Understand boiler performance characteristics

An understanding of the major differences in performance characteristics of steam generators is essential to better use and integrate them into plant steam systems. Process and cogeneration plants widely use gas- or oil-fired packaged steam generators and gas-turbine-exhaust, heat-recovery steam generators to meet steam demands. The most important differences are efficiency versus load characteristics, gas/steam temperature profiles and partial load behavior. Also, steaming in the economizer is a concern at low steam flows for HRSGs, but not for packaged boilers. The paper describes packaged boilers, how emissions impact design of packaged boilers, completely water-cooled furnace, superheater design, packaged boiler performance characteristics, heat-recovery steam generators, and basic differences between HRSGs and packaged boilers.