas-phase working medium, and the requirements comply with the corresponding pressure safety levels. The double-stage oscillation device 6 can be used in any form in fields such as gas-liquid chemical reactions, environmental protection sewage aeration treatment, and agricultural aeration irrigation, and is applicable to any scale in laboratories and engineering sites. However, it is required that the working pressure and flow rate of the microporous air-diffusing component are adapted to the gas supply source 1. The double-stage oscillation device 6 has no restrictions on the microporous tube plate used at the rear end, and silicone rubber aeration discs, perforated pipes, corundum aeration discs, and ceramic discs can all be used.

[0055] In this embodiment, the non-feedback oscillation chamber 63 includes a non-feedback chamber intake section 631 connected in series to the branch section 62, a non-feedback chamber contraction pipe section 632 connected to the non-feedback chamber intake section 631, a non-feedback chamber double-port gas supply section 633 connected in series to the non-feedback chamber contraction pipe section 632, a counter-jet oscillation main chamber 634 connected to the non-feedback chamber double-port gas supply section 633, and a non-feedback chamber outlet shunt section 635 connected after the counter-jet oscillation main chamber 634; the non-feedback chamber outlet shunt section 635 is connected in parallel to the sound wave oscillation chamber 64 through the connecting chamber section 65.

[0056] In this embodiment, the non-feedback chamber intake section 631 is tapered, and the width or diameter of the outlet of the non-feedback chamber intake section 631 corresponds to the width or diameter of the non-feedback chamber contraction pipe section 632; the contraction angle of the non-feedback chamber intake section 631 with the horizontal line is between 12 and 17 degrees, and the inlet width is selected according to the standard thread diameter; the length of the non-feedback chamber intake section 631 is greater than or equal to 2 times the length of the non-feedback chamber contraction pipe section 632; the non-feedback chamber contraction pipe section 632 is a straight pipe, and its length is 3 to 4 times the width or diameter, and the width or diameter is 1 / 3 to 1 / 2 of the width or diameter at the inlet of the non-feedback chamber intake section 631.

[0057] In this embodiment, the double-port air supply section 633 without a feedback cavity is divided into two parts by connecting the contraction pipe section 632 without a feedback cavity in series, and symmetrically enters the counter-oscillation main cavity 634; the double-port air supply section 633 without a feedback cavity is divided into a straight section and an arc section on one side. The straight section is tapered, and the arc section is set with a constant width or diameter. The width or diameter of the arc section corresponds to the width or diameter of the outlet of the straight section; the distance from the vertex of the flow splitting wedge in the double-port air supply section 633 without a feedback cavity to the end of the contraction pipe section 632 without a feedback cavity is 4-8 times the width of the double-port air supply section 633 without a feedback cavity.

[0058] As Figure 4 shown, the counter-oscillation main cavity 634 is in the shape of an elliptical box. The angle between the double-port air supply section 633 without a feedback cavity connecting the counter-oscillation main cavity 634 and the horizontal line is the gas incident angle α, and the value of α is 25-35 degrees; O is the center of the oscillation cavity, H1 is the straight-line distance between the center of the oscillation cavity and the upstream cavity wall, H2 is the straight-line distance between the center of the oscillation cavity and the outlet of the downstream cavity, L0 is the distance between the inlets of the two double-port air supply sections 633 without a feedback cavity, L1 is the distance from the inlet of the double-port air supply section 633 without a feedback cavity to the center of the cavity, L2 is the distance of the outlet straight section, W1 is the width or diameter at the outlet of the arc section of the double-port air supply section 633 without a feedback cavity; W2 is the outlet width or diameter; the parameters are set as follows: H1 is 5-6 times W1, H2 is 4.0-4.5 times W1, L0 is 9-11 times W1, L1 is 6-8 times W1, L2 is 2.5-3.5 times W1, W2 is 1.8-2.5 times W1; the outlet flow splitting section 635 without a feedback cavity is divided into two parts at the connection of the counter-oscillation main cavity 634 and is set in a V shape; the angle O1 between the outer side of each outlet edge and the horizontal line is 18-25 degrees, and the angle O2 between the inner side and the horizontal line is 12-19 degrees; and the outlet on each side is set in a gradually expanding shape; the distance H3 from the bifurcation point at the connection to the outlet of the counter-oscillation main cavity 634 is 4-9 times W2, and the bifurcation point is smoothly set.

