Solution absorption type air purifier and purification method

Abstract

The invention discloses a solution absorption type air purifier and a purification method. A purification box communicates with an air inlet system, and a water outlet system and a self-cleaning system are arranged at the bottom of the purification box; the purification box body is filled with a functional solution; a filtering and absorbing system, a photoelectrocatalysis system and a purification air outlet system are arranged in the purification box body from bottom to top. Polluted air fed into the purification box body by the air inlet system is subjected to primary filtration by the filtration and absorption system and cut into tiny bubbles to be dissolved into a functional solution, the air is subjected to photoelectric secondary catalytic oxidation by the photoelectric catalysis system, and the purified air is discharged after being subjected to tertiary adsorption by the purification air outlet system; and the purified particle suspended solids are settled, stood through a water outlet system and discharged after being settled. A stainless steel wire net of the filtering and absorbing system is used for cutting air to generate tiny bubbles, particulate matters and VOCs are dissolved in a functional solution, photoelectrocatalytic oxidation and adsorption of an activated carbon fiber adsorption layer are carried out, fine particulate matters are removed, gas is efficiently purified, and the problem of blockage of a filtering device is solved.

Description

Technical Field

[0001] The present invention relates to the field of air purification treatment, and particularly to a solution absorption type air purifier and a purification method. Background Art

[0002] In recent years, air pollution has become a hot issue that people are concerned about. Indoor air pollutants include particulate pollutants, gaseous pollutants and microbial pollutants. Among them, gaseous pollutants are particularly difficult to control due to their wide sources and high removal difficulty, which has become a difficult point in indoor air pollution control. Using air purification equipment can effectively reduce indoor air pollution and improve the office and living environment.

[0003] Most of the existing air purification equipment uses a filtering device composed of multiple layers of fibers or porous materials to first filter and remove particulate pollutants in the air, and then purify gaseous pollutants and microbial pollutants through purification technologies such as adsorption, advanced oxidation and disinfection. However, the common problems of current air purifiers are incomplete purification of fine particle escape and easy blockage of the filtering device. The filtering device is easily covered by pollutants or blocked due to excessive accumulation of pollutants, which limits the efficiency and service life of the filtering device. It is necessary to regularly replace or clean the filtering device to maintain the best purification performance, which increases the use cost and maintenance time of the air purifier. A water absorption type organic volatile gas treatment device and treatment method disclosed in Chinese Patent Application No. 201811196483.1 purify VOCs gas through a water mist type gas absorption module and a photoelectrocatalytic module, but there are also problems such as blockage of the aerator and the filtering porous material, the need to replace the filter material, and inability to self-clean, which is not suitable for the purification of air particles. At the same time, using water as the photoelectrocatalysis lacks an electron transfer medium, and the efficiency of the advanced oxidation degradation function is low.

[0004] Currently, the technology of using membrane aeration - solution absorption to purify polluted gases has attracted the attention of scientists. This technology divides polluted gases into tiny bubbles through a polypyrrole membrane and dissolves them in a functional solution, playing a role in purifying the air.

[0005] However, the above technical solutions also have obvious deficiencies: the membrane is only used for aeration, and its conductive membrane does not have the function of electrochemically degrading organic pollutants, with low self-cleaning efficiency and long time consumption. The solution has poor versatility, limited application range, strong corrosiveness, and may cause environmental and health risks. The bubbles agglomerate during the upward floating process, and the bubble diameter becomes larger, which is not conducive to solution absorption.

[0006] The existing membrane matrix materials have poor hardness and strength, and the membrane coating materials have poor mechanical strength, are prone to cracking, have low wear resistance, and poor stability in high-humidity environments. They are prone to deformation under long-term membrane pressing and cavitation, and the coating is easy to fall off, resulting in the corrosion and fracture of the aeration membrane and the loss of function, making it difficult to meet the air purification requirements under large flow and high membrane pressure conditions. The problem of removing particulate matter dissolved in the solution has not been effectively solved.

[0007] Therefore, there is a need to provide a new type of air purifier with high efficiency in the purification process, capable of preventing blockage and having a self-cleaning function to solve the above problems. Summary of the Invention

[0008] To solve the above-mentioned defects in the prior art, the purpose of the present invention is to provide a solution absorption type air purifier and purification method, which combines a solution absorption system with a photo-electrocatalytic oxidation technology. Aeration is carried out by setting multiple layers of conductive microporous aeration membranes, and the redox property of the conductive microporous aeration membranes is adjusted by positive or negative potential pulses, so as to transfer particulate pollutants, gaseous organic pollutants and microbial pollutants in the air to the functional solution and synchronously realize catalytic oxidation; and keep the conductive microporous aeration membranes self-cleaning to prevent the accumulation and blockage of particulate matter, and then carry out advanced oxidation treatment on the organic pollutants and microbial pollutants in the functional solution through the photo-electrocatalytic oxidation technology to achieve the purpose of air purification.

[0009] The present invention is realized through the following technical solutions.

[0010] One aspect of the present invention provides a solution absorption type air purifier, which includes a purification box body, an air inlet system communicating with the purification box body, a water outlet system located at the bottom of the purification box body, and a self-cleaning system communicating with the purification box body;

[0011] The purification box body is filled with a functional solution; a filtration and absorption system, a photo-electrocatalytic system and a purified air outlet system are arranged in the purification box body from bottom to top;

[0012] It also includes a circuit control system electrically connected to the filtration and absorption system, the photo-electrocatalytic system and the air inlet system;

[0013] The polluted air sent into the purification box body by the air inlet system is first filtered by the filtration and absorption system to cut the air into tiny bubbles and dissolve them into the functional solution, and then the air is photo-electrically catalytically oxidized by the photo-electrocatalytic system. The purified air is discharged after being adsorbed three times by the purified air outlet system;

[0014] The settled particulate suspended matter after purification is discharged through the water outlet system after standing and sedimentation.

