Acoustic field enhancement based flat sheet membrane mass transfer internals, trapping tower and trapping system

Abstract

This invention discloses a planar membrane mass transfer internal component, a collection tower, and a collection system based on sound field enhancement. The planar membrane mass transfer internal component includes several vertically arranged resonant composite plates and a support assembly for supporting the resonant composite plates. The resonant composite plates are layered structures with double-sided mass transfer, comprising, from the inside out, a piezoelectric transducer array layer, an acoustic impedance matching layer, and a hydrophilic microporous mass transfer layer. The piezoelectric transducer array layer is electrically connected to a power supply to generate high-frequency mechanical vibration, thereby forming a high-frequency sound field. The support assembly includes several limiting grooves located above and below the resonant composite plates, and a frame for fixing the limiting grooves. The resonant composite plates are floatingly installed within the limiting grooves, with their upper and lower ends forming a limiting fit with the limiting grooves. This invention significantly improves mass transfer efficiency by disrupting the boundary layer of high-viscosity liquid films at the microscale using active sound field technology, and solves the problem of fixing and damping piezoelectrically brittle components in industrial towers by employing a floating installation structure.

Description

Technical Field

[0001] This invention belongs to the field of chemical separation and mass transfer equipment technology, specifically relating to a flat sheet membrane mass transfer internal, a collection tower and a collection system based on sound field enhancement. Background Technology

[0002] In industrial waste gas treatment, the traditional alkanolamine absorption method, while mature, remains hampered by high energy consumption and solvent evaporation for capturing acidic gases such as carbon dioxide (CO2) and hydrogen sulfide (H2S). Ionic liquids and eutectic solvents, with their advantages of low vapor pressure and good thermal stability, show promising application prospects. Chemical-physical composite absorbents, on the other hand, combine high chemical absorption capacity, low energy consumption for physical absorption and regeneration, and low volatility, making them a current research hotspot. However, both types of absorbents have significant physical limitations: their viscosity is often much higher than that of aqueous absorbents. This high viscosity creates an extremely stable laminar boundary layer at the gas-liquid interface, severely hindering the diffusion of gas molecules into the deeper liquid phase, thus limiting gas-liquid mass transfer efficiency. In engineering, this often necessitates a significant increase in equipment volume to compensate for the insufficient rate.

[0003] Existing industrial desulfurization and decarbonization devices mostly employ improvements at the fluid dynamics level. One approach is passive enhancement at the fluid dynamics level, such as patent CN118681394A, which increases the macroscopic contact area through a combination of multi-stage atomized spraying and corrugated packing. However, simple macroscopic turbulence is insufficient to penetrate the microscopic laminar sublayer, and the liquid deep within the liquid film cannot be replenished to the interface in a timely manner. Another approach is active enhancement by introducing mechanical energy, such as patent CN118142323A, which uses a motor to drive an internal rotating component to agitate the gas-liquid flow field. Although mechanical stirring can improve local mixing, when processing acidic gases, the complex transmission components are exposed to a corrosive environment for extended periods, easily leading to seal failure and wear, resulting in high maintenance costs. More importantly, mechanical stirring primarily acts on the macroscopic fluid domain, making it difficult to implement within precise flat-panel membrane modules, and it cannot precisely control the micron-level interfacial boundary layer.

[0004] Therefore, in flat-panel membrane contactors, which are devices with high specific surface area, there is currently a lack of non-contact technologies that can actively disrupt the liquid film boundary layer and induce surface renewal. Summary of the Invention

[0005] This invention aims to solve the problem of hindered surface renewal and high mass transfer resistance caused by an excessively thick laminar boundary layer in the liquid film when capturing acidic gases using high-viscosity absorbents. It also overcomes the limitations of existing mechanical enhancement methods, such as complex structures, high energy consumption, and difficulty in achieving precise microscopic flow field control. To this end, this invention provides a planar membrane mass transfer internal component, a capture tower, and a capture system that uses a piezoelectric array to drive acoustic field enhancement. By employing active acoustic field technology to disrupt the laminar layer of the liquid film at the microscopic scale, it improves gas-liquid mass transfer efficiency.

[0006] To achieve the above objectives, a first aspect of the present invention provides a planar membrane mass transfer internal device based on sound field enhancement, comprising:

[0007] The flat-plate membrane mass transfer internals include a plurality of vertically arranged resonant composite plates and a support assembly for supporting the resonant composite plates. A gas flow channel is formed between adjacent resonant composite plates, wherein:

[0008] The resonant composite plate is a layered structure with double-sided mass transfer, which includes, from the inside out, a piezoelectric transducer array layer, an acoustic impedance matching layer, and a hydrophilic microporous mass transfer layer; the piezoelectric transducer array layer is electrically connected to the power supply and is used to generate high-frequency mechanical vibration, thereby forming a high-frequency sound field;

[0009] The support assembly includes limiting grooves located above and below the resonant composite plate, and a frame for fixing the limiting grooves; the resonant composite plate is floatingly installed in the limiting grooves, and its upper and lower ends form limiting fits with the limiting grooves.

[0010] In some embodiments, the piezoelectric transducer array layer includes a plurality of piezoelectric vibration units and conductive wires. The piezoelectric vibration units are arranged in a matrix on a two-dimensional plane, and the piezoelectric vibration units are electrically connected to each other through conductive wires. The piezoelectric vibration units are selected from one or more of PZT-5H type piezoelectric ceramic wafers, PZT-4 type piezoelectric ceramic wafers, PZT-8 type piezoelectric ceramic wafers, and lead-free piezoelectric ceramic materials.