[0059] As Figure 5 shown, the sound wave oscillation cavity 64 includes a sound wave cavity inlet section 641 connected to the intake section 61, a sound wave oscillation feedback cavity 642 connected downstream of the sound wave cavity inlet section 641, and a sound wave cavity outlet section 643 connected in series downstream of the sound wave oscillation feedback cavity 642; the sound wave cavity inlet section 641 includes a gradually changing contraction pipe and a throat pipe. The contraction angle β of the gradually changing contraction pipe is 10-15 degrees; the width or diameter of the throat pipe is W3, which is 9-12 times W1, and the length of the throat pipe is L3, and the length L3 is 3-4 times W3; the sound wave oscillation feedback cavity 642 is symmetrically in the shape of a water droplet, and the angle γ between the sound wave oscillation feedback cavities 642 on both sides of the sound wave cavity inlet section 641 is 10-15 degrees, and the width near the throat of the sound wave oscillation feedback cavity 642 is 0.5-0.9 times W3.

[0060] In this embodiment, the sonic cavity outlet section 643 is arranged in the middle of the two sonic oscillation feedback cavities 642 and the flow split is divided into two outlet flow channels, the distance P between the two tops of the split is 1.5-3 times of W3, the distance H4 between the tip of the split and the middle outlet of the sonic oscillation feedback cavity 642 is 4-11 times the throat width W3, and the split radius is 0.1-2 times of W3;

[0061] The angle between the outer side of each side of the sonic cavity outlet section 643 and the horizontal line is 18 to 25 degrees, and the angle between the inner side and the horizontal line is 12 to 19 degrees.

[0062] In this embodiment, two connecting cavity sections 65 are provided, one connecting cavity section 65 connects one outlet side of the no-feedback cavity outlet diversion section 635 and one outlet side of the sonic cavity outlet section 643; the other connecting cavity section 65 connects the other outlet side of the no-feedback cavity outlet diversion section 635 and the other outlet side of the sonic cavity outlet section 643.

[0063] Combination Figures 1 to 10 , further explain the application method of the microporous bubbling aeration two-stage oscillation modulation efficiency enhancement system, the specific steps are as follows:

[0064] Step 1: supply air through the air supply source 1, and control the air flow rate and flow rate through the valve 2 and the pressure regulating filter 3; then the air flow enters the air intake section 61 of the two-stage oscillation device 6 through the pipeline 5.

[0065] Step 2: The airflow is diverted from the air intake section 61 to the branch section 62, and the airflow enters the air intake section 631 of the non-feedback chamber, passes through the contraction tube section 632 of the non-feedback chamber and the double-port air supply section 633 of the non-feedback chamber, and enters the counter-oscillation main chamber 634.

[0066] Step 3: After the airflow enters the counter-oscillation main cavity 634, the initial main jet does not deviate, the flow field remains evenly distributed and flows out evenly from the two non-feedback cavity outlet diversion sections 635, as shown in FIG. Figure 6 As shown in a; then one of the two supply jets coming in from the inlets on both sides establishes a main connection with the outlet of the counter-oscillation main cavity 634 and is ejected in a forward direction, and the other supply jet forms a vortex zone inside the circular cavity of the counter-oscillation main cavity 634.

[0067] Step 4: Based on the turbulence and entrainment of the jet flow itself, and the influence of the splitter, the previous equilibrium state is affected, and a pressure difference appears on both sides of the splitter. When the pressure difference reaches a certain order of magnitude, the jet flow begins to tilt and deflect toward the lower wall surface with lower pressure, and a stable wall attachment phenomenon occurs, and the jet flows out along the outlet pipe on this side at a speed higher than that on the other side wall, such as Figure 6 As shown in b; Figure 6 Middle c shows that a low-pressure area can be observed on the wall side.

