Urea reduction of NO.sub.x in combustion effluents
AssigneeElectric Power Research Institute, Inc.
InventorsJohn K. Arand, Lawrence J. Muzio, John G. Sotter
Life of this patent
Estimating the term…
Abstract
Method for reducing NO.sub.x in combustion effluents comprising introducing urea at elevated temperatures in the presence of oxygen, either as a solid or solution in amounts sufficient to reduce the NO.sub.x concentration. Conveniently, the urea may be introduced as a solid powder or as a solution in a hydroxylic solvent, at temperatures in excess of 1300.degree. F. and in the presence of at least 0.1 volume percent oxygen. This invention was made under contract with or supported by the Electric Power Research Institute.
Claims9
A process for selectively reducing NO.sub.x in a combustion effluent containing NO.sub.x comprising:
- contacting a NO.sub.x containing effluent stream in the presence of oxygen with urea, wherein said urea is present in an amount of about 0.1 to 10 moles per moles NO.sub.x at a temperature in the range of about 1600.degree. to 2000.degree. F. with the proviso that when an ancillary reducing material is introduced concurrently with the said urea, said temperature is in the range of about 1300.degree. to 2000.degree. F.
Dependencies are inferred from the claim text.