[0011] In some embodiments, the acoustic impedance matching layer covers the outside of the piezoelectric transducer array layer to form an insulating encapsulation structure; the acoustic impedance value of the acoustic impedance matching layer is between that of the piezoelectric transducer array layer and the absorbent in contact with the hydrophilic microporous mass transfer layer.

[0012] In some embodiments, the hydrophilic microporous mass transfer layer has a smooth, flat surface, a thickness of 10 μm to 200 μm, preferably 50 μm to 100 μm, and an average pore size of 0.05 μm to 2.0 μm, preferably 0.1 μm to 0.5 μm. The hydrophilic microporous mass transfer layer is a hydrophobic or hydrophilic membrane, the specific type of which can be selected according to the wetting characteristics of the absorbent. The hydrophobic membrane is selected from one or more of polytetrafluoroethylene microporous membranes, polyvinylidene fluoride microporous membranes, and polyimide microporous membranes. The hydrophilic membrane is selected from one or more of plasma-modified polytetrafluoroethylene microporous membranes, plasma-modified polyvinylidene fluoride microporous membranes, plasma-modified polyimide microporous membranes, and hydrophilic porous ceramic membranes.

[0013] In some embodiments, the top of the resonant composite plate is embedded with an acoustic energy driving interface; the conductive wires of the piezoelectric transducer array layer converge at the acoustic energy driving interface, and corrosion-resistant flexible leads are led out from the acoustic energy driving interface to connect to the power supply.

[0014] In some embodiments, the support assembly has a filter plate disposed between the limiting grooves located below the resonant composite plate; a corrosion-resistant elastic damping element is disposed within the limiting groove.

[0015] A second aspect of the present invention is to provide a trapping tower employing the above-described flat-plate membrane mass transfer internals, the trapping tower comprising a tower body, wherein at least one layer of the flat-plate membrane mass transfer internals is arranged vertically inside the tower body; the frame of the support assembly of the flat-plate membrane mass transfer internals is fixedly connected to the inner wall of the tower body; the trapping tower is provided with a raw material inlet, a purified gas outlet, a lean liquid inlet, and a rich liquid outlet; the trapping tower is provided with a liquid distributor communicating with the lean liquid inlet at the upper part of the flat-plate membrane mass transfer internals, and the liquid outlet of the liquid distributor is located directly above the gas flow channel formed between adjacent resonant composite plates;

[0016] The outer wall of the tower body is provided with airtight through-wall connection terminals at positions corresponding to each layer of the resonant composite plate; the piezoelectric transducer array layer of the plate membrane mass transfer internals is connected to the power supply via the airtight through-wall connection terminals.

[0017] The third invention is to provide a collection system employing the above-mentioned collection tower, the collection system comprising a collection tower, a regeneration unit and an intelligent sound field control unit;

[0018] The regeneration unit is connected to the rich liquid outlet and the lean liquid inlet of the collection tower via pipelines.

[0019] The intelligent sound field control unit includes an online monitoring module, a central processing unit, and a power supply;

[0020] The online monitoring module is installed on the pipeline at the outlet of the rich liquid and is used to detect the dynamic viscosity μ and temperature T of the rich liquid in real time, and transmit the viscosity signal and temperature signal to the central processing unit.

[0021] The central processing unit integrates a multi-channel signal generator, a PID feedback control algorithm, and an absorbent property database, used to generate a dynamic viscosity threshold μ based on the absorbent type currently in operation and its real-time temperature T. set The dynamic viscosity threshold μ set Determined by the following formula:

[0022] μ set =μ0(T) ×(1+k)

[0023] Wherein, μ0(T) is the basic dynamic viscosity of the absorbent used in the collection system at temperature T for fresh lean liquid, and k is a preset viscosity change critical coefficient; the viscosity change critical coefficient k is a dimensionless empirical parameter, the value of which is determined by the rheological properties of the absorbent system and the acid gas loading.

[0024] The central processing unit is also used to obtain the dynamic viscosity μ and the dynamic viscosity threshold μ from the online monitoring module. set The comparison is performed, and a drive adjustment command containing the target frequency f and the target voltage amplitude V is output to the power supply based on the comparison result;

[0025] The power supply is electrically connected to the piezoelectric transducer array layer in the resonant composite plate, and is used to adjust the output frequency and output voltage amplitude according to the driving adjustment command, so as to adjust the vibration intensity and vibration frequency of the piezoelectric transducer array layer and realize dynamic closed-loop control of the sound field.

[0026] In some embodiments, the central processing unit of the intelligent sound field control unit executes the following control logic:

[0027] The dynamic viscosity μ monitored by the online monitoring module is compared with the dynamic viscosity threshold μ calculated by the central processing unit. set Compare;

[0028] When the dynamic viscosity μ is lower than the dynamic viscosity threshold μ set When the power supply outputs a corresponding drive signal, the piezoelectric transducer array layer enters the energy-saving mode.

[0029] When the dynamic viscosity μ is higher than the dynamic viscosity threshold μ set At that time, the power supply is controlled to output a corresponding drive signal, causing the piezoelectric transducer array layer to enter the enhancement mode.