[0015] Preferably, the air inlet system includes an air inlet fan, an air inlet pipeline, and a gas check valve and an intake solenoid valve arranged on the air inlet pipeline.

[0016] Preferably, the filtration and absorption system includes a plurality of columnar aeration oxidation devices, and the columns of the plurality of columnar aeration oxidation devices are vertically placed on a horizontally arranged grid-shaped support frame; two layers of conductive microporous aeration membranes are horizontally installed in the columnar aeration oxidation device, and the two layers of conductive microporous aeration membranes are respectively connected to positive and negative electrodes to form a closed circuit; the bottoms of the columnar aeration oxidation devices are connected by pipelines.

[0017] The conductive microporous aeration membrane matrix thin plate is densely covered with uniform holes with a pore diameter of 10-1000 microns; the pore diameter of the upper conductive microporous aeration membrane is smaller than that of the lower conductive microporous aeration membrane.

[0018] Preferably, the matrix of the conductive microporous aeration membrane is at least one of platinum metal, titanium metal or stainless steel, and the thickness of the thin plate is 100-3000 microns;

[0019] The conductive microporous aeration membrane is provided with a coating, and the coating material is at least one of graphene, TiO 2 -IrRu, IrO 2 -Ta 2 O 5 .

[0020] Preferably, the photoelectrocatalytic system includes multiple groups of light sources, a photoelectrocatalytic cathode and a photoelectrocatalytic anode arranged vertically and alternately, and the light sources, the photoelectrocatalytic cathode and the photoelectrocatalytic anode are arranged on the support frame and the lower ends are immersed in the functional solution; the functional solution is a mixed solution of 0.03-0.08 mol / L lithium bis(fluorosulfonyl)imide and 0.2-0.5 mol / L 1-butyl-3-methylimidazolium tetrafluoroborate aqueous solution.

[0021] Preferably, a liquid level detector is installed on the inner wall of the purification box.

[0022] Preferably, the photoelectrocatalytic anode is at least one of TiO 2 -IrRu, Pt / TiO 2 , Pt / TiO 2 -ZnO and Fe / TiO 2 -ZnO composite oxide coating electrodes, and the anode conductive substrate can be selected from one or more of FTO, stainless steel and titanium metal.

[0023] The photoelectrocatalytic cathode can be selected from at least one of stainless steel, titanium metal and copper metal materials.

[0024] Preferably, the wavelength of the light source of the photoelectrocatalytic system is 254-500 nm, and the wavelength can be independently selected to include any value of 254 nm, 365 nm, 430 nm, 461 nm, 500 nm or the range value between the two.

[0025] Preferably, the purified air outlet system includes an activated carbon fiber adsorption layer, and the upper end of the activated carbon fiber adsorption layer is connected to the air outlet.

[0026] Preferably, the water outlet system is an inclined plate sedimentation tank with a bucket-shaped structure. Multiple layers of inclined plates are arranged at intervals inside the bucket-shaped structure. The pipeline air outlet is located above the bucket-shaped structure, and the bottom of the bucket-shaped structure is connected to the drain outlet through a sewage pipeline.

[0027] Preferably, the self-cleaning system includes a circulating water pump arranged outside the purification box body. The water inlet end of the circulating water pump is connected to a pipeline, and the water outlet end is connected to the lower side wall of the purification box body through a pipeline.

[0028] Another aspect of the present invention provides a method for purifying air using the solution absorption type air purifier described above, including:

[0029] Air purification process:

[0030] Start the air inlet system of the solution absorption type air purifier. Air enters the filtration and absorption system through the air inlet fan via a pipeline, enters from the bottom of the columnar aeration oxidation device inside the purification box body, and passes through two horizontally installed conductive microporous aeration membranes in sequence. The air is cut into tiny bubbles and enters the functional solution filled in the purification box body; the two conductive microporous aeration membranes are respectively connected to positive and negative electrodes, and a voltage is applied. The surface potential of the membrane is increased, which can relieve membrane fouling and remove membrane fouling online, and conduct primary oxidation purification on organic pollutants in the air.

[0031] Particulates, organic pollutants, and microorganisms in the tiny bubbles generated by the air enter the functional solution filled in the purification box body. The organic pollutants and microorganisms are subjected to primary oxidation by the photoelectrocatalytic system immersed in the functional solution.

[0032] A small amount of organic matter and microorganisms escape into the upper gas phase space with the tiny bubbles and are subjected to secondary advanced oxidation by the photoelectrocatalytic system in the gas phase space.

[0033] The purified air passes through the activated carbon fiber adsorption layer of the purified air outlet system and is discharged through the air outlet.

[0034] Precipitation and cleaning of the solution process:

[0035] Particulates in the functional solution sink through the grid-shaped support frame of the filtration and absorption system, precipitate in the inclined plate sedimentation tank of the water outlet system, reach the bottom of the inclined plate sedimentation tank, and are discharged through the sewage pipeline.

[0036] The functional solution is replenished to the high water level through the upper water replenishment port of the purification box body.

