Oscillating Combustion Technology Being Evaluated as Method to Reduce NOx Emissions

Oscillating combustion technology currently being evaluated in the steel industry as a method to cost-effectively reduce NOx emissions from and increase productivity in high temperature, natural gas-fired furnaces.

DESCRIPTION OF METHOD
Oscillating combustion (U.S. Patent No. 4,846,665; European Patent No. 0524880A1) involves the creation of successive, NOx-formation-retarding, fuel-rich and fuel-lean zones within the furnace (see Fig. 1). This is accomplished by installing a high-speed oscillating valve on the fuel line at the burner. Heat is removed from the zones before they mix to reduce overall peak flame temperature, thus reducing NOx formation. Heat transfer from the flame to the load (and, therefore, furnace productivity) increases due to the more luminous fuel-rich zones and the breakup of the thermal boundary layer.