CN104043320A

CN104043320A - Method for treatment of indoor air pollution by combination of photocatalytic plasma and ultrasonic

Info

Publication number: CN104043320A
Application number: CN201410194933.9A
Authority: CN
Inventors: 郑巍; 肖玲; 李昌国
Original assignee: CUI QIAOFU
Current assignee: CUI QIAOFU
Priority date: 2014-05-11
Filing date: 2014-05-11
Publication date: 2014-09-17
Anticipated expiration: 2034-05-11
Also published as: CN104043320B

Abstract

The invention discloses a method for treatment of indoor air pollution by combination of photocatalytic plasma and ultrasonic. The method includes the following steps: 1, a plasma discharge reactor is used to produce plasma free radicals, a strong electric field and ultraviolet light; 2, PM2.5 is absorbed through the strong electric; 3, the plasma free radicals are harmlessly treated by reaction of the plasma free radicals and VOCs (volatile organic chemcials) in the air; 4, incompletely reacted VOCs is further reacted in the presence of a TiO2 photocatalyst; 5, by-products NOx and O3 produced by the reaction are decomposed by a safe catalyst; 6, water or non-toxic organic absorbent and tail gas are mixed fully by an ultrasonic reactor, and fully react in a filling area, and remaining particles and VOCs are left in the organic absorbent; and 7, a tourmaline loaded nano titanium dioxide filler is used in the filling area. The method has the advantages of low energy consumption, small occupation of land, low noise, wide application range, and safe and reliable operation.

Description

A kind of photocatalysis plasma body is in conjunction with air-polluting method in ultrasonic wave process chamber

Technical field

The present invention relates to a kind of nano-photo catalytic corona plasma and process the method for indoor air pollutants in conjunction with ultrasonic wave organic matter absorption techniques, belong to atmosphere and administer technical field.

Background technology

Along with the air pollution day by day increasing the weight of, the degree that haze occurs is more and more higher, and frequency is more and more faster, and the duration is more and more longer, and PM2.5, as the important indicator of haze, directly affects people's living safety and quality.PM2.5 refers to that the particle of diameter≤2.5 in atmosphere micron is also referred to as entering lung particle.It has a significant impact air quality and visibility etc.PM2.5 because particle diameter is little, specific area greatly, is easily adhered to various hazardous contaminants, can directly enter in human body alveolar, therefore health is produced to serious threat.Because PM2.5 particle diameter is little, be difficult to fall from sedimentation or by rain drop erosion, therefore in air, be difficult to be removed.

Volatile organic matter VOCs is equally also one of major reason of haze generation, and airborne VOCs produces reaction and forms secondary pollution generation photochemical fog under the irradiation of sunshine, has strong impulse, toxicity, carcinogenicity.

Present stage only has 2 kinds in the indoor method that can effectively process PM2.5, and one is to use HEPA to filter; Another kind is to utilize anion to make PM2.5 particle form heavy ion sedimentation.But these two kinds of methods respectively have drawback.

1, use HEPA to filter, need the frequent HEPA of replacing, therefore cost of use costliness, HEPA changes and can cause not in time filter opening to stop up, and the HEPA simultaneously polluting can grow a large amount of microorganisms, becomes new pollution sources.

2, use anion to remove PM2.5, PM2.5 particle does not eliminate from environment, but is adsorbed in a large number indoor body surface, causes house dust to increase, and easily causes the other diseases such as allergy, asthma.

The VOCs treatment technology that present stage can be used in indoor environment only has charcoal absorption and photocatalysis technology, when long-time use, adsorption effect of activated carbon in water is poor, photocatalysis technology is because catalyst mainly activates and produces free electron and electron hole by ultraviolet light, and therefore degradation efficiency is very low.

Summary of the invention

The object of the invention is to propose a kind of air pollution treatment technology that is applicable to indoor environment.By using DC high voltage electric field that PM2.5 particle is collected on electrode, use the free radical of high pressure streamer discharge generation to process indoor VOCs, and carry out photocatalytic degradation by the ultraviolet light of discharge generation, to after water or the atomization of organic matter absorbent, mix with pollutant by ultrasonic wave, fully react at tourmaline load nano-titanium dioxide filling surface, the static behaviour that utilizes tourmaline to have, fully adsorbs residual contamination thing, and carries out catalytic oxidation.Accessory substance NOx and the O of exoelectrical reaction ₃pass through MnO ₂safe catalyst is removed.It is high that this method overcomes prior art cost of use, easily causes secondary pollution, the problem of poor processing effect.

A kind of improvement method of room air pollution, it is characterized in that comprising the following steps: blower fan is introduced air in discharge reactor, the module composition that discharge reactor is made up of bipolar needle electrode and nano titanic oxide catalyst net, air passes through MnO in discharge reactor outlet ₂safe catalyst, then after mixing with the water smoke of ultrasonic wave formation, enter fully reaction in filler, finally get back to indoor.

(1)use high direct voltage alternating expression bipolar needle electrode streamer-discahrge reactor, contaminated air is passed in discharge reactor, regulation voltage makes the anodal stable streamer that forms.

(2)the high energy electron bombardment air molecule that electrion produces makes gas band electric forming plasma, thereby being combined with plasma, contaminant particle (particularly PM2.5 particle) forms heavy ion, heavy ion moves to electrode under the effect of highfield, be attracted on electrode, needle plate electrode, due in the electric discharge of pin end, can be avoided the impact of electrode dust stratification.

(3)air is by rear plasma, hydroxyl radical free radical and the ozone etc. of forming of high energy electron bombardment, and VOCs can react and be eliminated with these materials.

(4)high pressure streamer-discahrge can produce strong ultraviolet light, and VOCs is subject to UV-irradiation after being adsorbed to photocatalyst surface, and photocatalyst surface forms electron hole, has strong oxidizing property, can oxidation Decomposition VOCs.