[0037] Automatic cleaning process:

[0038] When the conductive microporous aeration membrane is severely polluted after long-term use, the intake solenoid valve remains closed, the water inlet solenoid valve remains open, the circulation water pump remains started, a DC power supply is connected between the positive and negative electrodes of the two-layer conductive microporous aeration membrane, the voltage is controlled, the polarity of the two-layer conductive microporous aeration membrane is adjusted by changing the DC power supply, and the functional solution is pumped back to the purification box by the circulation water pump to achieve self-cleaning of the two-layer conductive microporous aeration membrane.

[0039] Due to the adoption of the above technical solutions, the present invention has the following beneficial effects:

[0040] 1. The present invention replaces the traditional mechanical filtration and adsorption device technology by using a solution filtration and absorption system. Through two layers of conductive microporous aeration membranes horizontally installed in multiple columnar aeration oxidation devices of the filtration and absorption system, the air bubbles are divided into micron-sized microbubbles, which are incorporated into a functional solution of lithium bis(fluorosulfonyl)imide (LiFSI) and 1-butyl-3-methylimidazolium tetrafluoroborate, specifically solving the problem of fine particulate matter purification that is difficult to solve by existing filtration-type air purifiers, and achieving the purpose of deep air purification.

[0041] 2. The present invention uses two layers of conductive microporous aeration membranes with high strength and good wear resistance to perform secondary division of microbubbles, effectively solving problems such as low membrane pressure resistance and wear resistance, poor stability in high-humidity environments, poor uniformity of microbubble distribution, large particle size of bubble agglomeration that is not conducive to solution absorption, and inability to meet the requirements of large-flow and high-pressure air purification.

[0042] 3. The present invention uses lithium bis(fluorosulfonyl)imide (LiFSI) and 1-butyl-3-methylimidazolium tetrafluoroborate as the functional solution to absorb air pollutants. The solution has strong conductivity and hydrophobic pollutant absorption performance, and the electron transfer efficiency of the conductive microporous aeration membrane and the photoelectrocatalytic system is high, specifically solving problems such as poor versatility of existing functional solutions, limited application range, strong corrosiveness, and possible environmental and health risks.

[0043] 4. By connecting a DC power supply to the two layers of conductive microporous aeration membranes serving as positive and negative electrodes, one layer of conductive microporous aeration membrane serving as the positive electrode exhibits an oxidized state (hydrophilic), and one layer of conductive microporous aeration membrane serving as the negative electrode exhibits a reduced state (hydrophobic). By changing the DC power supply, the polarity and redox state of the two layers of conductive microporous aeration membranes can be adjusted, and the electrochemical oxidation-reduction and gas evolution synergistic effects generated by the conductive membrane are used to clean the membrane surface; when a voltage is applied to the two layers of conductive microporous aeration membranes during aeration, membrane fouling can be reduced.

[0044] 5. The light source, the photoelectrocatalytic cathode, and the photoelectrocatalytic anode of the photoelectrocatalytic system of the present invention are immersed in the functional solution at the lower end and placed in the gas phase space at the upper end. The photoelectrocatalytic system immersed in the functional solution performs advanced oxidation decomposition of the VOCs dissolved in the functional solution into CO 2 and H2 O. For the VOCs that may escape from the solution, the photocatalytic oxidation system placed in the gas phase space can perform secondary advanced oxidation purification. The purified air is discharged through the air outlet after passing through the activated carbon fiber adsorption layer, ensuring the quality of the purified air.

[0045] 6. A lamella sedimentation tank is provided at the bottom of the purification box body of the present invention. The lamella sedimentation tank has a hopper-shaped structure, and multiple layers of inclined plates are arranged in the hopper-shaped structure to form a static area in the hopper-shaped structure, avoiding the disturbance of the water body, facilitating the sedimentation of particulate suspensions in the functional solution to the bottom of the lamella sedimentation tank, and ensuring the cleanliness of the functional solution. Description of the Drawings

[0046] The drawings described herein are used to provide a further understanding of the present invention, form a part of this application, and do not constitute an improper limitation to the present invention. In the drawings:

[0047] Figure 1 is an overall structure diagram of a novel solution absorption type air purifier related to the embodiment of the present invention;

[0048] Figure 2 is a top view of a filtration and absorption system of a novel solution absorption type air purifier related to the embodiment of the present invention;

[0049] Figure 3 is a three-dimensional structure diagram of a columnar aeration oxidation device of a novel solution absorption type air purifier related to the embodiment of the present invention;

[0050] Figure 4 is the durability analysis of the conductive microporous aeration membrane of the present invention.

[0051] Description of the reference numerals: 1, inlet air fan; 11, gas check valve; 12, inlet air solenoid valve; 13, pipeline; 2, circulation water pump; 21, inlet water solenoid valve; 3, purification box body; 41, grid-shaped support frame; 42, columnar aeration oxidation device; 43, conductive microporous aeration membrane; 51, light source; 52, photocatalytic cathode; 53, photocatalytic anode; 54, support frame; 6, water replenishment port; 7, activated carbon fiber adsorption layer; 8, air outlet; 9, circuit control system; 91, liquid level detector; 101, lamella sedimentation tank; 102, multiple layers of inclined plates; 103, drain valve; 104, sewage pipeline. Detailed Embodiments

[0052] The present invention will be described in detail below in conjunction with the drawings and specific embodiments. Here, the illustrative embodiments and descriptions of the present invention are used to explain the present invention, but do not limit the present invention.

