Apparatus and method of reducing nitrogen oxide emissions
AssigneeConsolidated Natural Gas Service Company, Inc.
InventorsBernard P. Breen, James E. Gabrielson, Howard B. Lange
Life of this patent
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Abstract
An apparatus and method for reducing nitrogen oxide emissions from furnace flue gas is provided in which a pulse generator introduces natural gas, or other fluid fuel which has little or no fixed nitrogen, into the upper portion of the furnace. The fuel pulse reacts with the nitrogen oxide in the flue gas to form ammonia-like compounds and nitrogen gas. These ammonia-like compounds react with additional amounts of nitrogen oxide in the flue gas to form nitrogen gas, water vapor and carbon dioxide. In this manner, the amount of nitrogen oxide in the flue gas is reduced using a process which can be easily applied to retrofitted furnaces.
Claims7
An improved apparatus for reducing nitrogen oxide in flue gas in a furnace wherein a fuel is burned in a primary combustion zone to produce a flue gas containing nitrogen oxide wherein the improvement comprises:
- at least one pulse combustor attached to the furnace above the primary combustion zone which introduces into the flue gas pulses of a fluid selected from the group of fluids consisting of natural gas, C.sub.x H.sub.y compounds and C.sub.x H.sub.y O.sub.2 compounds and one of air, flue gas, and a combination of air and flue gas.
A method for reducing nitrogen oxide in flue gas comprising the step of:
- injecting pulses of a fluid selected from the group of fluids consisting of natural gas, C.sub.x H.sub.y compounds, C.sub.x H.sub.y O.sub.2 compounds, and mixtures primarily of these compounds into the flue gas in sufficient quantities to promote a reaction between the nitrogen oxide in the flue gas and the fluid to form ammonia compounds and N.sub.2 and to promote a secondary reaction of said ammonia compounds and additional nitrogen oxide from the flue gas to form N.sub.2, water and carbon dioxide.
A method for reducing nitrogen oxide in flue gas comprising the step of:
- injecting pulses of a mixture formed by the reaction between educted flue gas and a fluid selected from the group of compounds consisting of C.sub.x H.sub.y compounds, C.sub.x H.sub.y O.sub.2 compounds, and mixtures primarily of these compounds into the flue gas in sufficient quantities to promote a reaction between the nitrogen oxide in the flue gas and the fluid to form ammonia-like compounds and N.sub.2 and a secondary reaction of said ammonia-like compounds and additional nitrogen oxide from the flue gas to form N.sub.2, water and carbon dioxide.
Dependencies are inferred from the claim text.