(5)owing to there being a large amount of nitrogen in air, when electric discharge, also can form NO ₂and O ₃, these accessory substances pass through MnO ₂safe catalyst is eliminated.

(6)remain untreated fall PM2.5 particle and after the organic solvent water smoke that produces of VOCs and ultrasound reactor mixes, enter packing area and react.Tourmaline appendix nano titanium oxide filler has very strong surface electrostatic, and adsorptivity is strong, and therefore residual contamination thing and water smoke are adsorbed to filling surface and fully react.

Brief description of the drawings

Fig. 1 is discharge reactor electrode pack module front view.

Fig. 2 is that the axles such as discharge reactor electrode pack module are surveyed view.

Detailed description of the invention

Air is introduced in streamer-discahrge reactor by blower fan, and reactor uses high-voltage DC power supply, and both positive and negative polarity is needle plate electrode, and the pin of both positive and negative polarity is staggered.Needle point 3 is 2 ~ 5cm to the distance of another utmost point pole plate 1, needle point 3 spacing 2 ~ 4cm on same electrode, and voltage swing is for being as the criterion the anodal streamer-discahrge that occurs.

Discharge reactor has modularization, and each module is made up of multi-group electrode plate, and what wherein pin number was more is positive plate 1, and what pin number was less is negative plate 2, and module is imported and exported two ends nano titanic oxide catalyst net 4.

In the time that air passes through discharge reactor, air molecule is by the rear plasma that forms of high energy electron bombardment, these high energy particle positively chargeds or negative point, can attract the particle of opposed polarity to form heavy ion, PM2.5 particle volume is increased, electric charge strengthens, and moves on other end electrode and settle down under the effect of highfield.

On the plate of needle plate electrode 1,2, have layer of titanium dioxide coating, the ultraviolet light that can absorb exoelectrical reaction generation carries out photocatalysis oxidation reaction, imports and exports and all has one deck nano titanium dioxide photocatalyst net at each group of electrode.

VOCs can be subject to exoelectrical reaction generation-OH base ,-O base, O after entering reactor ₃effect Deng strong oxidizer is decomposed, and due to the ultraviolet ray excited photochemical catalyst of discharge generation, forms electron hole on catalyst gauze simultaneously, and electron hole has strong oxidizing property, can decompose VOCs.

Owing to also there being N in air ₂and NOx, therefore also can produce side reaction

3O ₂(high pressure) → 2O ₃

N ₂+O ₂→2NO

2NO+O ₂→2NO ₂

NO+O ₃→NO ₂+O ₂

O ₃and NO ₂it is all harmful material.

When air passes through MnO in discharge reactor exit ₂safe catalysis net, MnO ₂can be by O ₃be converted into O ₂, by NO ₂be converted into NO ₃ ^-.

When air mixes by the organic matter absorbent water smoke producing with ultrasound reactor after safe catalysis net, enter packing area, tourmaline appendix nano titanium oxide filler has very strong surface electrostatic meeting adsorbing metal ions, charged dust etc., therefore pollutant fully reacts at filling surface with absorbent, remaining PM2.5 particulate and VOCs is absorbed after agent absorbs and is retained down by filler.

Claims

1. photocatalysis plasma body, in conjunction with an air-polluting method in ultrasonic wave process chamber, is characterized in that: comprise the following steps,

(1) utilize DC bipolar pin electrode discharge of plasma in low temperature reactor to produce plasma free radical, highfield and ultraviolet light;

(2) the high energy electron bombardment air molecule while utilizing discharge reactor to produce streamer, makes air molecule ionization, forms plasma, also can form a large amount of-OH, H simultaneously ₂o ₂, O ₃strong free radical;

(3) utilize the strong oxidizing property that the strong free radical of discharge generation has to decompose VOCs;

(4) ionized air and the PM2.5 particle formation heavy ion that can attract each other, heavy ion is finally caught by electrode to electrode movement under highfield effect, thereby separates from air;

(5) when discharge reactor produces streamer, can produce ultraviolet light, ultraviolet light meeting exciting light catalyst, forms electron hole, and the electron hole of formation has strong oxidizing property;

(6) after a part of VOCs is adsorbed by nano-photocatalyst, on catalyst, be degraded into harmless carbon dioxide and water;

(7) exoelectrical reaction also can form accessory substance NOx and O ₃, at MnO ₂under the effect of safe catalyst, be broken off;

(8) ultrasound reactor, by mixing with tail gas after water or the atomization of organic matter absorbent, enters packing area jointly, after the abundant mixed dissolution of filling surface, is held back and separates by filler, finally makes to export emission compliance.

2. in method according to claim 1, it is characterized in that discharge reactor uses DC high-voltage power supply, positive source connects anode plate, power cathode connects negative plates, and pole plate is needle plate electrode, and positive and negative pin electrode is staggered.

3. in method according to claim 1, it is characterized in that supply voltage just makes anodal streamer-discahrge, the just very more battery lead plate of pin number of forming.

4. according to claim 1 in method, it is characterized in that being coated with nano titanic oxide catalyst on both positive and negative polarity battery lead plate.

5. in method according to claim 1, it is characterized in that discharge reactor is made up of several equirotal electrode pack modules, modular electrode group is by several staggered to positive and negative needle plate electrode, and photochemical catalyst net is equipped with at electrode group two ends.

6. in method according to claim 1, it is characterized in that discharge reactor outlet is equipped with MnO ₂catalyst.

7. in method according to claim 1, it is characterized in that mixing with air after ultrasonic atomized water or organic matter absorbent.

8. in method according to claim 1, it is characterized in that the filler using is granular tourmaline appendix nano titanium oxide.