[0053] Reference Figure 1As shown in the figure, the solution absorption type air purifier provided by the embodiment of the present invention includes an air inlet system, a purification box body 3, a filtration and absorption system, a photo-electrocatalytic system, a purified air outlet system, a water outlet system, and a circuit control system 9; a filtration and absorption system, a photo-electrocatalytic system, and a purified air outlet system are arranged in the purification box body 3 from bottom to top, and the purification box body 3 is filled with a functional solution; the air inlet system is communicated with the purification box body 3 to the filtration and absorption system, and the circuit control system 9 is respectively connected to the air inlet system, the filtration and absorption system, and the photo-electrocatalytic system; it also includes a self-cleaning system communicated with the lower cavity of the purification box body 3 and a pipeline 13, and a water outlet system is arranged at the bottom of the purification box body 3.

[0054] The air inlet system includes an air inlet fan 1, a pipeline 13, a gas check valve 11 and an intake electromagnetic valve 12 arranged on the pipeline 13, and the gas check valve 11 can prevent liquid from flowing back into the fan through the pipeline.

[0055] As Figure 2 , Figure 3 shown, the filtration and absorption system includes a plurality of columnar solution absorption devices 42. The columns of the plurality of columnar solution absorption devices 42 are vertically arranged on a horizontally arranged grid-shaped support frame 41. The grid-shaped support frame is a fine skeleton structure, and a plurality of cavities are formed between the fine skeletons to facilitate the flow of the functional solution. When the machine is stopped, the particulate matter in the functional solution above the grid-shaped support frame can pass through the grid-shaped support frame by free sedimentation and precipitate to the bottom of the sedimentation tank to keep the solution clean.

[0056] Two layers of conductive microporous aeration membranes 43 are horizontally installed in the columnar aeration oxidation device 42. Uniform holes are densely distributed on the matrix thin plate of the conductive microporous aeration membrane; it is prepared by punching methods such as laser punching, micro-EDM, chemical / electrochemical etching, photolithography + etching, electron beam, and micro-drill machining. The pore diameter of the upper conductive microporous aeration membrane 43 is smaller than that of the lower conductive microporous aeration membrane 43; the two layers of conductive microporous aeration membranes 43 are respectively connected to the positive and negative electrodes to form a closed circuit. The bottom of each columnar solution absorption device 42 is communicated with the pipeline 13.

[0057] In one embodiment, the distance between the two layers of conductive microporous aeration membranes 43 is 1 - 4 cm, the pore diameter of the conductive microporous aeration membrane 43 is 10 - 1000 μm, and the preferred pore diameter is 10 - 500 μm. The voltage is 0.4 - 1.2 V, and the current density is 0.1 - 10 mA / cm 2 .

[0058] The matrix of the conductive microporous aeration membrane is platinum metal, titanium metal or stainless steel, and the thickness of the thin plate is 100 - 3000 μm. The conductive microporous aeration membrane is provided with a coating, and the coating material is graphene, TiO 2 -IrRu or IrO 2 -Ta 2 O 5The coating preparation method involves first pre - treating the substrate thin plate by cleaning and polishing, and then preparing it by methods such as coating, spraying, electrochemistry, chemical polymerization, magnetron sputtering, etc.

[0059] The lower - layer conductive microporous aeration membrane 43 makes a primary division of the air. Particles in the gas can all pass through the lower - layer conductive microporous aeration membrane 43. When passing through the upper - layer conductive microporous aeration membrane 43, the bubbles are secondarily divided. Particles in the range larger than 10 - 20 μm will be retained on the lower surface of the upper - layer conductive microporous aeration membrane 43, and particles in the range smaller than 10 - 20 μm will pass through the upper - layer conductive microporous aeration membrane 43. The generated micro - bubbles enter the functional solution filled in the purification box 3 and slowly float upward. Through the secondary bubble division by the upper and lower layers of conductive microporous aeration membranes 43, the adverse effect of bubble coagulation and enlargement on the dissolution of micro - bubble pollutants in the solution is reduced.

[0060] Among them, the functional solution is a mixed solution of 0.03 - 0.08 mol / L lithium bis(fluorosulfonyl)imide and 0.2 - 0.5 mol / L 1 - butyl - 3 - methylimidazolium tetrafluoroborate aqueous solution; preferably, it is a mixed solution of 0.05 mol / L lithium bis(fluorosulfonyl)imide and 0.3 mol / L 1 - butyl - 3 - methylimidazolium tetrafluoroborate aqueous solution.

[0061] This functional solution can effectively improve the electrolyte conductivity characteristics, improve the electron transfer efficiency of the photoelectrocatalytic system, reduce concentration polarization, lower the electric potential energy of the conductive microporous aeration membrane 43, reduce the power consumption, improve the advanced oxidation ability of generating hydroxyl radicals (·OH) and superoxide radicals (·O2 - ) and the gas evolution synergistic effect in the electrochemical oxidation - reduction reaction of the conductive microporous aeration membrane 43, play a cleaning role on the membrane surface, slow down the membrane pollution process, and enhance the efficiency of advanced oxidation for degrading organic pollutants.

[0062] The functional solution of lithium bis(fluorosulfonyl)imide (LiFSI) and 1 - butyl - 3 - methylimidazolium tetrafluoroborate aqueous solution can improve the solubility of hydrophobic and poorly soluble organic pollutants, reduce or avoid the escape of organic pollutants from the liquid phase to the gas - phase space, and improve the ability of the solution to capture pollutants in dissolved micro - bubbles. The photoelectrocatalytic system in both the liquid phase and the gas phase can degrade organic pollutants through advanced oxidation.