[0030] In some embodiments, in the energy-saving mode, the intelligent sound field control unit controls the power supply to output a low-power-density intermittent pulse drive signal; in the enhancement mode, the intelligent sound field control unit controls the power supply to output a high-power-density continuous drive signal, and controls the power supply to automatically sweep frequencies within a preset frequency range to lock the optimal resonant frequency.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] (1) This invention integrates a piezoelectric array inside a flat sheet membrane, mainly utilizing the strong acoustic flow effect and shear thinning effect induced by the high-frequency acoustic field at the microscale, and in conjunction with the local microcavitation effect, actively destroys the thick laminar flow boundary layer formed by high-viscosity solvent, changing the mass transfer control step from molecular diffusion to convective diffusion, thereby improving the gas-liquid mass transfer coefficient of high-viscosity fluid.

[0033] (2) By utilizing the shear thinning effect of high-frequency sound field, the apparent viscosity of high-viscosity solvents such as chemical-physical composite solvents is effectively reduced, which greatly improves their spreading coefficient on the microporous surface and solves the problem of poor wettability and easy channeling of high-viscosity liquids in traditional packed towers.

[0034] (3) The system integrates an intelligent sound field control unit, which can dynamically adjust the sound energy input according to the real-time rheological state of the solvent. Compared with traditional equipment with constant power, the present invention only releases high-energy sound fields during periods when the solvent viscosity is high and the mass transfer resistance is high, thereby achieving optimal energy management while ensuring mass transfer efficiency.

[0035] (4) Compared with the mechanical rotating parts used in the prior art, the piezoelectric transducer array layer of the present invention is encapsulated inside the plate, which is a non-contact reinforcement with no moving parts. This avoids mechanical wear and dynamic seal leakage risks in corrosive acidic gas environments and can effectively extend the service life of the equipment. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the process flow of the collection system of the present invention.

[0037] Figure 2 This is a schematic cross-sectional view of the resonant composite plate in this invention.

[0038] Figure 3 This is a schematic diagram of the planar arrangement of the piezoelectric transducer array layer in this invention.

[0039] Figure 4 This is a schematic diagram of the microscopic mass transfer mechanism on the surface of a liquid film under the influence of an acoustic field.

[0040] Figure 5 This is a schematic diagram of the support component in this invention.

[0041] Figure 6 This is a schematic diagram of the fixed assembly of the resonant composite plate in this invention.

[0042] Figure 7 This is a flowchart of the control logic of the intelligent sound field control unit in this invention.

[0043] In the diagram: 100 - Resonant composite plate; 110 - Piezoelectric transducer array layer; 111 - Piezoelectric vibration unit; 112 - Conductive wire; 120 - Acoustic impedance matching layer; 130 - Hygrophilic microporous mass transfer layer; 140 - Acoustic energy drive interface; 150 - Corrosion-resistant flexible lead wire; 160 - Corrosion-resistant shielded main cable; 170 - Airtight through-wall connection terminal; 200 - Support component; 210 - Limiting groove; 220 - Frame; 230 - Filter plate; 240 - Corrosion-resistant elastic damping component; 300 - Power supply; 400 - Collection tower; 410 - Tower body; 411 - Raw material inlet; 412 - Purified gas outlet; 413 - Lean liquid inlet; 414 - Rich liquid outlet; 420 - Liquid distributor; 500 - Regeneration unit; 600 - Online monitoring module; 700 - Central processing unit. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0045] Example 1: Structural Construction of a Flat Sheet Membrane Mass Transfer Internals Based on Acoustic Field Enhancement

[0046] This embodiment is used to illustrate the microstructure, mechanical mounting structure and electrical connection process of the flat sheet membrane mass transfer internals.

[0047] like Figure 1 and Figure 2 As shown, the flat membrane mass transfer internals include a plurality of vertically arranged resonant composite plates 100, and a support assembly 200 for supporting the resonant composite plates 100. Gas flow channels are formed between adjacent resonant composite plates 100, wherein:

[0048] The resonant composite plate 100 is a layered structure with double-sided mass transfer. From the inside to the outside, the resonant composite plate 100 includes a piezoelectric transducer array layer 110, an acoustic impedance matching layer 120, and a hydrophilic microporous mass transfer layer 130. The piezoelectric transducer array layer 110 is connected to a power supply 300 and is used to generate high-frequency mechanical vibrations perpendicular to the plate surface, thereby forming a high-frequency sound field. The hydrophilic microporous mass transfer layer 130 is used to receive liquid, and the acoustic impedance matching layer 120 is used to transfer acoustic energy to the liquid on the surface of the hydrophilic microporous mass transfer layer 130.

[0049] The gas to be treated flows from bottom to top in the gas flow channel, and the high-viscosity absorbent is sprayed from top to bottom onto the surface of the resonant composite plate 100, forming a liquid film that flows vertically downward along the plate surface. Utilizing the physical advantages of gravity-induced film flow, combined with the acoustic viscosity reduction effect of the high-frequency sound field generated by the piezoelectric transducer array layer 110, the spreading coefficient and flow velocity of the high-viscosity absorbent on the surface of the hydrophilic microporous mass transfer layer 130 are effectively improved. This can significantly prevent liquid film stagnation and channeling, ensuring the uniformity and efficiency of gas-liquid mass transfer.