[0068] Step Five: As shown in d of Figure 6 , subsequently, since the eddy current region inside the circular cavity is large enough and collides with the injection jet at the action point, the main connection between the injection jet and the circular cavity outlet is broken, and a new eddy current region gradually forms inside the circular cavity, prompting another supply jet to establish a main connection with the circular cavity outlet and jet out negatively. At this time, due to the inherent turbulence and entrainment effect of the injection jet itself, a pressure difference relationship opposite to the previous one appears on both side walls of the shunt split, causing the jet to deflect towards the upper side wall and flow out at high speed along the outlet pipe on this side wall surface. The first switching is completed, as shown in e of Figure 6 . Finally, due to the action of the internal eddy current region different from the previous stage, the initial supply jet re - establishes a main connection with the circular cavity outlet again, and the injection jet also correspondingly switches and adheres to the lower side wall. The occurrence of oscillation stems from the interaction between the two jets in the circular cavity, and the continuation of oscillation stems from the periodic wall - attachment switching behavior of the injection jet, as shown in f of Figure 6 .

[0069] Step Six: As shown in Figure 7 , after the air flow in the intake section 61 enters the acoustic oscillation cavity 64, the boundary - layer separation effect forms low - pressure eddy current regions on both sides of the jet; the pressure value of the low - pressure eddy current region on one side is higher, pushing the main jet to the other side and making it adhere to the wall; based on Bernoulli's principle, the pressure on the non - wall - adhering side decreases, resulting in a large amount of air being entrained on this side. At the same time, the pulsating jet from the outlet of the non - feedback oscillation cavity 63 intermittently applies a fluctuating pressure through the feedback pipes on both sides of the main jet in the acoustic oscillation cavity 64. Coupled with the entrainment effect, the pressure on the wall - adhering side rises rapidly. After exceeding the non - wall - adhering side, it pushes the main jet over to form a new wall - adhering side. Thus, a half - cycle of switching is formed; similarly, on the new wall - adhering side, that is, the previous non - wall - adhering side, "entrainment - pushing - switching" occurs to complete the entire cycle of switching; such a cyclic "wall - attachment - entrainment - switching" periodic motion enables the incoming main jet to flow out quickly and alternately along the two outlets, forming a high - frequency pulsed oscillating flow.

[0070] Step Seven: Based on the high - frequency pulsed oscillating flow formed in the acoustic oscillation cavity, the gas flows out from the outlet section 643 of the acoustic cavity and is successively connected to the microporous coiled pipe 7 and the aeration tank 8, thus completing the application of the microporous bubbling aeration two - stage oscillation modulation and efficiency - increasing system.

[0071] In this embodiment, pressure data of the gas pipeline 5 downstream of the two - stage oscillation device 6 is collected and analyzed. The pressure sensor is a current - type sensor of a certain brand. Connecting the data collector can achieve pressure data collection at a maximum of 1000 Hz. The Figure 8 following is the signal data diagram of the pressure sensor of the air flow pipeline downstream of the two - stage oscillation modulation element. It can be clearly seen that the outlet pressure of the element shows a fluctuating state, and the pulsation frequency is about 54.88 Hz.

[0072] A microporous bubbling aeration experiment was carried out to verify whether the airflow modulated by the above-mentioned double-stage oscillation device 6 could bring about an increase in aeration efficiency; according to Figure 1 A microporous aeration simulation system was built. The air source was a certain brand of air compressor. The working pressure of the aeration system was 0.2 MPa, the flow rate was 30 L / min, and the porous aeration disc was a type 2 DN215 commercial aeration disc. The aeration tank 8 was a round barrel with a diameter of 0.6 m and a water depth of 0.8 m (the barrel height was 1.0 m). The aeration performance test was carried out according to the CJ / T 475-2015 standard. Sodium sulfite and cobalt chloride were used to remove the dissolved oxygen in the water to be tested in the initial state, so that it was reduced to less than 2.0 mg / L, and then the comparative oxygenation experiment with and without using this technical equipment was started. The mixing and mass transfer effect was measured by the rising speed of the dissolved oxygen concentration in the water, and the improvement effect of the self-excited airflow modulation element of this patent on the gas-liquid mixing and mass transfer was illustrated by comparison. The results are as Figure 9 and Figure 10 shown.

