Control Strategy For A Multiple Hearth Furnace

This paper presents and discusses a mineralogy-driven control strategy for a multiple hearth furnace in kaolin production. The objective of the advanced control is to maximize capacity and to minimize energy consumption while preserving the desired product quality. The control is based on two main soft sensors: the mullite content indicator for capacity improvement and the spinel phase reaction rate indicator for energy use reduction. In this simulation study, the control strategy is tested and compared with an industrial controller based on a proportional-integral scheme as a benchmark. The results show that the capacity of the process is significantly improved and the energy use is notably diminished.