气相进料对隔板精馏塔优化设计的影响

Influence of vapor feed on optimal design of dividing wall column

隔板精馏塔(DWC)在节能和节省设备投资方面具有十分突出的优势,隔板精馏塔中隔板位置是重要的设计变量,影响分离效果及能耗,当进料中含有气相时这种影响更加显著。选用苯、甲苯和对二甲苯三元物系,研究了进料的气相分率对隔板位置的影响并确定最优隔板位置。采用严格模拟方法,以年度总费用(TAC)为评价指标,比较不同进料气相分率下隔板塔的经济性,其中气相进料较液相进料TAC最高可节省23.33%。并通过灵敏度分析展示了在进料中含有气相时确定最优隔板位置的重要性。

Dividing wall column(DWC) has outstanding advantages in terms of energy saving and investment cost for distillation separation. The positioning of the dividing wall effectively affects the separation efficiency and energy consumption, especially when the feed contains vapor phase. In the present paper, ternary mixture of benzene, toluene, and p-xylene is selected as the separation system to study the effect of the feed vapor fraction on the optimal positioning of the dividing wall in a DWC and proposes a method for determining the optimal position.By using rigorous simulation and the total annual cost(TAC) as the objective function, the economic performance of the DWC is investigated under different vapor fractions of the feed, and feed with vapor can save up to 23.33% of TAC compared to feed with liquid. The results demonstrate the importance of optimal dividing wall positioning when the feed contains vapor phase by sensitivity analysis.