[0073] As Figure 9 shown, for the porous aeration disc 1, when this patent equipment was not used, the dissolved oxygen increased from 2.00 mg / L to 6.50 mg / L, which took a total of 3.77 minutes. After using this patent equipment, the corresponding time was 2.57 minutes. It can be calculated that the oxygenation time was shortened by 31.83%, and the KLa (dissolved oxygen transfer coefficient) increased by 45.50%. As Figure 10 shown, for the porous aeration disc 2, when this patent equipment was not used, the dissolved oxygen increased from 2.00 mg / L to 6.00 mg / L, which took a total of 6.50 minutes. After using this patent equipment, the corresponding time was 5.34 minutes. It can be calculated that the oxygenation time was shortened by 17.85%, and the KLa increased by 23.20%. The above data show that after using this equipment, the oxygenation efficiency has been greatly improved, which will greatly save the driving energy consumption of the pressurized air source.

[0074] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention.

Claims

1. A microporous bubbling aeration two-stage oscillation modulation efficiency enhancement system, characterized in that, It includes a two-stage oscillation device (6), a gas supply unit connected upstream of the two-stage oscillation device (6), and a microporous coil (7) and an aeration tank (8) connected downstream of the two-stage oscillation device (6); The two-stage oscillation device (6) includes an air inlet section (61), a branch section (62) connected to one side of the air inlet section (61), a non-feedback oscillation chamber (63) connected to the branch section (62), a sound wave oscillation chamber (64) connected in series with the air inlet section (61), a connecting chamber section (65) connected in parallel with the non-feedback oscillation chamber (63) and the sound wave oscillation chamber (64), and an air outlet section (66) connected in series with the outlet of the sound wave oscillation chamber (64); the air outlet section (66) is connected to the microporous coil (7) downstream; The non-feedback oscillation chamber (63) includes a non-feedback chamber air inlet section (631) connected in series with the branch section (62), a non-feedback chamber contraction pipe section (632) connected to the non-feedback chamber air inlet section (631), a non-feedback chamber double-port gas supply section (633) connected in series with the non-feedback chamber contraction pipe section (632), a counter-oscillation main chamber (634) connected to the non-feedback chamber double-port gas supply section (633), and a non-feedback chamber outlet shunt section (635) connected after the counter-oscillation main chamber (634); the non-feedback chamber outlet shunt section (635) is connected in parallel with the sound wave oscillation chamber (64) through the connecting chamber section (65).

2. The microporous bubbling aeration two-stage oscillation modulation efficiency enhancement system according to claim 1, wherein The gas supply unit includes a gas supply source (1) connected through a pipeline (5), a valve (2) installed on the pipeline (5) downstream of the gas supply source (1), a pressure regulating filter (3) installed downstream of the valve (2), and a flowmeter (4) installed downstream of the pressure regulating filter (3); The two-stage oscillation device (6) is correspondingly installed on the pipeline (5) downstream of the flowmeter (4).

3. The dual-stage oscillation modulation efficiency enhancement system for microporous bubbling aeration according to claim 2, characterized in that, The air inlet section (61) is the main pipeline, and the main pipeline is connected in series with the pipeline (5) downstream of the flowmeter (4); a branch section (62) is arranged on one side of the main pipeline; the pipe width or diameter of the branch section (62) is not greater than the width or diameter of the main pipeline; the flow rate of the branch section (62) accounts for 3%-8% of the flow rate of the air inlet section (61).

4. The microporous bubbling aeration two-stage oscillation modulation efficiency enhancement system according to claim 3, characterized in that, The non-feedback chamber air inlet section (631) is tapered, and the outlet width or diameter of the non-feedback chamber air inlet section (631) corresponds to the width or diameter of the non-feedback chamber contraction pipe section (632); the contraction angle of the non-feedback chamber air inlet section (631) with the horizontal line is between 12 and 17 degrees, and the inlet width is selected according to the standard thread diameter; The length of the non-feedback chamber air inlet section (631) is greater than or equal to 2 times the length of the non-feedback chamber contraction pipe section (632); the non-feedback chamber contraction pipe section (632) is a straight pipe, and its length is 3 to 4 times the width or diameter, and the width or diameter is 1 / 3 to 1 / 2 of the width or diameter at the inlet of the non-feedback chamber air inlet section (631).