[0050] Combination Figure 3 As shown, the piezoelectric transducer array layer 110 is located at the center of the resonant composite plate 100, and includes several piezoelectric vibration units 111 and conductive wires 112. The piezoelectric vibration units 111 are arranged in a matrix on a two-dimensional plane, and each piezoelectric vibration unit 111 is electrically connected in parallel through conductive wires 112. This array design ensures the uniformity of the sound field on the entire plate surface.

[0051] Furthermore, the piezoelectric transducer array layer 110 may be one or more of PZT-5H type piezoelectric ceramic wafers, PZT-4 type piezoelectric ceramic wafers, PZT-8 type piezoelectric ceramic wafers, and lead-free piezoelectric ceramic materials; the conductive wires 112 may be configured as an embedded flexible circuit network.

[0052] The acoustic impedance matching layer 120 is fully coated on the outside of the piezoelectric transducer array layer 110, and its material is preferably modified epoxy resin doped with tungsten powder. The acoustic impedance value of the acoustic impedance matching layer 120 is precisely adjusted to be between that of the piezoelectric transducer array layer 110 and the absorbent in contact with the hydrophilic microporous mass transfer layer 130, so as to not only serve as an insulating encapsulation, but also minimize sound wave reflection and efficiently transfer sound energy to the outer layer.

[0053] The outermost hydrophilic microporous mass transfer layer 130 has a smooth, flat surface and a thickness of 10 μm to 200 μm, preferably 50 μm to 100 μm, with an average pore size of 0.05 μm to 2.0 μm, preferably 0.1 μm to 0.5 μm. The hydrophilic microporous mass transfer layer 130 is a hydrophobic or hydrophilic membrane, and its specific type can be selected according to the wetting characteristics of the absorbent. The hydrophobic membrane is selected from one or more of polytetrafluoroethylene microporous membranes, polyvinylidene fluoride microporous membranes, and polyimide microporous membranes. The hydrophilic membrane is selected from one or more of plasma-modified polytetrafluoroethylene microporous membranes, plasma-modified polyvinylidene fluoride microporous membranes, plasma-modified polyimide microporous membranes, and hydrophilic porous ceramic membranes. The aforementioned hydrophilic microporous mass transfer layer 130 has excellent wettability, can receive liquids from top to bottom, and form a liquid film on its surface under the combined effect of gravity and surface tension, and maintain the stable flow of the liquid film.

[0054] like Figure 4 As shown, when the piezoelectric transducer array layer 110 is energized and generates high-frequency mechanical vibration, the vibration is efficiently transmitted to the hydrophilic microporous mass transfer layer 130 and its surface liquid film through the acoustic impedance matching layer 120, thereby enhancing the gas-liquid mass transfer process at the microscale. The specific mechanism is as follows:

[0055] (S1) The radiation pressure generated by the sound wave at the gas-liquid interface triggers the acoustic flow effect, inducing acoustic flow vortices with a scale of micrometers inside the liquid film. Forced convection directly disrupts the laminar boundary layer closely attached to the gas-liquid interface, entraining the saturated solvent at the interface to the depths, while simultaneously transporting fresh solvent from the depths to the interface, thus accelerating the surface renewal rate.

[0056] (S2) The high-intensity ultrasonic vibration field generates high-frequency shear force inside the liquid. In the area where the sound field acts, the apparent viscosity of the absorbent is temporarily reduced, making the liquid film spread more evenly and thinner on the surface of the micropores, and increasing the effective gas-liquid contact area.

[0057] (S3) In micro-regions where the apparent viscosity decreases due to the shear thinning effect described above and the sound pressure exceeds the cavitation threshold, the generation and collapse of micro-cavitation bubbles can be induced. Although the overall cavitation threshold of the high-viscosity absorbent is high, the micro-jet and shock wave generated at the moment of cavitation bubble collapse, under the synergistic effect of high-frequency acoustic flow and local viscosity reduction, can still further intensify the micro-turbulence of the liquid film, providing additional mass transfer enhancement for the dissolution and reaction process of gas molecules passing through the gas-liquid interface.

[0058] Combination Figure 5 and Figure 6 As shown, the resonant composite plate 100 forms a stable vertical parallel plate-type falling film structure through the support component 200, which supports the lower part of the plate. Specifically, the support component 200 includes several limiting grooves 210 located above and below the resonant composite plate 100, and a frame 220 for fixing the limiting grooves 210. The resonant composite plate 100 is floatingly installed within the limiting grooves 210, with its upper and lower ends forming a clearance fit with the limiting grooves 210. Preferably, a corrosion-resistant elastic damping element 240 (such as a perfluoroether rubber sealing ring or a polytetrafluoroethylene gasket) is also provided within the limiting groove 210 to form a flexible buffer support. This floating installation design allows the resonant composite plate 100 to undergo slight displacement in the vertical and horizontal directions due to thermal expansion and contraction or high-frequency vibration, eliminating thermal and mechanical stress, avoiding rigid collisions between the resonant composite plate 100 and the limiting grooves 210, solving the engineering problem of the fragility of brittle piezoelectric ceramics, and reducing the ineffective transmission of sound energy to the frame 220.

[0059] The above-mentioned flat membrane mass transfer internals can be arranged in one or more layers in the vertical direction. When multiple layers are arranged, preferably, the support assembly 200 is also provided with a filter plate 230 between the limiting grooves 210 located below the resonant composite flat plate 100. The filter plate 230 not only allows the liquid to pass through and flow to the next layer, but also plays a role in liquid redistribution, ensuring that the liquid drips evenly to the lower internals.

