CN1171664C

CN1171664C - Novel photocatalysis reactor for treating organic waste gas

Info

Publication number: CN1171664C
Application number: CNB021446733A
Authority: CN
Inventors: 孙德智; 段晓东; 朱质彬
Original assignee: Harbin Institute of Technology
Current assignee: Harbin Institute of Technology
Priority date: 2002-11-30
Filing date: 2002-11-30
Publication date: 2004-10-20
Anticipated expiration: 2022-11-30
Also published as: CN1415404A

Abstract

The present invention provides a novel photocatalysis reactor for treating organic waste gas, which relates to a gas purifying device, particularly to a purifying device for treating the organic waste gas which is difficult to degrade. The photocatalysis reactor comprises a casing (1), an ultraviolet lamp tube (2) arranged in the shaft center of the casing (1), isolation pieces (3) made of catalyst films, and barrel-shaped catalyst beds (4), wherein at least two catalyst beds (4) are arranged in the casing (1), and the isolation pieces (3) sheathed on the ultraviolet lamp tube (2) are inserted between the two catalyst beds (4); gaps (3-1) used for gas to flow are arranged on the isolation pieces (3), and the gaps (3-1) on the two adjacent isolation pieces (3) are mutually staggered. The photocatalysis reactor solves the problems of low utilization ratio of light energy, low catalytic activity, inconvenient installation of catalyzing devices, and inconvenient replacement of catalysts of the existing similar products. The photocatalysis reactor is mainly used for photocatalysis elimination of organic waste gas in closed and semi-closed human living spaces (such as living rooms, toilets, meeting rooms, sickrooms and recreation places) and production departments and pump rooms of factories.

Description

A kind of photo catalysis reactor that is used to handle organic exhaust gas

Technical field: the present invention relates to a kind of gas cleaning plant, particularly a kind of purifier of handling the difficult degradation organic exhaust gas.

Background technology: at present, the photo catalysis reactor that being used to of having reported handled waste gas has fixed-bed type and fluidized bed type, and is wherein in the majority with fixed bed photocatalytic reactor.Photochemical catalyst in the fixed bed photocatalytic reactor has graininess, cellular and fixing membranaceous, taken away by air-flow for fear of photocatalyst particles, often powder catalyst has been filled in the certain thickness bed reactor, because it is limited in one's ability that ultraviolet light penetrates beds, and most of catalyst can not be utilized, so its photocatalysis effect is relatively poor, and because particle nanoscale often in the beds, fill closely, its vapour lock is bigger; The photochemical catalyst that has is fixed in the photo catalysis reactor with cellular, though reduced vapour lock to a certain extent, exists the problem that most of catalyst can't obtain sufficient ultraviolet lighting too; The inwall that photocatalyst film is fixed on reactor that has, both avoided the graininess photochemical catalyst to be taken away by air-flow, overcome the unavailable defective of most of catalyst again, but do not consider in the design that air communication crosses the problem that short stream appears in reactor, short flow problem is particularly serious when handling big flow gas, causes the photocatalytic degradation effect not ideal enough.The fluidized bed photo catalysis reactor is with the fluidization in reactor of graininess photochemical catalyst, and with raising gas-affixed touching, but also there is the low shortcoming of light utilization efficiency in this kind reactor, and also has the problem serious to catalyst abrasion.Japan has announced RD81S type photocatalysis air purifying device in 1985.The catalytic bed of this device with the sheet ring set outside ultraviolet lamp tube, and and axis be certain angle, bed surface is bordering on parallel with light beam.Since light beam be not vertical irradiation on the catalyst face, so catalyst extinction efficient is lower, its catalytic activity is corresponding not high, and the installation of catalytic bed and catalyst are changed inconvenient.April nineteen ninety, the Kawashima etc. of the U.S. designed photocatalysis air purifying device, and its patent No. is 4,954,465, and it exists air flow path long, and treating capacity is little, and its structure is too complicated, was not easy to the shortcoming of installation and maintenance; And owing to adopt spherical ultraviolet source and plate catalytic bed structure, the ultraviolet efficiency of light energy utilization is low.1993, Li Qinglin etc. have released the patent of the light catalytic purifying device of the own intellectual property of China, its notification number is CN2114787U, its inside reactor structure has adopted tubular structure, and before the light-catalyzed reaction chamber, be provided with the active carbon adsorption section, this reactor can be used for handling low concentration (＜10ppm) small-molecule substance is (as NH ₃, H ₂S, CH ₃SH), the also big (1.5M of processing flux ³/ min), treatment effeciency is higher, but mainly rely on the suction-operated of active carbon adsorption section for the removal of difficult degradation organic macromolecule material (as the benzene series thing), photo catalysis reactor is little to the contribution of its removal, and the long-term problem of using the regeneration and the replacing that exist activated carbon.

