考虑间壁换热的间壁塔模型的模拟仿真研究

精馏是化工生产过程中应用最广泛的分离技术。间壁塔作为一个完全热耦合精馏塔,与传统两塔精馏序列相比,不仅可以减少设备投资,减少占地面积,还能节约精馏过程中的能耗。以环己烷-环庚烷-环辛烷的分离为研究对象,建立间壁塔和传统两精馏序列的模型,分析间壁塔的间壁传热对总能耗的影响,对新工艺(间壁塔分离工艺)和旧工艺(传统两塔精馏序列分离工艺)进行仿真和优化研究。通过优化计算,在满足产品纯度要求前提下,得到了两工艺的最优工艺操作条件。比较两种工艺的塔板数和能耗,间壁塔工艺在节约成本的同时节能17.9%。

Study on Dividing Wall Column Simulation with Heat Transfer Across its Divided Wall

Distillation is the most widely used separation technology in chemical production processes.As a fully thermally coupled rectification column,the dividing wall column(DWC)not only reduces equipment investment and floor space,but also saves energy consumption during rectification compared with traditional two columns distillation sequence.In this paper,the separation of cyclohexane-cycloheptane-cyclooctane was studied.The model of DWC and two columns distillation sequence was established.Considering the influence of the partition wall heat transfer on the total energy consumption of the dividing wall column,simulation and optimization calculations were carried out for the new process(DWC process)and the old process(traditional two columns distillation sequence).Through optimization calculation,the optimal process operating conditions of the two processes were obtained under the requirements of product purity.Comparision of the number of stages and energy consumption of the two processes shows that the dividing wall column not only saves cost but also saves energy by 17.9%.