Simplified efficient process for reducing NOx, SOx, and particulates
March 16, 2015. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesControl of nitrogen oxides from stationary source effluents Method of introducing additive into a reaction gas flow Method for reduction of sulfur products in the exhaust gases of a combustion chamber Reduction of nitrogen-based pollutants through the use of urea solutions containing oxygenated hydrocarbon solvents Method and composition for utilizing lime-urea hydrates to simultaneously reduce NOx and SOx in combustion effluents Process for the reduction of nitrogen oxides in an effluent Use of oil-soluble surfactants in flue gas desulfurization systems Process for the reduction of nitrogen oxides in an effluent using sugar Process for reducing nitrogen oxides without generating nitrous oxide Process for controlling acid gas emissions in power plant flue gases InventorsAssigneeApplicationNo. 406206 filed on 03/16/1995US Classes:423/243.08, Alkali or alkali earth compound reactant110/345, Exhaust gas; e.g., pollution control, etc.423/235, Nitrogen or nitrogenous component423/243.01Utilizing aqueous reactant to remove or modify sulfur or sulfur containing componentExaminersPrimary: Langel, Wayne A.Assistant: Harding, Amy M. Attorney, Agent or FirmForeign Patent References
International ClassC01B 017/22AbstractThe removal of SOx and particulates, and preferably also NOx, from the combustion gases of a large boiler, is simplified while efficiency is improved. In a primary treatment zone, a slurry comprising an alkaline SOx -reducing composition and preferably a nitrogen-containing composition effective to reduce NOx, is introduced into combustion gases at a temperature of from about 900° to about 1300° C. The gases are cooled by initial contact with steam-generating means, and then by contact with an gas-to-gas heat exchanger. Cooled gases are then subjected to a secondary treatment in which they are first humidified and further cooled by introduction of a water spray or aerosol to reduce the temperature to 100° C. or below. Contact between the SOx -reducing composition and the humidified gases is maintained for a reaction period of at least 2 seconds. Particulate solids are then separated from the gases with a fabric filter. The cleaned gases are reheated by the gas-to-gas heat exchanger prior to discharge to the atmosphere. Reductions of SOx of greater than 80% are achieved, preferably 90 to 95%. |
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