Recent Achievements in Air Preheater Improvement

Recent Achievements in Air Preheater Improvement

In most generating units, the air preheater on a large utility boiler often accounts for over ١٠% of the unit’s thermal efficiency. From viewpoint of the thermal efficiency of a power plant, the air heater is a critical piece of equipment. Air preheater problems can lead to unit de-rates which result from fan capacity issues, improper combustion temperature and/or unacceptable gas temperatures entering the stack. Moreover proper flow of air and flue gas through air preheater increases combustion efficiency and decreases fan losses. In this paper, recent achievements in air preheater improvement are collected. These achievements are reduction in air preheater leakages by using high performance and adaptive seals and flexible contact sealing technology; better distribution of flow and heating surfaces by using self-repair and No-stick enamel and finally cleaning of air preheater coils by using pressurized liquid nitrogen.