5. The dual-stage oscillation modulation and efficiency enhancement system for microporous bubbling aeration according to claim 4, wherein The non-feedback chamber double-port gas supply section (633) is divided into two parts from the non-feedback chamber contraction pipe section (632) in series and symmetrically enters the counter-oscillation main chamber (634); the non-feedback chamber double-port gas supply section (633) is divided into a straight section and an arc section on one side, the straight section is tapered, and the arc section is of equal width or diameter, and the width or diameter of the arc section corresponds to the width or diameter of the outlet of the straight section; The distance from the vertex of the shunt wedge in the double-port air supply section (633) of the non-feedback cavity to the end of the contraction pipe section (632) of the non-feedback cavity is 4 to 8 times the width of the double-port air supply section (633) of the non-feedback cavity.

6. A microbubble aeration two-stage oscillation modulation and efficiency enhancement system according to claim 5, characterized in that The counter-oscillation main cavity (634) is in the shape of an elliptical box, and the angle between the double-port air supply section (633) of the non-feedback cavity connected to the counter-oscillation main cavity (634) and the horizontal line is 25 to 35 degrees; O is the center of the oscillation cavity, H1 is the straight-line distance from the center of the oscillation cavity to the upstream cavity wall, H2 is the straight-line distance from the center of the oscillation cavity to the outlet of the downstream cavity, L0 is the distance between the inlets of the two double-port air supply sections (633) of the non-feedback cavity, L1 is the distance from the inlet of the double-port air supply section (633) of the non-feedback cavity to the center of the cavity, L2 is the distance of the outlet straight section, W1 is the width or diameter at the outlet of the arc section of the double-port air supply section (633) of the non-feedback cavity; W2 is the outlet width or diameter; The parameters are set as: H1 is 5 to 6 times W1, H2 is 4.0 to 4.5 times W1, L0 is 9 to 11 times W1, L1 is 6 to 8 times W1, L2 is 2.5 to 3.5 times W1, and W2 is 1.8 to 2.5 times W1; The non-feedback cavity outlet shunt section (635) is bifurcated into two parts in a V shape at the connection with the counter-oscillation main cavity (634); the angle O1 between the outer side of each outlet edge and the horizontal line is 18 to 25 degrees, and the angle O2 between the inner side and the horizontal line is 12 to 19 degrees; and the outlet on each side is arranged in a gradually expanding shape; The distance H3 from the bifurcation point at the connection to the outlet of the counter-oscillation main cavity (634) is 4 to 9 times W2, and the bifurcation point is smoothly set.

7. A microporous bubbling aeration two-stage oscillation modulation efficiency enhancement system according to claim 6, characterized in that, The acoustic oscillation cavity (64) includes an acoustic cavity inlet section (641) connected to the air inlet section (61), an acoustic oscillation feedback cavity (642) connected downstream of the acoustic cavity inlet section (641), and an acoustic cavity outlet section (643) connected in sequence downstream of the acoustic oscillation feedback cavity (642); The acoustic cavity inlet section (641) includes a gradually changing contraction pipe and a throat pipe, and the contraction angle β of the gradually changing contraction pipe is 10 to 15 degrees; the width or diameter of the throat pipe is W3, which is 9 to 12 times W1, and the length of the throat pipe is L3, and the length of L3 is 3 to 4 times W3; The acoustic oscillation feedback cavity (642) is symmetrically shaped like a water droplet, the angle γ between the acoustic oscillation feedback cavities (642) on both sides of the acoustic cavity inlet section (641) is 10 to 15 degrees, and the width near the throat of the acoustic oscillation feedback cavity (642) is 0.5 to 0.9 times W3.

8. A microporous bubbling aeration two-stage oscillation modulation synergistic system according to claim 7, characterized in that The acoustic cavity outlet section (643) is arranged in the middle of the two acoustic oscillation feedback cavities (642) and the shunt wedge is divided into two outlet channels. The distance P between the two top points of the shunt wedge is 1.5 to 3 times W3, the distance H4 from the tip of the shunt wedge to the middle outlet of the acoustic oscillation feedback cavity (642) is 4 to 11 times the throat width W3, and the radius of the shunt wedge is 0.1 to 2 times W3; The angle O1 between the outer side of each side of the acoustic cavity outlet section (643) and the horizontal line is 18 to 25 degrees, and the angle O2 between the inner side and the horizontal line is 12 to 19 degrees.

