Application of Dividing Wall Column in Silane Off-Gas Recovery Process: Optimal Design and Control

Dividing wall columns (DWCs) are one of the most popular units in the recent separation technology due to their high energy efficiency and low capital cost. This paper proposes a design method of DWC for separation of silane off-gas in the polysilicon manufacturing process, and the controllability of optimized process was investigated using dynamic simulation. The results show that the DWC can save 36% of the energy consumption and require smaller number of total stages. Especially, the total annual cost was reduced up to 17%. The method and concept proposed here will provide a basis for optimal design of other DWC systems.