A phenomenological analysis of particulate solids in the operation of rotary reactors

摘要

Rotary reactors are regarded as mature unit operations that may be found in industries as diverse as chemical, mineral processing, metallurgical, and nuclear. These reactors often present a very hostile chemical and physical processing environment involving high temperature continuous operation of particulate solids whose size, distribution, chemical constituents and shape evolve as they travel through the reactor. Despite the use of these reactors for almost a century, little quantitative knowledge exists about the behavior and reactivity of the solids feed under actual processing conditions. Hence, the application of some of these reactors result in failed designs, while those successfully implemented to not always reach their full potential of product consistency, energy efficiency, and optimum producitivty. This paper will present examples where the behavior of particulate solids has been elucidated and was used to describe their phenomenological behavior in these reactors. In a number of case studies this knowledge is used to develop models that accurately simulate processing in these unit operations. These studies will include uranium oxide reduction and coal pyrolysis. Areas where there remains challenges to quantitatively represent particulate behavior will also be presented.