T-fired retrofit cuts lignite NOx

Compared to tangential fired units burning bituminous coal, lignite-fueled tangential units have unique design and operating requirements that need to be anticipated for a successful retrofit to low-NOx operation. The conversion made by Cooperative Power/United Power Association on their 550 MW, lignite-fired Coal Creek Unit#2 to low-NOx firing using Foster Wheeler Energy Corporation's tangential low NOx (TLN) system is presented. With this conversion, emissions performance and furnace operating conditions both improved. This retrofit represents an important milestone for tangential low-NOx technology and serves as a forerunner for future low-NOx conversions involving low-rank coal.