Modern boiler control and why digital systems are better

Steam generation in petrochemical plants and refineries is in a state of change. Expensive fuels have resulted in greater use of waste heat recovery boilers and other energy conservation measures. As a result, many conventional boilers have been mothballed. Improved flue gas analyzers and digital controls are replacing less efficient and less reliable control hardware. As the production of steam becomes decentralized, control systems needed to meet expanded plant objectives must be installed. Production, engineering and maintenance personnel are finding increased need to learn more about this specialized control area. This article will discuss conventional controls systems common in industrial boilers plus improvements made possible with currently available hardware.