A Distributed Control Application for Continuous Drying

This paper describes the control of continuous drying with the use of distributed process controls utilizing simple function blocks. The physical principles of continuous drying are reviewed. A control strategy for an adiabatic dryer is proposed. Preheater and heat recovery sections are included for high energy efficiency and desirable end product quality. Furthermore, supervisory controls to coordinate the feed rate of the product, steam flow of the preheater, and the firing rate of combustion are presented. Implementation by distributed process controls is discussed.