Rigorous design and control of thermally integrated pressure-swing reactive distillation process for isobutyl acetate production considering the effect of column pressures

By studying the effect of pressure on relative volatility, azeotrope composition, and net reaction rate, a rigorous pressure-swing thermally integrated reactive distillation (PST-RD) process for isobutyl acetate synthesis is proposed. The steady-state and dynamic characteristics of the PST-RD process are evaluated based on Aspen and Aspen Dynamic. Steady-state optimization results show that the energy consumption and the total annual cost (TAC) reduced by 42.32% and 34.20% compared with the conventional two-column process, respectively. Subsequently, two control structures of the PST-RD process under a rigorous model are developed and evaluated by large disturbances in throughput and feed composition. Dynamic simulation results show that peak dynamic transients can be effectively reduced by adding a Q/F feedforward control structure. Furthermore, the effective heat integration of high-pressure (HP) and low-pressure (LP) columns can be realized by implementing composition/pressure cascade control when the capacity of the LP column increases.