Design and control of extractive distillation for the separation of methyl acetate-methanol-water

作者：Wang, Honghai; Ji, Pengyu; Cao, Huibin; Su, Weiyi; Li, Chunli^*

来源：Korean Journal of Chemical Engineering, 2018, 35(12): 2336-2347.

DOI：10.1007/s11814-018-0149-y

• Extractive Distillation
• Global Optimization
• Energy Saving
• Dynamic Control
• Control Scheme

The azeotrope of methyl acetate methanol and water was isolated using extractive distillation with water as entrainer. The pressure-swing extractive distillation (PSED) process and vapor side-stream distillation column (VSDC) with the rectifier process were designed to separate the methyl acetate, methanol and water mixture. It was revealed that the VSDC with the rectifier process had a reduction in energy consumption than the PSED process. Four control schemes of the two process were investigated: Double temperature control scheme (CS1), Q(R)/F feedforward control of reboiler duty scheme for PESD (CS2), Q(R)/F feedback control scheme for VSDC (CS3), the feedback control scheme of sensitive plate temperature of side-drawing distillation column to dominate the compressor shaft speed (CS4). Feed flow and composition disturbance were used to evaluate the dynamic performance. As a result, CS4 is a preferable choice for separation of methyl acetate-methanol-water mixture. A control scheme combining the operating parameters of dynamic equipment with the control indicators of static equipment was proposed in this paper. It means using the sensitive plate temperature of side-drawing column to control the compressor shaft speed. This is a new control scheme for extractive distillation.

• 出版日期2018-12
• 单位河北工业大学