[0063] As Figure 1 shown, the photoelectrocatalytic system is composed of multiple groups of light sources 51, a photoelectrocatalytic cathode 52, and a photoelectrocatalytic anode 53. The light sources 51, the photoelectrocatalytic cathode 52, and the photoelectrocatalytic anode 53 are arranged vertically and alternately, mounted on the support frame 54, with the lower end immersed in the functional solution and the upper end placed in the gas - phase space.

[0064] A liquid level detector 91 is installed on the inner wall of the purification box body 3. The photo-electrocatalysis system is arranged vertically. The upper liquid level detector is located at the position of 3 / 4 of the height above the bottom of the photo-electrocatalysis system (the bottom of the light source 51, the photo-electrocatalysis cathode 52 and the photo-electrocatalysis anode 53), and the lower liquid level detector is located at the position of 1 / 2 of the height above the bottom of the photo-electrocatalysis system, which can ensure that the photo-electrocatalysis system can play a role in both the functional solution and the gas phase space.

[0065] The wavelength of the light source 51 of the photo-electrocatalysis system is 254 - 500 nm, and the independently selectable wavelengths include any value among 254 nm, 365 nm, 430 nm, 461 nm, 500 nm or the range values between the two. The photo-electrocatalysis anode 53 is TiO 2 -IrRu, Pt / TiO 2 、Pt / TiO 2 -ZnO or Fe / TiO 2 -ZnO and other composite oxide coating electrodes. The anode conductive substrate can be selected from FTO, stainless steel or titanium metal. The photo-electrocatalysis cathode 52 can be selected from stainless steel, titanium metal or copper metal. Multiple ultraviolet light sources 51 are arranged around the photo-electrocatalysis anode 53.

[0066] In this embodiment, a purification box body with a diameter of 80 - 90 cm is selected, and the distance range between the photo-electrocatalysis anode 53 and each of the surrounding ultraviolet light sources 51 is preferably 5 - 20 cm.

[0067] Compared with the traditional photo-electrocatalysis anode, TiO 2 -IrRu, Pt / TiO 2 、Pt / TiO 2 -ZnO, Fe / TiO 2 -ZnO and other composite oxide coating electrodes have the advantages of stable physical and chemical properties, strong oxidation ability, safety and harmlessness.

[0068] Multiple groups of vertically arranged light sources 51, photo-electrocatalysis cathodes 52 and photo-electrocatalysis anodes 53 arranged in a staggered manner ensure that the light source 51 surrounding the photo-electrocatalysis electrode can well irradiate the surface of the photo-electrocatalysis anode 53. When the photo-electrocatalysis anode 53 is irradiated by light, excited state electron transition occurs, generating photo-generated electrons and holes on the electrode surface. At the same time, the holes react with water to generate hydroxyl radicals ·OH, and the electrons reduce O 2 to generate superoxide radicals ·O 2 - and H 2 O 2 and other reactive oxygen species. Organic pollutants can be directly oxidized by the holes or by the generated ·OH, ·O 2 - and H 2 O 2Degradation, the advanced oxidation ability of hydroxyl radicals (·OH) and superoxide radicals (·O 2 - ) can effectively kill microorganisms.

[0069] Particulates, organic pollutants, and microorganisms in the microbubbles generated by the air enter the functional solution filled in the purification box body 3. The organic pollutants and microorganisms are subjected to primary oxidation by the high-energy holes, hydroxyl radicals (·OH), and superoxide radicals (·O2-) of the photocatalytic system immersed in the functional solution. A small amount of organic matter and microorganisms escape into the upper gas phase space with the microbubbles and are subjected to advanced oxidation again by the photocatalytic system in the gas phase space, effectively purifying the organic pollutants and microorganisms in the air.

[0070] As Figure 1 shown, a purification air outlet system is provided at the top of the photocatalytic system, including an activated carbon fiber adsorption layer 7, and the upper end of the activated carbon fiber adsorption layer 7 is connected to the air outlet 8.

[0071] As Figure 1 shown, the self-cleaning system includes a circulating water pump 2 provided outside the evolution box body 3. The water inlet end of the circulating water pump 2 is connected to the pipeline 13, and the water outlet end is connected to the lower side wall of the purification box body 3 through a pipeline, and a water inlet solenoid valve 21 is provided on the water inlet pipeline.

[0072] In this embodiment, the circuit control system 9 controls the filtration and absorption system, the photocatalytic system, etc., mainly including the automatic control and operation of the power supply, current intensity, signal display, air flow, air particulate concentration, VOCs concentration, formaldehyde concentration, air temperature, air humidity, liquid level, inlet air fan, and valves, etc.

[0073] In order to better target the water outlet systems with different structures and better control the water outlet purification effect, thereby improving adaptability. The water outlet system located at the bottom of the purification box body 3 of the present invention is set as an inclined plate sedimentation tank 101. The inclined plate sedimentation tank 101 is of a hopper-shaped structure, and multiple inclined plates 102 are arranged in the hopper-shaped structure. Taking the purification box body with a diameter of 80-90 cm as an example, the inclined plate spacing is preferably 1-3 cm. The air outlet of the pipeline 13 is located above the hopper-shaped structure, and the bottom of the hopper-shaped structure is connected to the drain port through a sewage pipeline 104, and a drain valve 103 is installed at the connection.