[0060] This embodiment employs a fully encapsulated embedded electrical connection design to ensure the flatness of the flat panel surface and adapt to the spraying environment of the board. Specifically, as shown... Figures 2 to 4 As shown, the top of the resonant composite plate 100 is embedded with an acoustic energy drive interface 140 using an integrated molding process. The conductive wires 112 of the piezoelectric transducer array layer 110 converge at the acoustic energy drive interface 140, and a corrosion-resistant flexible lead 150 is led out from the acoustic energy drive interface 140 to connect to the power supply 300. The lead-out portion of the corrosion-resistant flexible lead 150 is encapsulated with high-performance epoxy resin to form a completely sealed protective structure, ensuring complete isolation of the piezoelectric transducer array layer 110 from the external environment. Through the above-mentioned embedded interface design, the acoustic energy drive interface 140 is completely hidden inside the resonant composite plate 100 body, ensuring that the streamlined structure of the plate surface is not damaged and effectively avoiding disturbance to the descending liquid film.

[0061] Example 2, Collection Tower

[0062] This embodiment demonstrates the structure of a trapping tower employing the flat-sheet membrane mass transfer internals of Embodiment 1 described above.

[0063] like Figure 1 and Figure 5 As shown, the trapping tower 400 includes a tower body 410, and at least one layer of the flat sheet membrane mass transfer internals is arranged vertically inside the tower body 410; the frame 220 of the support assembly 200 of the flat sheet membrane mass transfer internals is fixedly connected to the inner wall of the tower body 410; the trapping tower 400 is provided with a raw material inlet 411, a purified gas outlet 412, a lean liquid inlet 413, and a rich liquid outlet 414; the trapping tower 400 is also provided with a liquid distributor 420 communicating with the lean liquid inlet 413 at the upper part of the flat sheet membrane mass transfer internals.

[0064] To ensure efficient wetting of the plate surface by high-viscosity liquid and reduce splashing, the liquid distributor 420 is optimized in this embodiment. The liquid outlet at the bottom of the liquid distributor 420 is precisely arranged, preferably positioned directly above the gas flow channel formed between adjacent resonant composite plates 100. During operation, the liquid is sprayed into the inter-plate channel in a fan or cone shape and adheres to the surface of the hydrophilic microporous mass transfer layer 130 on both sides. Since it does not need to pass through the top plane of the plate, ineffective accumulation and splashing loss of liquid on the top of the plate are avoided. In addition, the liquid outlet of the liquid distributor 420 and the acoustic drive interface 140 located on the top of the resonant composite plate 100 are staggered in horizontal projection position, and the liquid flow path and electrical lead-out point are naturally separated in space, further ensuring safety.

[0065] The absorbent (such as a high-viscosity chemical-physical composite solvent) enters the tower from the lean liquid inlet 413 at the top of the tower, and is precisely sprayed onto the surface of the resonant composite plate 100 by the liquid distributor 420. It forms a liquid film along the vertical plate surface and flows down to the next layer or the bottom of the tower. The feed gas enters from the feed gas inlet 411 at the bottom of the tower, flows upward in the gas flow channel between two adjacent resonant composite plates 100, and undergoes countercurrent contact mass transfer with the liquid film surface. It is then discharged from the purified gas outlet 412.

[0066] This embodiment employs a flexible connection scheme to adapt to the vibration environment. Specifically, the collection tower 400 is equipped with airtight through-wall connection terminals 170 at positions corresponding to each layer of the resonant composite plate 100. The corrosion-resistant flexible lead wire 150 at the top of each resonant composite plate 100 is led out and bundled together inside the tower using acid-resistant cable ties, connecting to a corrosion-resistant shielded main cable 160. This corrosion-resistant shielded main cable 160 is then connected to the inner side of the airtight through-wall connection terminal 170 on the tower wall. The outer side of the airtight through-wall connection terminal 170 is connected to the power supply 300 via an aviation plug, enabling reliable transmission of control signals to the enclosed environment inside the tower.

[0067] Furthermore, the airtight through-wall connection terminal 170 preferably adopts a high-pressure resistant glass-metal sealing or ceramic-metal brazing structure. To resist the corrosion of acidic gases inside the tower, the contact pins of the airtight through-wall connection terminal 170 located on the inner side of the tower are made of Hastelloy alloy or have a gold-plated surface; its insulating medium is selected from chemically corrosion-resistant special electronic ceramics or polyetheretherketone materials. The airtight through-wall connection terminal 170 is fixed to the tower wall through a standard flange interface and is statically sealed with a PTFE-coated metal O-ring.

[0068] Example 3: High-viscosity solvent acid gas capture system with intelligent feedback function

[0069] This embodiment demonstrates a high-viscosity solvent acid gas capture system with intelligent feedback function and its control logic using the capture tower of Embodiment 2 described above.

[0070] like Figure 1 As shown, the collection system includes a collection tower 400, a regeneration unit 500, and an intelligent sound field control unit;

[0071] The regeneration unit 500 is connected to the rich liquid outlet 414 and the lean liquid inlet 413 of the collection tower 400 through pipelines to realize the regeneration and circulation of the absorbent.

[0072] The intelligent sound field control unit includes an online monitoring module 600, a central processing unit 700, and a power supply 300;

[0073] The online monitoring module 600 is installed on the pipeline of the rich liquid outlet 414 and is used to detect the dynamic viscosity μ and temperature T of the rich liquid in real time, and transmit the viscosity signal and temperature signal to the central processing unit 700.

