Burners used in Kern County, Calif., oil fields have achieved sub-5 ppm NOXemissions with combustion stability on multiple once-through steam generators.

According to Coen Inc., the San Mateo, Calif., manufacturer that supplied the burners, new restrictions in the state's San Joaquin Valley require operation with less than 7 ppm NOX. In addition, standards are expected to become more stringent in the near future, to less than 5 ppm NOX, Coen notes. To remain California-based industrial processors need reliable combustion technologies that can meet and exceed environmental performance standards.

Coen markets a burner, the QLN-II, that it says can meet these requirements. The burner allows latitude in deviations of induced flue-gas recirculation (FGR) and excess air rates without developing combustion instabilities, according to Coen. The amount of FGR necessary for NOXcontrol in the Coen burner is lower than what is required typically by premixed ultra-low NOXburners for achieving comparable emissions, says the company.