[0074] Furthermore, the embodiment of the present invention provides an air purification method based on a solution absorption type air purifier, including the following steps:

[0075] a. Air purification process:

[0076] When the indoor space needs to purify the air, start the air inlet system of the solution absorption type air purifier, open the gas check valve 11 and the intake solenoid valve 12, and close the water inlet solenoid valve 21. The gas check valve 11 and the intake solenoid valve 12 remain open, and the water inlet solenoid valve 21 remains closed. Air enters the filtration and absorption system through the intake fan 1 via a pipeline. The gas enters from the bottom of the columnar solution absorption device 42 in the purification box body 3 and is filtered successively through two horizontally installed conductive microporous aeration membranes 43.

[0077] The air generates tiny bubbles in the size range of 50 - 500 μm. The tiny bubbles slowly rise in the functional solution filled in the purification box body 3. During the rising process of the tiny bubbles, particulate matter, organic pollutants, and microorganisms will be captured by the gas-liquid interface and enter the functional solution. The organic pollutants and microorganisms captured and entering the functional solution are subjected to advanced oxidation by the high-energy holes, hydroxyl radicals (·OH), and superoxide radicals (·O2-) generated by the photocatalytic cathode 51 and the photocatalytic anode 52 of the photocatalytic system immersed in the functional solution, which can oxidize the organic pollutants into CO 2 and H 2 O, and the microorganisms are inactivated.

[0078] A small amount of unoxidized organic matter and un-inactivated microorganisms escape from the functional solution into the upper gas phase space with the tiny bubbles and are subjected to re-advanced oxidation by the high-energy holes, hydroxyl radicals (·OH), and superoxide radicals (·O2-) generated by the photocatalytic cathode 51 and the photocatalytic anode 52 in the gas phase space, which can oxidize the organic pollutants into CO 2 and H 2 O, and the microorganisms are completely inactivated.

[0079] The purified air passes through the activated carbon fiber adsorption layer 7 of the purified air outlet system and is discharged through the air outlet 8.

[0080] In the air at the purified air outlet, the concentration of PM10 particulate matter is less than 5 ppm, the concentration of PM2.5 particulate matter is less than 3 ppm, the concentration of PM0.3 particulate matter is less than 0.1 ppm, the concentration of VOCs is less than 0.06 mg / m 3 , and the total number of bacteria is less than 63 cfu / m 3 . During the process of the solution absorption type air purifier purifying the air, when shutting down, the gas check valve remains closed to prevent the functional solution from flowing back into the fan 1.

[0081] b. Process of precipitating the cleaning solution:

[0082] The grid-shaped support frame 41 of the filtration and absorption system horizontally arranged at the lower part of the purification box body 3 is of a fine skeleton structure, and multiple cavities are formed between the fine skeletons. Larger particulate matters in the functional solution will sink through the cavities between the fine skeletons by free sedimentation, and then quickly sink to the bottom of the inclined plate sedimentation tank 101 of the water outlet system through the sedimentation effect of the inclined plate sedimentation tank 101, keeping the functional solution clean. After shutdown, the functional solution remains static, and the remaining fine particulate matters in the functional solution will still sink to the bottom of the inclined plate sedimentation tank 101 by free sedimentation, ensuring the cleanliness of the functional solution. The deposited particulate matters are regularly discharged through the sewage pipe at the bottom of the inclined plate sedimentation tank.

[0083] After long-term use, sludge will accumulate at the bottom of the inclined plate sedimentation tank. Open the drain valve 103, and the sludge is discharged through the sewage pipe 104 at the bottom of the inclined plate sedimentation tank. After the sludge discharge is completed, close the drain valve.

[0084] c. Automatic cleaning process:

[0085] When the two-layer conductive microporous aeration membranes 43 installed in the columnar solution absorption device 42 of the filtration and absorption system are blocked and the inlet air flow rate becomes small, self-cleaning needs to be started. When starting self-cleaning, close the intake solenoid valve 12, open the water inlet solenoid valve 21, the intake solenoid valve 12 remains closed, the water inlet solenoid valve 21 remains open, and the circulation water pump remains started; the positive and negative electrodes of the two-layer conductive microporous aeration membranes 43 are connected to a DC power supply, with a voltage of 0.4 - 1.2V and a current density of 0.1 - 10 mA / cm 2 , one layer of conductive microporous aeration membrane 43 as the positive electrode shows an oxidized state (hydrophilic), and one layer of conductive microporous aeration membrane 43 as the negative electrode shows a reduced state (hydrophobic). By changing the polarity of the two-layer conductive microporous aeration membranes 43 1 - 3 times, each time for 1 - 3 minutes, the particulate matters accumulated on the two-layer conductive microporous aeration membranes 43 will automatically fall off into the functional solution. At the same time, the circulation water pump 2 makes the functional solution pass through the two-layer conductive microporous aeration membranes 43 and is pumped into the circulation water pump 2 through the pipeline, and the functional solution is pumped back into the purification box body 3 through the pipeline connecting the water outlet end of the circulation water pump 2 and the lower side wall of the purification box body 3, realizing the self-cleaning of the two-layer conductive microporous aeration membranes 43. The self-cleaning time is set to 3 - 10 minutes, and the automatic cleaning of the two-layer conductive microporous aeration membranes 43 can be realized.

[0086] During automatic cleaning, the circulation water pump makes the functional solution flow reversely through the two-layer conductive microporous aeration membranes and is pumped into the circulation water pump through the pipeline, and the functional solution is pumped back into the purification box body through the pipeline connecting the water outlet end of the circulation water pump and the lower side wall of the purification box body. Through the scouring effect, the automatic cleaning of the two-layer conductive microporous aeration membranes is efficiently completed, specifically solving the problems of low self-cleaning efficiency and long time consumption of membrane pollution.

