The frequent cycling of a regenerative combustion system introduces nonlinearities and discontinuities that place challenges on a traditional combustion controls system. Several approaches can minimize these effects. This article will discuss some of these concepts, introducing strategies to simplify and improve control of a regenerative system. It also will describe factors that influence system design.
Regeneration is a common form of heat recovery originally developed in the 1850s — and vastly improved since then. It can yield combustion efficiencies as high as 75 percent on a gross heating value basis for a furnace temperature of 2000°F (1000°C). By contrast, for conventional cold-air firing, 30 to 35 percent combustion efficiency is common. With regenerative combustion systems, fuel usage for a given process can be less than required for other methods.