Combustion Optimization - NOxTrol

NOxTrol is ABB's advanced system for reducing NOx emissions on tangentially fired units with over-fire air. Our continuous-monitoring system maintains an optimal stoichiometry profile in the furnace during dynamic events such as boiler load swings. In addition, NOxTrol enables operators to make changes to the firing system without violating emission standards.

The system responds to these changes rapidly, to keep NOx emissions under control without sacrificing efficiency. NOxTrol utilizes over-fire air adjustment in the furnace to reduce emissions. This has proved to be the most effective means of reducing NOx, while maintaining optimal combustion conditions.

NOxTrol can be used on boilers burning coal, oil, or gas. As a stand-alone installation within the DCS, a load-indexed demand value or bias determines main burner zone stoichiometry. As part of an integrated Combustion Optimization system, a stoichiometry set-point from the Neural Net system provides smart set-points for total system control.

In this configuration, NOxTrol acts as the inner loop of an advanced cascade control scheme.