Achieving Ultra-Low NOx Emissions in Methanol Downfired Reformer Applications

Paper from the AFRC 2013 conference titled Achieving Ultra-Low NOx Emissions in Methanol Downfired Reformer Applications by Rex Isaacs

Burner retrofits in downfired applications have proven to be challenging projects due to burner spacing requirements and resulting effects on burner flame quality. As the stringent environmental regulations continue to increase in the Kingdom of Saudi Arabia (KSA), there is a need to replace previous generations of burners with ultra-low NOx burners. A methanol producer in the Middle East operates a 2,900 MTPD plant that is designed to convert natural gas to methanol using Johnson Matthey technology. The steam methane reformer is fired by 234 downfired burners that are unable to meet the Royal Commission's NOx requirement (55 ng/J) at high plant rates. After a comprehensive evaluation, Zeeco's Next Generation Ultra-Low NOx Free-Jet Burner was selected to replace the existing burners. This ultra-low NOx burner technology produces a flame profile with very limited flame-to-flame interaction for burner installations, while also achieving shorter flame lengths within a small mechanical footprint. The Free-Jet Burner design utilizes the "free jet" mixing theory to maximize the amount of inert internal products of combustion mixed with the fuel gas to produce lower thermal NOx emissions. Zeeco will review the engineering details of the ultra-low NOx burners used in the retrofit application, provide specific retrofit installation details, lessons learned, and discuss verified successful field results.