[0087] During the air purification or when the air purifier is not in use, the liquid level detector 91 installed on the inner wall of the purification box can automatically detect the liquid level of the functional solution in the box. The circuit control system 101 displays the liquid level height, reminding to supplement the functional solution through the water replenishment port 6 on the upper side wall of the purification box to ensure that the amount of the functional solution meets the purification requirements.

[0088] The following provides different embodiments to further illustrate the effects of the present invention.

[0089] Embodiment 1

[0090] When the concentration of particulate matter (PM10) in the air is 800 ppm, the concentration of VOCs is 8 mg / m 3 , and the air intake volume is 300 m 3 / h, using aqueous solutions of LiClO at 0.1 mol / L, Na 4 SO 2 at 0.05 ml / L, FeSO 4 at 0.3 mmol / L, aqueous solution of lithium bis(fluorosulfonyl)imide (LiFSI) at 0.05 mol / L, aqueous solution of lithium bis(fluorosulfonyl)imide (LiFSI) at 0.05 mol / L and 1-butyl-3-methylimidazolium tetrafluoroborate at 0.3 mol / L as the functional solutions of the device of the present invention, the influence of different functional solutions on the purification effect was measured. As shown in Table 1, the removal rates of particulate matter and VOCs by the aqueous solution of lithium bis(fluorosulfonyl)imide (LiFSI) at 0.05 mol / L and 1-butyl-3-methylimidazolium tetrafluoroborate at 0.3 mol / L are higher than those of other functional solutions. 4

[0091] Table 1 Purification effects of different functional solutions

[0092]

[0093] Embodiment 2

[0094] When the concentration of particulate matter PM10 in the air is 800 ppm, the concentration of PM2.5 is 700 ppm, the concentration of PM0.3 is 200 ppm, the concentration of VOCs is 8 mg / m 3 , the total number of bacteria is 9500 CFU / cm 2 , and the functional solution is an aqueous solution of lithium bis(fluorosulfonyl)imide (LiFSI) at 0.05 mol / L and 1-butyl-3-methylimidazolium tetrafluoroborate at 0.3 mol / L, at 300 m 3 / h, 500 m 3 / h, 1000 m 3 ​ / h is the air intake of the device of the present invention. The influence of different air intakes on the purification effect is measured, as shown in Table 2. The removal effects of particulate matters PM10, PM2.5, PM0.3 and VOCs all meet the indoor air purification requirements, and the total number of bacteria in the purified outlet air all meets the hygienic standard of 4000 cfu / m for the total number of bacteria in indoor air 3 。

[0095] Table 2 Purification effects of different air intakes

[0096]

[0097] Example 3

[0098] At a particulate matter (PM10) concentration of 1000 ppm and a VOCs concentration of 8 mg / m 3 , with an initial air intake of 500 m 3 / h, under the condition that the functional solution of the device of the present invention is an aqueous solution of lithium bis(fluorosulfonyl)imide (LiFSI) at 0.05 mol / L and 1-butyl-3-methylimidazolium tetrafluoroborate at 0.3 mol / L, the device of the present invention is continuously operated for 100 h, and the change in the air output of the conductive microporous aeration membrane under the conditions of applying voltage and not applying voltage is measured. As shown in the figure, under the condition of continuous operation for 100 h at a high particulate matter concentration, the air output of the conductive microporous aeration membrane under the condition of applying voltage drops to 87%, and the air output under the condition of not applying voltage drops to 60.2%. It can be seen that applying voltage can improve the anti-pollution ability of the conductive microporous aeration membrane

[0099] From the above tests and examples, it can be seen that the functional solution of the aqueous solution of lithium bis(fluorosulfonyl)imide (LiFSI) at 0.05 mol / L and 1-butyl-3-methylimidazolium tetrafluoroborate at 0.3 mol / L built in the device of the present invention has a better purification effect on particulate matters and VOCs than other functional solutions; the device of the present invention can meet the purification requirements for the removal of PM10, PM2.5, PM0.3, VOCs and the total number of bacteria under different air intakes and different concentration conditions, and the outlet air quality is guaranteed; from Figure 4 the analysis of the durability of the conductive microporous aeration membrane, it can be seen that when purifying air, applying voltage to the conductive microporous aeration membrane compared with not applying voltage can improve the self-cleaning and anti-blocking ability of the membrane, can delay the blocking process, reduce the self-cleaning frequency after blocking, and save energy consumption

[0100] The method of the present invention solves the problem of purifying fine particulate matters that is difficult to solve by existing filter-type air purifiers, guarantees the purification air quality, and achieves the purpose of deep air purification

[0101] The present invention is not limited to the above embodiments. Based on the technical solutions disclosed in the present invention, those skilled in the art can make some substitutions and deformations to some of the technical features without creative labor according to the disclosed technical content, and these substitutions and deformations are all within the protection scope of the present invention.

Claims

1. A solution absorption air purifier, characterized in that , including a purification box, an air inlet system connected to the purification box, a water outlet system located at the bottom of the purification box, and a self-cleaning system connected to the purification box; The purification box is filled with a functional solution; a filtering and absorbing system, a photoelectric catalytic system and a purified air outlet system are arranged from bottom to top in the purification box; It also includes a circuit control system electrically connecting the filtering and absorbing system, the photoelectric catalytic system and the air intake system; The polluted air sent into the purification box by the air intake system is filtered and cut into tiny bubbles by the first-level filtration and absorption system and dissolved into the functional solution. The air is oxidized by the second-level photoelectric catalytic system, and the purified air is discharged after being adsorbed by the third-level purification air outlet system. The purified suspended particulate matter settles and is discharged through the water outlet system after being allowed to stand and settle.