Summary of the invention: the invention provides a kind of photo catalysis reactor that is used to handle organic exhaust gas, the efficiency of light energy utilization that it has solved existing like product existence is low, catalytic activity is low, catalyst converter is installed and catalyst is changed inconvenient problem.Photo catalysis reactor of the present invention includes housing 1, is arranged on the ultraviolet lamp tube 2 of housing 1 shaft core position, the partition 3 that catalyst film is made, the catalyst bed 4 of tubular, at least two catalyst beds 4 are arranged in the housing 1, the partition 3 that is sleeved on the ultraviolet lamp tube 2 is inserted between two catalyst beds 4, have the breach 3-1 that makes gas communication on partition 3, the breach 3-1 on the two adjacent partitions 3 staggers mutually.The present invention since ultraviolet lamp tube 2 can vertical irradiation on catalyst bed 4, thereby the efficiency of light energy utilization is higher.And be enclosed within partition 3 on the ultraviolet lamp tube 2 as barrier, can make air-flow be snakelike in reactor flows, make air-flow under axially and radially the diverse location catalytic film restricts, fully clash into and the contact catalysis agent film, strengthened the contact effect of air-flow with catalyst film, avoid the air-flow short circuit, helped the raising of catalyst activity.Photo catalysis reactor of the present invention is mainly used in the workshop of sealing and semiclosed human living space (as: room, toilet, meeting room, ward and public place of entertainment) and factory, the photocatalysis of the organic exhaust gas in the pump house is eliminated.Catalyst bed 4 in the reactor of the present invention is fixed with catalyst film 4-2 and constitutes on the ring support 4-1 that stainless steel wire is made, therefore be convenient to integral installation and replacing.Catalyst film of the present invention is to be carrier with the XPM, as catalyst, uses colloidal sol with iron-doped titanic oxide---gel method is prepared from, and the porosity of XPM is 85～95%.But this catalyst film high-efficiency and continuous is handled difficult degradation organic exhaust gas (as benzene series thing, gasoline etc.), the loose structure of carrier has enlarged the surface area of catalyst effectively, processed air-flow can more effectively contact with catalyst in the reactor, therefore can effectively degrade to organic compounds.In addition, this photo catalysis reactor have the air-flow flux big, be easy to the advantage installing and change.The present invention is directed to the defective of the version of existing several photo catalysis reactors at present, carried out more reasonably design and improvement.The radially spacing blade inserting of partition 3 and catalyst bed 4 is arranged, make air-flow snakelike flowing in reactor, both strengthened fully contacting of air-flow and beds, promote light-catalyzed reaction effectively, can make reactor have big flux again, solid preferably resolve gas-good contact (mass transfer) and the contradiction between vapour lock.Compare with the patent of photo catalysis reactor known today, have more rational structure and the better effect of the big molecule organic gas of processing difficult degradation.

Description of drawings: Fig. 1 is the overall structure schematic diagram of photo catalysis reactor in the specific embodiment, and Fig. 2 is the A-A cutaway view of Fig. 1, and Fig. 3 is the structural representation of a plurality of catalytic beds 4, and Fig. 4 is the B-B cutaway view of Fig. 3.