[0074] The central processing unit 700 integrates a multi-channel signal generator, a PID feedback control algorithm, and an absorbent property database, used to generate a dynamic viscosity threshold μ based on the type of absorbent currently in operation and its real-time temperature T. set The dynamic viscosity threshold μ set Determined by the following formula:

[0075] μ set =μ0(T) ×(1+k)

[0076] Where μ0(T) is the basic dynamic viscosity of the absorbent used in the trapping system at temperature T for fresh lean solution, and k is a preset viscosity change critical coefficient; the viscosity change critical coefficient k is a dimensionless empirical parameter, the value of which is determined by the rheological properties of the absorbent system and the acid gas loading. For different absorbent formulations, due to differences in their microscopic interactions, the critical loading at which viscosity change occurs is different, and therefore the applicable k value also differs. In actual industrial operation, the specific k value can be determined by pre-measuring the viscosity-mass transfer performance curves of a particular absorbent under different loadings, and its preferred range is usually 0.1~0.5.

[0077] The central processing unit 700 is also used to obtain the dynamic viscosity μ and the dynamic viscosity threshold μ from the online monitoring module 600. set The comparison is performed, and based on the comparison result, a drive adjustment command containing the target frequency f and the target voltage amplitude V is output to the power supply 300.

[0078] like Figure 7As shown, the central processing unit 700 of the intelligent sound field control unit executes the following control logic:

[0079] S1 Data Acquisition and Judgment: The dynamic viscosity μ monitored by the online monitoring module 600 is compared with the dynamic viscosity threshold μ calculated by the central processing unit 700. set Compare;

[0080] S2 Energy Saving Mode: When the dynamic viscosity μ is lower than the dynamic viscosity threshold μ set When the power supply 300 is controlled to output a corresponding drive signal, the piezoelectric transducer array layer 110 enters the energy-saving mode.

[0081] S3 Enhancement Mode: When the dynamic viscosity μ is higher than the dynamic viscosity threshold μ set At that time, the power supply 300 is controlled to output a corresponding drive signal, so that the piezoelectric transducer array layer 110 enters the enhancement mode.

[0082] In the energy-saving mode, the intelligent sound field control unit controls the power supply 300 to output a low-power-density intermittent pulse drive signal; in the enhanced mode, the intelligent sound field control unit controls the power supply 300 to output a high-power-density continuous drive signal, and controls the power supply 300 to automatically sweep frequencies within a preset frequency range to lock the optimal resonant frequency.

[0083] The aforementioned closed-loop control mechanism based on real-time rheological parameters ensures that the high-energy-consuming acoustic field enhancement is only released during the period of greatest fluid mass transfer resistance. While ensuring the overall removal efficiency, it minimizes the system's power consumption, demonstrating the intelligence and precision of process enhancement.

[0084] Example 4: High-viscosity solvent CO2 capture process under acoustic field synergy

[0085] This embodiment demonstrates the actual process and collection effect of using the collection system described in Embodiment 3 above to treat acidic gases containing CO2.

[0086] A mixture of ethanolamine and hydrophobic ionic liquid was selected as the high-viscosity absorbent in the experiment. Specifically, it was a mixed absorbent composed of 30 wt% ethanolamine (MEA) and 70 wt% 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt ([Emim][Tf₂N]). The initial dynamic viscosity of this mixed absorbent at 25 °C was approximately 40 mPa·s. During CO₂ absorption, the dynamic viscosity increased significantly due to the reaction of MEA with CO₂ to form urethane esters, which then formed complex ionic clusters and hydrogen bond networks with the ionic liquid. When the CO₂ loading reached 0.5–0.8 mol CO₂ / mol amine, the dynamic viscosity of the system rose sharply to over 80 mPa·s. The abrupt viscosity change caused by chemical absorption increased the mass transfer resistance and significantly reduced the diffusion coefficients of reactants and products.

[0087] The feed gas simulates typical flue gas from a coal-fired power plant, with a CO2 volume fraction of 15% and the remainder being N2. The gas flow rate is set to 500 Nm³. 3 / h.

[0088] The inner diameter of the tower body 410 is 0.4 m, the effective mass transfer height formed by the resonant composite plate 100 is 3.5 m, and the spacing between adjacent resonant composite plates 100 is set to 15 mm, forming a low-resistance gas rising channel.

[0089] The trap 400 operates under normal pressure, with the operating temperature controlled between 25°C and 30°C, and the operating liquid-to-gas ratio (L / G) maintained at a constant 5.0 L / Nm³. 3 .

[0090] After the process is started, the mixed absorbent (lean liquid) is transported into the tower. The mixed absorbent is sprayed through the slits of the liquid distributor 420 and efficiently adheres to the surface of the hydrophilic microporous mass transfer layer 130 of the resonant composite plate 100, forming a uniform and continuous thin liquid film under the pull of gravity.

