# US 10,478,517 B2 · Method and apparatus for purging unwanted substances from air > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,478,517 B2 - Document ID: US10478517B2 - Status: Granted - Kind: B2 - Application number: 14/046,641 - Filed: 2013-10-04 - Published: 2014-02-06 - Granted: 2019-11-19 - Earliest claimed: 2008-09-19 - Assignees: FIPAK Research And Development Company - Applicants: FIPAK Research and Development Company; Marie Hauville - Inventors: Francois Hauville; Cédric Herry - Web page: https://patentgrep.com/patent/US10478517B2 ## CPC - A61L 9/22: Ionisation - B01D 53/75: Multi-step processes - B01D 53/90: Injecting reactants - B01D 53/323: {by electrostatic effects or by high-voltage electric fields} - B01D 53/864: {Removing carbon monoxide or hydrocarbons} - B01D 53/8675: {Ozone} - B01D 2255/1021: Platinum - B01D 2255/106: Gold - B01D 2255/2073: Manganese - B01D 2255/20761: Copper - B01D 2259/818: Employing electrical discharges or the generation of a plasma - B08B 15/023: {Fume cabinets or cupboards, e.g. for laboratories} - A61L: METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES (preservation of bodies or disinfecting characterised by the agents employed A01N; preserving, e.g. sterilising, food or foodstuffs A23; preparations for medical, dental or toiletry purposes A61K) - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - B08B: CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL ## Abstract Apparatus comprising: a fumehood; and an air treatment device for purging unwanted substances from the exhaust air of the fumehood, the air treatment device comprising: a non-thermal plasma reactor stage for producing air byproducts comprising O., N., OH. and O3 and introducing those air byproducts into the exhaust air of the fumehood so as to treat the exhaust air of the fumehood; and a catalyst stage downstream of the non-thermal plasma reactor stage for further treating the air downstream of the non-thermal plasma reactor stage. ## Claims ### Claim 1 A method for purging unwanted substances from air, the method comprising: providing apparatus comprising: a fumehood comprising a protective enclosure for safely handling hazardous substances, and an exhaust vent for venting exhaust air from the protective enclosure of the fumehood; and an air treatment device for purging unwanted substances from the exhaust air of the fumehood, the air treatment device comprising: a non-thermal plasma reactor stage comprising an air inlet for receiving the air to be treated in the non-thermal plasma reactor stage, a plurality of separate non-thermal plasma reactor units for dividing the air to be treated into a plurality of chambers and simultaneously treating the air in each of the plurality of chambers, and an air outlet for exhausting the treated air from the non-thermal plasma reactor stage; wherein each of the plurality of separate non-thermal plasma reactor units comprises a dielectric barrier discharge construction, wherein the dielectric barrier discharge construction comprises a first electrode and a second electrode, with the first electrode of one of the plurality of separate non-thermal plasma reactor units being separated by a dielectric plate from the second electrode of the same one of the plurality of separate non-thermal plasma reactor units, and further wherein the air within one of the non-thermal plasma reactor units is separated from the air within another of the non-thermal plasma reactor units; wherein the plurality of separate non-thermal plasma reactor units are assembled together in parallel so as to form a collective cross-section equal in size to the air inlet of the non-thermal plasma reactor stage and equal in size to the air outlet of the non-thermal plasma reactor stage, and further wherein the air entering the air inlet is divided between the plurality of separate non-thermal plasma reactor units; and a catalyst stage, wherein the catalyst stage is formed separately from the non-thermal plasma reactor stage and located downstream from the non-thermal plasma reactor stage; and operating the fumehood, wherein operating the fumehood comprises: passing the exhaust air of the fumehood through the non-thermal plasma reactor stage of the air treatment device, wherein the air is passed through the air inlet, divided between the plurality of separate non-thermal plasma reactor units and passed out the air outlet, with the divided air simultaneously passing through the plurality of separate non-thermal plasma reactor units so as to provide treated exhaust air; and passing the treated exhaust air through the catalyst stage. ### Claim 2 (depends on 1) A method according to claim 1 wherein a potential difference applied across the first electrode and the second electrode comprises electric pulses at a frequency of 50 Hz to 2000 Hz. ### Claim 3 (depends on 1) A method according to claim 1 wherein the catalyst stage comprises MnO2. ### Claim 4 (depends on 3) A method according to claim 3 wherein at least one of the plurality of non-thermal plasma reactor units comprises a coronal tube comprising a wire electrode and a cylinder electrode disposed around the wire electrode. ### Claim 5 (depends on 4) A method according to claim 4 wherein the wire electrode and the cylinder electrode are disposed coaxially. ### Claim 6 (depends on 4) A method according to claim 4 wherein the non-thermal plasma reactor unit is driven by electrical pulses, and further wherein the electrical pulses are regulated to minimize arcing. ### Claim 7 (depends on 1) A method according to claim 1 wherein at least one of the plurality of non-thermal plasma reactor units comprises a wire electrode, a cylinder electrode disposed around the wire electrode, and a cylinder dielectric disposed between the wire electrode and the cylinder electrode. ### Claim 8 (depends on 7) A method according to claim 7 wherein the wire electrode, the cylinder electrode and the cylinder dielectric are disposed coaxially. ### Claim 9 (depends on 1) A method according to claim 1 wherein the first electrode comprises a wire electrode and the second electrode comprises a plate electrode, and the dielectric plate is disposed between the wire electrode and the plate electrode. ### Claim 10 (depends on 1) A method according to claim 1 wherein at least one of the plurality of non-thermal plasma reactor units comprises a first plate electrode, a second plate electrode, and a plate dielectric disposed between the first plate electrode and the second plate electrode. ### Claim 11 (depends on 3) A method according to claim 3 wherein the catalyst stage further comprises CuO. ### Claim 12 (depends on 3) A method according to claim 3 wherein the catalyst stage comprises a plurality of different catalysts. ### Claim 13 (depends on 3) A method according to claim 3 further comprising a filter located upstream of the non-thermal plasma reactor stage. ### Claim 14 (depends on 3) A method according to claim 3 further comprising a filter located downstream of the catalyst stage.