The specific embodiment: present embodiment is made up of housing 1, ultraviolet lamp tube 2, the partition 3 that catalyst film is made, catalyst bed 4, blender 5 and the humidifier 6 of tubular, housing 1 is connected with capping 1-2 respectively at cylinder outer race 1-1 two ends and forms, and is respectively equipped with air inlet 1-3 and gas outlet 1-4 on two capping 1-2.Outer end at air inlet 1-3 also is connected with blender 5, on the support 5-1 in the blender 5 blower fan 5-2 is installed, and in the inboard of the air entry 5-3 of blender 5 humidifier 6 is installed also.Blender 5 mixes organic exhaust gas and steam, with the relative humidity of control waste gas.Ultraviolet lamp tube 2 is arranged on the shaft core position of housing 1.Catalyst bed 4 is made up of ring support 4-1 and catalyst film 4-2, and ring support 4-1 encircles 4-3, the right 4-4 of ring by a left side and forms with the straight steel wire 4-5 that two rings are linked to each other, and catalyst film 4-2 twines solid outside at ring support 4-1.A plurality of catalyst beds 4 are arranged side by side in housing 1, and its outer surface is close to the inwall of housing 1, and two adjacent catalyst beds 4 link to each other by an arc silk 7 in a side, make and form a gap between two catalyst beds 4.The edge that is sleeved on a plurality of partitions 3 on the ultraviolet lamp tube 2 is inserted in respectively in the gap between each catalyst bed 4, and breach 3-1 opens in the limit of partition 3 one, forms 160 °～180 ° corner between the breach 3-1 on the two adjacent partitions 3, and the best is 180 °.Catalyst film 4-2 is a carrier with the XPM all with the catalyst film of making partition 3, as catalyst, uses colloidal sol with iron-doped titanic oxide--gel method is prepared from.The porosity of XPM is 90%, and described iron-doped titanic oxide is that to add quality in titanium dioxide be 0.06%～0.08% molysite, and described molysite is ferric sulfate or ferric nitrate, and iron-doped titanic oxide can improve activity of such catalysts.In use also can be with titanium dioxide as catalyst.It is the uviol lamp of 254nm that the used light source of present embodiment adopts dominant wavelength, not only helps light-catalyzed reaction, also can kill airborne virus and bacterium.The total power consumption of blower fan is 25W in the light source of the photo catalysis reactor that the present invention is designed and the blender.The treating capacity of organic exhaust gas is 0.5m ³/ min.Is 1000mg/m with this photo catalysis reactor for containing benzene,toluene,xylene concentration ³Room air, be 0.5m at flow ³During/min, controlled humidity is 45%, all is lower than 25mg/m through three kinds of organic exhaust gas concentration of photocatalysis treatment reactor outlet ³, be lower than national standard (＜100mg/m ³), degradation rate is greater than 95%.The airborne gasoline gas concentration of certain pump house is 2300mg/m ³, be 0.5m at flow ³During/min, controlled humidity is 60%, is lower than 50mg/m through photocatalysis treatment post-reactor outlet gasoline gas concentration ³, degradation rate surpasses 97%.

Claims

1, a kind of photo catalysis reactor that is used to handle organic exhaust gas, it includes housing (1), be arranged on the ultraviolet lamp tube (2) of housing (1) shaft core position, the partition (3) that catalyst film is made, the catalyst bed (4) of tubular, it is characterized in that at least two catalyst beds (4) are arranged in the housing (1), the partition (3) that is sleeved on the ultraviolet lamp tube (2) is inserted between two catalyst beds (4), have the breach (3-1) that makes gas communication on partition (3), the breach (3-1) on adjacent two partitions (3) staggers mutually.

2, a kind of photo catalysis reactor that is used to handle organic exhaust gas according to claim 1 is characterized in that catalyst bed (4) is to be fixed with catalyst film (4-2) and to constitute on the ring support (4-1) that stainless steel wire is made.

3, a kind of photo catalysis reactor that is used to handle organic exhaust gas according to claim 1 and 2 is characterized in that catalyst film is is carrier with the XPM, as catalyst, uses colloidal sol with iron-doped titanic oxide---gel method is prepared from.

4, a kind of photo catalysis reactor that is used to handle organic exhaust gas according to claim 3, the porosity that it is characterized in that XPM is 85～95%.

5, a kind of photo catalysis reactor that is used to handle organic exhaust gas according to claim 3 is characterized in that described iron-doped titanic oxide is that to add quality in titanium dioxide be 0.06%～0.08% molysite.

6, a kind of photo catalysis reactor that is used to handle organic exhaust gas according to claim 5 is characterized in that described molysite is ferric sulfate or ferric nitrate.

7, a kind of photo catalysis reactor that is used to handle organic exhaust gas according to claim 1, it is characterized in that housing (1) is connected with capping (1-2) respectively at cylinder outer race (1-1) two ends and forms, and is respectively equipped with air inlet (1-3) and gas outlet (1-4) in two cappings (1-2).

8, a kind of photo catalysis reactor that is used to handle organic exhaust gas according to claim 7, it is characterized in that also being connected with blender (5) in the outer end of air inlet (1-3), on the support (5-1) in the blender (5) blower fan (5-2) is installed, humidifier (6) also is installed in the inboard of the air entry (5-3) of blender (5).

9, a kind of photo catalysis reactor that is used to handle organic exhaust gas according to claim 1 is characterized in that breach (3-1) opens the limit portion at partition (3), forms 160 °～180 ° corner between the breach (3-1) on adjacent two partitions (3).