Understand steam generator performance

Several variables affect the design and performance of packaged steam generators. Engineers should understand these parameters and their effects so that they can select cost-effective design options and write good specifications. Knowing how the steam parameters and efficiency vary with load can also help plant engineers plan their operation better. This article discusses the effects of such variables as excess air, fuel type, exit gas temperature, load, and emissions on generator design and operation. It also discusses some of the potential benefits of customized steam generators over standard, prepackaged designs, which often compromise on overall performance. The focus of the article is limited to gaseous and oil fuels.