ALTERNATE APPROACH TO TACKLE TURBOCHARGER UPGRADES FOR LOW EMISSIONS RETROFIT ON A LEGACY LARGE BORE, SLOW SPEED ENGINE
Operators of natural gas fired internal combustion engines continue to face increasingly stringent federal and state air regulations while striving to maintain engine operability and performance. Revitalization of existing horsepower often remains the most attractive approach technically and financially to meet both the air quality demands and operating flexibility in moving gas to meet market demands. Such conditions present the challenge to approach engineered solutions in alternate manners than OEMs often offer to meet lower emission levels and improved engine performance. This case study addresses the specific challenge of the required air specification based on engine type, location and state regulations. Pacific Gas & Electric faced reducing air emissions on a Cooper-Bessemer GMWC-10 engine at the Hinkley, California, compressor station in 2007-2008. The need to achieve low NOx and CO levels presented a challenge to apply coordinated emissions reduction technologies backed by ensuring the air delivery to the engine could be met across operating range of speed, load and in an environment of very high ambient temperatures.