# US 8,772,015 B2 · Biofilter media to remove odour causing compounds from waste gas streams > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,772,015 B2 - Document ID: US8772015B2 - Status: Granted - Kind: B2 - Application number: 12/245,327 - Filed: 2008-10-03 - Published: 2009-04-09 - Granted: 2014-07-08 - Earliest claimed: 2007-10-04 - Assignees: Biorem Technologies Inc. - Applicants: Hidayat Husain; Brian P. Herner - Inventors: Hidayat Husain; Brian P. Herner - Web page: https://patentgrep.com/patent/US8772015B2 ## CPC - B01D 53/85: with gas-solid contact - B01D 53/84: Biological processes - B01D 53/77: Liquid phase processes - B01D 2251/104: Ozone - B01D 2251/95: Specific microorganisms - B01D 2257/2064: Chlorine - B01D 2257/304: Hydrogen sulfide - B01D 2257/306: Organic sulfur compounds, e.g. mercaptans - B01D 2257/40: Nitrogen compounds - B01D 2257/406: Ammonia - B01D 2257/70: Organic compounds not provided for in groups B01D2257/00 - B01D2257/602 - B01D 2257/708: Volatile organic compounds V.O.C.'s - B01D 2257/90: Odorous compounds not provided for in groups B01D2257/00 - B01D2257/708 - B01D 2259/804: UV light - Y02A 50/20: Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters - 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) - Y02A: TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE ## Abstract A biofilter media has one or more of a set of desired physical characteristics. The set of physical characteristics includes a sphericity of 0.75 to 1, a particle size of 1 to 16 or 4 to 8 mm, a uniformity coefficient of 2 or less and a surface area of 800 to 2000 m2/m3 of media. The media is coated, supports microorganisms and is used to treat a waste gas stream. ## Claims ### Claim 1 A process for removing contaminants from a gas stream, the process comprising, a) providing a biofilter having a medium, the medium comprising granules, wherein each granule comprises a core and a coating, wherein the granules or their cores have a sphericity of 0.75 to 1, a particle size of 1 to 16 mm and a uniformity coefficient of between 1 and 2, wherein the biofilter further comprises microorganisms; and, b) flowing the gas stream through the biofilter at a rate providing an empty bed residence time (EBRT) of 15 seconds or less, wherein the contaminants comprise hydrogen sulfide, a volatile organic compound or a reduced sulfur compound, and wherein the coating includes one or more of a bonding agent, an adsorptive agent, and nutrients for the microorganisms. ### Claim 2 (depends on 1) The process of claim 1, wherein the medium consists essentially of granules or their cores that have a particle size of 8 mm or less. ### Claim 3 (depends on 2) The process of claim 2, wherein the granules or their cores have a sphericity of 0.8 to 1. ### Claim 4 (depends on 3) The process of claim 3, wherein the granules or their cores have a surface area of 800 to 2,000 m2/m3 of the medium. ### Claim 5 (depends on 4) The process of claim 4, wherein the granules or their cores have a surface area of 1,000 to 1,500 m2/m3 of the medium. ### Claim 6 (depends on 5) The process of claim 5, wherein the core is an expanded glass particle. ### Claim 7 A process for removing contaminants from a gas stream, the process comprising, a) providing a biofilter having a medium, the medium comprising granules, wherein each granule compromises a core and a coating, wherein the granules or their cores have a sphericity of 0.75 to 1, a uniformity coefficient of between 1 and 1.5 and a particle size of 1 to 16 mm, wherein the biofilter further comprises microorganisms; and, b) flowing the gas stream through the biofilter at a rate providing an empty bed residence time (EBRT) of 20 seconds or less, wherein the contaminants comprise hydrogen sulfide, a volatile organic compound or a reduced sulfur compound; and wherein 80% or more of the granules or their cores are of a size that would be retained between square grid sieves having openings differing in width by 4 mm or less. ### Claim 8 (depends on 7) The process of claim 7, wherein the sieves comprise one sieve with 4 mm openings and another sieve with 8 mm openings. ### Claim 9 (depends on 1) The process of claim 1, wherein the granules or their cores have a uniformity coefficient of between 1 and 1.5. ### Claim 10 (depends on 1) The process of claim 1, wherein the coating comprises a bonding agent, an adsorptive agent and nutrients for the microorganisms. ### Claim 11 (depends on 6) The process of claim 6, wherein the expanded glass comprises silica and at least one alkali oxide. ### Claim 12 (depends on 7) The process of claim 7, wherein the granules or their cores have a sphericity of 0.8 to 1. ### Claim 13 (depends on 8) The process of claim 8, wherein the granules or their cores have a surface area of 1,000 to 1500 m2/m3 of the medium, and a sphericity of 0.8 to 1.