为深入研究差压热耦合精馏的节能特性,进而得到节能效果更佳的改进差压热耦合精馏流程,引入中间冷却器,提出了一种改进的差压热耦合精馏流程。以甲基环戊烷/苯二元物系为例,以标准煤能耗计算为基准,对改进前后2种流程的节能效果进行比较,考察了中间冷却器负荷变化对其热耦合程度的影响,以及进料温度对改进流程能耗的影响;通过对差压热耦合工艺系统分析,建立了差压热耦合精馏的一般通用模型,系统地考察了差压热耦合精馏3种典型的操作状态。结果表明,相对于原差压热耦合精馏流程,改进的差压热耦合精馏流程的节能效率达3.50%,并得到了两塔热量完全耦合时的中间冷却器负荷。
In order to more deeply study the pressure swing thermally coupled distillation (PSTCD) and achieve a more energy-consuming process, the improvement and optimization of PSTCD were conducted by adding a middle cooler, thus an improved PSTCD process was proposed. Taking methyl-cyclopentane/benzene binary mixture as an example, feed conditions and products specifications were set up. On the basis of steady simulation of the two processes and standard coal equivalent (ce), the characteristics of the improved PSTCD were compared with that of the conventional. Heat balance calculation and further analysis of improved PSTCD was conducted, and the sensitivity analysis of middle cooler duty was studied. Meanwhile, the effects of feed temperature on energy consumption were analyzed. In addition, a general PSTCD process was proposed to describe the process systematically, by which three typical operation states of PSTCD were acquired on the basis of different middle cooler duties. The conclusions were that the improved PSTCD had an energy saving efficiency of 3.50%, and had better performance than conventional PSTCD in energy saving. The duty of middle cooler was obtained when fully thermal coupling.