2. A solution absorption air purifier according to claim 1, characterized in that: The air intake system comprises an air intake fan, an air intake pipeline, and a gas check valve and an air intake solenoid valve arranged on the air intake pipeline.

3. A solution absorption air purifier according to claim 1, characterized in that: The filtration and absorption system comprises a plurality of columnar aeration and oxidation devices, wherein the columns of the plurality of columnar aeration and oxidation devices are vertically placed on a horizontally arranged grid-shaped support frame; two layers of conductive microporous aeration membranes are horizontally installed in the columnar aeration and oxidation devices, and the two layers of conductive microporous aeration membranes are respectively connected to positive and negative electrodes to form a closed circuit; The bottom connecting pipes of each columnar aeration and oxidation device; The conductive microporous aeration membrane substrate sheet is densely and evenly distributed with holes; the pore size of the upper conductive microporous aeration membrane is smaller than the pore size of the lower conductive microporous aeration membrane.

4. A solution absorption air purifier according to claim 3, characterized in that: The substrate of the conductive microporous aeration membrane is at least one of metal platinum, metal titanium or stainless steel; The conductive microporous aeration membrane is provided with a coating, and the coating material is at least one of graphene, TiO2-IrRu, and IrO2-Ta2O5.

5. A solution absorption air purifier according to claim 1, characterized in that: The photoelectrocatalytic system comprises a plurality of light sources, photoelectrocatalytic cathodes and photoelectrocatalytic anodes arranged in a staggered vertical manner, wherein the light sources, photoelectrocatalytic cathodes and photoelectrocatalytic anodes are placed on a support frame, and the lower ends are immersed in a functional solution; the functional solution is a mixture of 0.03-0.08 mol / L lithium bis(fluorosulfonyl)imide and 0.2-0.5 mol / L 1-butyl-3-methylimidazole tetrafluoroborate aqueous solution; A liquid level detector is installed on the inner wall of the purification box.

6. A solution absorption air purifier according to claim 5, characterized in that: The photoelectrocatalytic anode is at least one of TiO2-IrRu, Pt / TiO2, Pt / TiO2-ZnO and Fe / TiO2-ZnO composite oxide coating electrodes; The photoelectrocatalytic anode conductive substrate is selected from one or more of FTO, stainless steel and titanium metal; The photoelectrocatalytic cathode conductive substrate is selected from at least one of stainless steel, metal titanium and metal copper; The wavelength of the light source of the photoelectrocatalytic system is 254-500nm, and the wavelength can be independently selected to include any value of 254nm, 365nm, 430nm, 461nm, 500nm or a range of values ​​therebetween.

7. A solution absorption air purifier according to claim 1, characterized in that: The air purification system comprises an activated carbon fiber adsorption layer, and the upper end of the activated carbon fiber adsorption layer is connected to the air outlet.

8. A solution absorption air purifier according to claim 1, characterized in that: The water outlet system is a bucket-shaped inclined plate sedimentation tank, in which multiple layers of spaced inclined plates are arranged, the pipe air outlet is located above the bucket-shaped structure, and the bottom of the bucket-shaped structure is connected to the drain outlet through a sewage pipe.

9. A solution absorption air purifier according to claim 1, characterized in that: The self-cleaning system comprises a circulating water pump arranged outside the purification box, wherein a water inlet end of the circulating water pump is connected to a pipeline, and a water outlet end of the circulating water pump is connected to a lower side wall of the purification box through a pipeline.

10. A method for air purification using the solution absorption air purifier according to any one of claims 1 to 9, characterized in that: include: Air purification process: Start the air intake system of the solution absorption air purifier. The air enters the filtration absorption system through the air intake fan and the pipeline, and enters from the bottom of the columnar aeration oxidation device in the purification box. It passes through two layers of horizontally installed conductive microporous aeration membranes in turn. The air is cut into tiny bubbles and enters the functional solution filled in the purification box. Two layers of conductive microporous aeration membranes are connected to positive and negative electrodes respectively, and voltage is applied to remove membrane pollution online, and primary oxidation purification of organic pollutants in the air is performed; The particles, organic pollutants and microorganisms in the tiny bubbles generated by the air enter the functional solution filled in the purification box. The organic pollutants and microorganisms are first oxidized by the photoelectric catalytic system immersed in the functional solution. A small amount of organic matter and microorganisms escape into the upper gas phase space along with tiny bubbles and are further oxidized by the photoelectrocatalytic system in the gas phase space; The purified air passes through the activated carbon fiber adsorption layer of the purification air outlet system and is discharged through the air outlet; Precipitation cleaning solution process: The particles in the functional solution sink through the grid-like support frame of the filtration and absorption system, settle through the inclined plate sedimentation tank of the effluent system, reach the bottom of the inclined plate sedimentation tank, and are discharged through the sewage pipe; Replenish the functional solution to the high water level through the upper water filling port of the purification box; Automatic cleaning process: The air inlet solenoid valve remains closed, the water inlet solenoid valve remains open, the circulating water pump remains started, a DC power supply is connected between the positive and negative electrodes of the two layers of conductive microporous aeration membrane, the voltage is controlled, the polarity of the two layers of conductive microporous aeration membrane is adjusted by changing the DC power supply, and the functional solution is pumped back to the purification box through the circulating water pump to achieve self-cleaning of the two layers of conductive microporous aeration membrane.

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