[0091] To verify the strengthening effect of the present invention, the following two sets of comparative experiments were conducted:

[0092] (1) Static reference condition (sound field off):

[0093] Without the intelligent acoustic field control unit activated, the high viscosity of the mixed absorbent after absorbing CO2 results in a thick liquid film on the surface of the hydrophilic microporous mass transfer layer 130, leading to laminar flow. At this point, a high-concentration CO2 saturated layer rapidly forms at the gas-liquid interface, causing concentration polarization. Due to the lack of effective turbulence, fresh absorbent cannot be replenished to the interface in time, resulting in an extremely low mass transfer coefficient on the liquid side. Although the mixed absorbent has a very high saturated absorption capacity, the extremely slow mass transfer kinetics caused by its high viscosity limit the CO2 molecules to penetrate sufficiently into the deeper liquid phase under continuous contact experimental conditions with limited column height. The calculated overall CO2 removal rate is approximately 35%.

[0094] (2) Sound field synergistic enhancement condition (sound field on):

[0095] In the intelligent sound field control unit, the central processing unit 700 reads the real-time dynamic viscosity μ and temperature T fed back by the online monitoring module 600 at a sampling rate of 1 Hz. Based on the basic dynamic viscosity μ0(T) of the mixed absorbent at the real-time temperature T of the fresh lean solution, and setting the viscosity change threshold coefficient k to 0.25, the system calculates the dynamic viscosity threshold μ in real time. set The value is 50 mPa·s. The central processing unit 700 compares the real-time dynamic viscosity μ with the calculated dynamic viscosity threshold μ. set Real-time comparison is performed. In the initial stage of absorption, when the real-time dynamic viscosity μ is lower than the dynamic viscosity threshold μ... set At this time, the system enters energy-saving mode, controlling the power supply 300 to output low-power-density intermittent pulse drive signals, maintaining the sound power density at approximately 0.1 W / cm². 2 .

[0096] As the absorption process progresses, when the real-time dynamic viscosity μ reaches or exceeds the dynamic viscosity threshold μ... set At this time, the system automatically switches to enhancement mode. The power supply 300 outputs a high-power-density continuous drive signal, rapidly increasing the sound power density to 0.5-1.0 W / cm². 2 Meanwhile, the intelligent sound field control unit controls the power supply 300 to start the automatic frequency sweep function, which performs a rapid frequency sweep in the range of 20kHz to 50kHz. By detecting the impedance phase angle, it locks the optimal resonant frequency point under the current liquid film thickness and load, so that the system always works in a high-efficiency state.

[0097] In enhancement mode (with a sound power density of 0.5 W / cm²) 2 Taking the example of piezoelectric transducer array layer 110, the high-frequency ultrasonic waves generated penetrate vertically through the liquid film. Experimental measurements show that under the shear thinning effect of the acoustic field, the apparent viscosity of the mixed absorbent decreases by about 30% temporarily, causing the liquid film to spread more evenly and thinner on the microporous surface, and the effective gas-liquid contact area increases by about 40% compared with the absence of an acoustic field.

[0098] As the system continued to operate, the absorption load of the mixed solvent further increased, and the online monitoring module 600 detected that the real-time dynamic viscosity μ rose to over 60 mPa·s, significantly exceeding the current dynamic viscosity threshold μ. set The system then performs adaptive adjustment, reducing the sound power density from 0.5 W / cm². 2 Increased to 0.8 W / cm 2 The driving frequency is fine-tuned. Experiments show that the compensation mechanism based on dynamic thresholds can accurately overcome the mass transfer resistance caused by urethane accumulation.

[0099] Under the same gas-liquid ratio and temperature conditions, compared to traditional static packed towers or operating conditions without an active acoustic field, the CO2 concentration of the gas at the top outlet of this embodiment is stably reduced to approximately 2.8%, and the CO2 removal rate is increased from 35% to 81.3%, achieved using the acoustic field synergistic enhancement process described in this embodiment. Thanks to the vertical flat plate airflow channel design, the gas pressure drop is reduced by 60% compared to a packed tower with the same throughput. This demonstrates that, without changing the absorbent chemical formulation, this invention effectively overcomes the mass transfer resistance of high-viscosity solvents by introducing an active acoustic field and optimizing the flow channel, achieving capture performance with industrial application value.

[0100] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A planar membrane mass transfer internal based on sound field enhancement, characterized in that, The flat-plate membrane mass transfer internals include a plurality of vertically arranged resonant composite plates and a support assembly for supporting the resonant composite plates. A gas flow channel is formed between adjacent resonant composite plates, wherein: The resonant composite plate is a layered structure with double-sided mass transfer, which includes, from the inside out, a piezoelectric transducer array layer, an acoustic impedance matching layer, and a hydrophilic microporous mass transfer layer; the piezoelectric transducer array layer is electrically connected to the power supply and is used to generate high-frequency mechanical vibration, thereby forming a high-frequency sound field; The support assembly includes several limiting grooves located above and below the resonant composite plate, and a frame for fixing the limiting grooves; the resonant composite plate is floatingly installed in the limiting grooves, and its upper and lower ends form a clearance fit with the limiting grooves.

2. The planar membrane mass transfer internal based on sound field enhancement according to claim 1, characterized in that, The piezoelectric transducer array layer includes several piezoelectric vibration units and conductive wires. The piezoelectric vibration units are arranged in a matrix on a two-dimensional plane, and each piezoelectric vibration unit is electrically connected to the others through conductive wires. The piezoelectric vibration units are selected from one or more of PZT-5H type piezoelectric ceramic wafers, PZT-4 type piezoelectric ceramic wafers, PZT-8 type piezoelectric ceramic wafers, and lead-free piezoelectric ceramic materials.

