# US 11,298,657 B2 · Hot-side method and system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,298,657 B2 - Document ID: US11298657B2 - Status: Granted - Kind: B2 - Application number: 16/910,901 - Filed: 2020-06-24 - Published: 2021-01-07 - Granted: 2022-04-12 - Earliest claimed: 2010-10-25 - Assignees: ADA-ES, Inc. - Applicants: ADA-ES, Inc. - Inventors: Michael D. Durham; Sharon Sjostrom; Kenneth E. Baldrey - Web page: https://patentgrep.com/patent/US11298657B2 ## CPC - B01D 53/96: Regeneration, reactivation or recycling of reactants - B01D 53/64: Heavy metals or compounds thereof, e.g. mercury - B01D 53/78: with gas-liquid contact - F23J 7/00: Arrangement of devices for supplying chemicals to fire - F23J 15/006: {Layout of treatment plant} - F23J 15/02: of purifiers, e.g. for removing noxious material (traps for solid residues F23J3/04) - F23J 15/022: {for removing solid particulate material from the gasflow} - F23J 15/04: using washing fluids {(scrubbers for removing solids only F23J15/022)} - B01D 2251/108: Halogens or halogen compounds - B01D 2253/1124: Metal oxides - B01D 2257/602: Mercury or mercury compounds - B01D 2258/0283: Flue gases - F23J 2215/30: Halogen; Compounds thereof - F23J 2215/60: Heavy metals; Compounds thereof - 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) - F23J: REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES (combustion apparatus for consuming smoke or fumes, e.g. exhaust gases, F23G7/06) ## Abstract The present disclosure is directed to the use of elemental or speciated iodine and bromine to control total mercury emissions. ## Claims ### Claim 1 A method, comprising: generating from a mercury-containing feed material a mercury-containing gas stream comprising vapor-phase elemental mercury and a vapor-phase halogen; passing the mercury-containing gas stream through a scrubber to remove, from the mercury-containing gas stream, at least a portion of the vapor-phase halogen and/or a halogen-containing derivative thereof and form a halogen-containing scrubbing medium and a treated gas stream; and removing a halogen from the halogen-containing scrubbing medium to form a treated scrubbing medium for recycle to the scrubber and a removed halogen and/or halogen-containing material comprising the removed halogen. ### Claim 2 (depends on 1) The method of claim 1, wherein the halogen in the removed halogen and/or halogen-containing material is one or more of bromine and iodine and wherein the scrubber is a wet or dry scrubber. ### Claim 3 (depends on 1) The method of claim 1, wherein the scrubber removes at least most of the vapor-phase halogen from the mercury-containing gas stream and wherein the scrubber removes at least most of an acid gas from the mercury-containing gas stream. ### Claim 4 (depends on 1) The method of claim 1, wherein at least most of the halogen in the halogen-containing scrubbing medium is removed as the removed halogen and/or halogen-containing material. ### Claim 5 (depends on 1) The method of claim 1, wherein the scrubber is a wet scrubber and is capable of removing one or more of HCl, HBr, and HF from the mercury-containing gas stream. ### Claim 6 (depends on 1) The method of claim 1, wherein the halogen is removed from the halogen-containing scrubbing medium by one or more of membrane separation, precipitation, adsorption, and/or absorption. ### Claim 7 (depends on 6) The method of claim 6, wherein the halogen-containing scrubbing medium is contacted with an oxidant to assist halogen removal. ### Claim 8 (depends on 1) The method of claim 1, wherein the scrubber is a wet scrubber and wherein the halogen is removed from the halogen-containing scrubbing medium by one or more of an ion exchange resin, solvent extraction, adsorption, absorption, precipitation, and membrane filtration. ### Claim 9 (depends on 1) The method of claim 1, wherein the halogen can oxidize elemental mercury in the mercury-containing gas stream and further comprising: recycling the removed halogen and/or halogen-containing material to the generating, whereby the vapor-phase halogen is derived from the removed halogen and/or halogen-containing material. ### Claim 10 (depends on 9) The method of claim 9, further comprising regenerating the removed halogen and/or halogen-containing material prior to recycle. ### Claim 11 (depends on 1) The method of claim 1, wherein a concentration of the vapor-phase halogen in the treated gas stream is no more than about 25 ppm. ### Claim 12 (depends on 1) The method of claim 1, wherein the vapor-phase halogen is iodide. ### Claim 13 (depends on 1) The method of claim 1, wherein the vapor-phase halogen is bromide. ### Claim 14 (depends on 1) The method of claim 1, wherein the mercury-containing feed material is coal, wherein the mercury-containing gas stream is formed by combusting coal and wherein the vapor-phase halogen is formed from a native halogen-content of the coal. ### Claim 15 (depends on 1) The method of claim 1, wherein the mercury-containing feed material is coal, wherein the mercury-containing gas stream is formed by combusting coal, and wherein the vapor-phase halogen is formed from a halogen-containing additive combusted with the coal. ### Claim 16 (depends on 1) The method of claim 1, wherein the mercury-containing feed material is coal, wherein the mercury-containing gas stream is formed by combusting coal, and wherein the vapor-phase halogen is introduced into the mercury-containing gas stream downstream of a coal combustion zone.