9. The dual-stage oscillation modulation and efficiency enhancement system for microporous bubble aeration according to claim 8, wherein, There are two connected cavity segments (65). One connected cavity segment (65) connects one outlet side of the non-feedback cavity outlet shunt segment (635) and one outlet side of the sound wave cavity outlet segment (643); the other connected cavity segment (65) connects the other outlet side of the non-feedback cavity outlet shunt segment (635) and the other outlet side of the sound wave cavity outlet segment (643).

10. A method for applying the microporous bubbling aeration two-stage oscillation modulation enhancement system according to claim 9, characterized in that, The specific steps are as follows: Step 1: Supply air through the air supply source (1), and control the air flow velocity and flow rate through the valve (2) and the pressure regulating filter (3); then the air flow enters the intake section (61) of the double-stage oscillation device (6) through the pipeline (5); Step 2: The air flow is shunted from the intake section (61) to the branch section (62), and the air flow enters the non-feedback cavity intake section (631), passes through the non-feedback cavity contraction pipe section (632) and the non-feedback cavity double-port air supply section (633) and enters the counter-jet oscillation main cavity (634); Step 3: After the air flow enters the counter-jet oscillation main cavity (634), initially the main jet does not show an offset phenomenon, the flow field remains uniformly distributed and flows out uniformly from the two non-feedback cavity outlet shunt segments (635); immediately, one of the two supply jets coming in from both sides of the inlet establishes a main connection with the outlet of the counter-jet oscillation main cavity (634) and jets out in the forward direction, and the other supply jet forms a vortex area inside the circular cavity of the counter-jet oscillation main cavity (634); Step 4: Due to the turbulence and entrainment effect of the jet itself, and affected by the shunt splitter, the previous equilibrium state is affected, and a pressure difference appears on both sides of the shunt splitter. When the pressure difference reaches a certain order of magnitude, the jet starts to tilt and deflect towards the lower side wall with lower pressure, and at the same time, a stable wall attachment phenomenon appears, and it flows out along the outlet pipe on this side at a speed higher than that of the other side wall; Step 5: Subsequently, since the vortex area inside the circular cavity is large enough and collides with the jet at the action point, the main connection between the jet and the circular cavity outlet is broken and a new vortex area is gradually formed inside the circular cavity, prompting the other supply jet to establish a main connection with the circular cavity outlet and jet out in the negative direction. At this time, due to the inherent turbulence and entrainment effect of the jet itself, a pressure difference relationship opposite to the previous one appears on both side walls of the shunt splitter, resulting in the jet deflecting towards the upper side wall and flowing out along the outlet pipe on this side wall at a high speed, and one switching is completed; finally, due to the action of a different internal vortex area in the previous stage, the initial supply jet re-establishes a main connection with the circular cavity outlet, and the jet also correspondingly switches and attaches to the lower side wall; the occurrence of oscillation stems from the interaction between the two jets in the circular cavity, and the continuation of oscillation stems from the periodic wall attachment switching behavior of the jet. Step Six: After the air flow in the intake section (61) enters the acoustic oscillation cavity (64), the boundary layer separation effect causes low-pressure eddy regions to form on both sides of the jet; the pressure value of the low-pressure eddy region on one side is higher, pushing the main jet to the other side and attaching it to the wall; the pressure reduction on the non-attached wall side causes a large amount of air flow to be entrained on this side. At the same time, the pulsating jet from the outlet of the non-feedback oscillation cavity (63) intermittently applies fluctuating pressure through the feedback pipes on both sides of the main jet in the acoustic oscillation cavity (64). Coupled with the entrainment effect, the pressure on the attached wall side rises rapidly. After exceeding the non-attached wall side, the main jet is pushed back to form a new attached wall side, thus completing the switching of half a cycle; Similarly, on the new attached wall side, which was the previous non-attached wall side, "entrainment - push - switch" occurs, completing the switching of the entire cycle; such a cyclic "attachment - entrainment - switch" periodic motion causes the incoming main jet to flow out rapidly and alternately along the two outlets, forming a high-frequency pulsed oscillating flow; Step Seven: Based on the high-frequency pulsed oscillating flow formed in the acoustic oscillation cavity, the gas flows out from the outlet section (643) of the acoustic cavity and is successively connected to the microporous coiled pipe (7) and the aeration tank (8), thereby completing the application of the microporous bubble aeration two-stage oscillation modulation and efficiency enhancement system.

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