The Real Cost of NOx Emission Reduction

Clean air legislation in the United States will continue to mandate reductions in the quantities of nitrogen oxides emitted by process heaters, boilers and gas turbines in petrochemical plants. Regulations have been implemented that require not only point source reductions, but overall plant wide reduction of nitrogen oxides. Retrofitting existing fired units to reduce their emissions is often a challenging task for the engineer and designer Available technologies can be used in different applications resulting in significantly different reductions and cost. This paper describes the various constraints faced by engineers in applying present NOx reduction technology to process heaters, boilers, and gas turbines, along with their associated cost. Overall installation cost is evaluated along with nitrogen oxide reduction to determine which technologies are most cost effective in achieving compliance