Catalytic combustion offers gas turbines and other large combustion systems the potential to achieve high flame stability (with near-zero hydrocarbon and carbon monoxide emissions) while also operating cool enough to have near-zero NOx emissions. The result can be ultra-low emissions without efficiency penalty or the costs of post-combustion NOx controls, as well as substantially broadened low NOx turndown arising from improved flame stability. Compared to the high costs of implementing post-combustion controls, our catalytic combuustor offers significant economic advantage to the combustor owner.
Dr. William Pfefferle, PCI’s chief scientist, invented the original catalytic combustor. Over time, many parties have explored the concept but a perennial challenge to making commercial catalytic combustors has been the difficulty in achieving both high enough catalytic reaction while simultaneously avoiding catalytic over-reaction. PCI’s patented technology is a breakthrough in this area that unlocks the long sought potential of catalytic combustion.
Conventionally, lean premixed combustion, the current dominant gas turbine combustor technology, balances high flame stability against cool maximum firing temperatures, achieving near-zero hydrocarbon and carbon monoxide levels while producing NOx in the high single digit ppm range. If low single digit ppm NOx standards are to be met, then post-combustion controls such as selective catalytic reduction (SCR) systems are used.
The Catalytic combustor (sometimes called a catalytically-stabilized combustor) increases gas phase combustion stability by catalytically reacting a portion of the fuel, increasing overall gas phase reactivity and flame speed. Reacting a portion of the fuel in the catalytic region of the combustor improves flame stability as well as creating the conditions for more rapid, complete combustion. Extending flame stability provides many opportunities for gas turbines including the ability to burn lean enough to avoid NOx formation as well as achieve extended low NOx turndown. In the case of PCI’s technology, the combustor’s fuel flexibility is also substantially broadened, plus the technology can burn low BTU fuels that otherwise would require supplementation.
PCI is developing its RCL® catalytic combustion technology in several designs for ultra-low emission power generation gas turbines. PCI’s full catalytic combustors seek to minimize NOx emissions from gas turbines, while its catalytic pilot burners are a partially catalytic design that is easy to implement into existing lean premixed/dry low NOx designs. Our microturbine catalytic combustor addresses the unique needs of microturbines. Our downhole catalytic combustor/steam generator adapts RCL® technology for use downhole in an oil or gas production wellbore to provide thermal stimulation for production of oil and gas. PCI’s oxyfuel combustor is directed to achieving effective combustion of oxygen and fuel in the presence of steam in IGCC and related systems.
Contact PCI to learn more about how our solutions may be adapted for your needs.