3. The planar membrane mass transfer internal based on sound field enhancement according to claim 1, characterized in that, The acoustic impedance matching layer covers the outside of the piezoelectric transducer array layer, forming an insulating encapsulation structure; the acoustic impedance value of the acoustic impedance matching layer is between that of the piezoelectric transducer array layer and the absorbent in contact with the hydrophilic microporous mass transfer layer.

4. The planar membrane mass transfer internal based on sound field enhancement according to claim 1, characterized in that, The hydrophilic microporous mass transfer layer has a smooth, flat surface, a thickness of 50 μm to 100 μm, and an average pore size of 0.1 μm to 0.5 μm. The hydrophilic microporous mass transfer layer is a hydrophobic membrane or a hydrophilic membrane, the specific type of which is selected according to the wetting characteristics of the absorbent. The hydrophobic membrane is selected from one or more of polytetrafluoroethylene microporous membranes, polyvinylidene fluoride microporous membranes, and polyimide microporous membranes. The hydrophilic membrane is selected from one or more of plasma-modified polytetrafluoroethylene microporous membranes, plasma-modified polyvinylidene fluoride microporous membranes, plasma-modified polyimide microporous membranes, and hydrophilic porous ceramic membranes.

5. The planar membrane mass transfer internal based on sound field enhancement according to claim 2, characterized in that, The top of the resonant composite plate has an embedded acoustic energy driving interface; the conductive wires of the piezoelectric transducer array layer converge at the acoustic energy driving interface, and corrosion-resistant flexible leads are led out from the acoustic energy driving interface to connect to the power supply.

6. The planar membrane mass transfer internal based on sound field enhancement according to claim 1, characterized in that, The support assembly has a filter plate between the limiting grooves located below the resonant composite plate; the limiting grooves are provided with corrosion-resistant elastic damping components.

7. A collection tower employing the acoustic field-enhanced flat-plate membrane mass transfer internals as described in any one of claims 1-6, characterized in that, The trapping tower includes a tower body, inside which at least one layer of the flat sheet membrane mass transfer internals is arranged vertically; the frame of the support assembly of the flat sheet membrane mass transfer internals is fixedly connected to the inner wall of the tower body; the trapping tower is provided with a raw material inlet, a purified gas outlet, a lean liquid inlet, and a rich liquid outlet; the trapping tower is provided with a liquid distributor communicating with the lean liquid inlet at the upper part of the flat sheet membrane mass transfer internals, and the liquid outlet of the liquid distributor is located directly above the gas flow channel formed between adjacent resonant composite plates; The outer wall of the tower body is provided with airtight through-wall connection terminals at positions corresponding to each layer of the resonant composite plate; the piezoelectric transducer array layer of the plate membrane mass transfer internals is connected to the power supply via the airtight through-wall connection terminals.

8. A collection system employing the collection tower of claim 7, characterized in that, The capture system includes a capture tower, a regeneration unit, and an intelligent sound field control unit; The regeneration unit is connected to the rich liquid outlet and the lean liquid inlet of the collection tower via pipelines. The intelligent sound field control unit includes an online monitoring module, a central processing unit, and a power supply; The online monitoring module is installed on the pipeline at the outlet of the rich liquid and is used to detect the dynamic viscosity μ and temperature T of the rich liquid in real time, and transmit the viscosity signal and temperature signal to the central processing unit. The central processing unit integrates a multi-channel signal generator, a PID feedback control algorithm, and an absorbent property database, used to generate a dynamic viscosity threshold μ based on the absorbent type currently in operation and its real-time temperature T. set； The dynamic viscosity threshold μ set Determined by the following formula: m set =μ0(T) ×(1+k) Wherein, μ0(T) is the basic dynamic viscosity of the absorbent used in the collection system at temperature T for fresh lean liquid, and k is a preset viscosity change critical coefficient; the viscosity change critical coefficient k is a dimensionless empirical parameter, the value of which is determined by the rheological properties of the absorbent system and the acid gas loading. The central processing unit is also used to obtain the dynamic viscosity μ and the dynamic viscosity threshold μ from the online monitoring module. set The comparison is performed, and a drive adjustment command containing the target frequency f and the target voltage amplitude V is output to the power supply based on the comparison result; The power supply is electrically connected to the piezoelectric transducer array layer in the resonant composite plate, and is used to adjust the output frequency and output voltage amplitude according to the driving adjustment command, so as to adjust the vibration intensity and vibration frequency of the piezoelectric transducer array layer and realize dynamic closed-loop control of the sound field.

9. The collection system according to claim 8, characterized in that, The central processing unit of the intelligent sound field control unit executes the following control logic: The dynamic viscosity μ monitored by the online monitoring module is compared with the dynamic viscosity threshold μ. set Compare; When the dynamic viscosity μ is lower than the dynamic viscosity threshold μ set When the power supply outputs a corresponding drive signal, the piezoelectric transducer array layer enters the energy-saving mode. When the dynamic viscosity μ is higher than the dynamic viscosity threshold μ set At that time, the power supply is controlled to output a corresponding drive signal, causing the piezoelectric transducer array layer to enter the enhancement mode.

10. The collection system according to claim 9, characterized in that, In the energy-saving mode, the intelligent sound field control unit controls the power supply to output a low-power-density intermittent pulse drive signal; in the enhanced mode, the intelligent sound field control unit controls the power supply to output a high-power-density continuous drive signal, and controls the power supply to automatically sweep the frequency within a preset frequency range to lock the optimal resonant frequency.

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