基于塔板组成线的多组分精馏设计方法研究

介绍了精馏过程图解法设计的基本概念,根据塔板组成线的定义,推导出了塔板组成线的基本方程并给出了便于图解设计的塔板组成线作图规则.在研究塔板组成线性质的基础上,提出了可在不给定回流比和再沸比的条件下,同时获得多组可行设计方案的塔板组成线精馏设计策略.首先通过选择设计变量确定产品组成,由产品操作叶判断塔设计的可行性;然后对操作叶重叠的产品组成作塔板组成线图,找到多组可行设计方案;最后针对不同的目标,对众多方案进行筛选,找到最佳的设计和操作参数,从而完成精馏塔的设计.对理想和非理想物系进行的实例研究结果表明,由塔板组成线设计法得到的计算结果优于Fenske-Underwood简捷法,与Aspen plus的模拟结果吻合较好.

Studies on Multicomponent Distillation Design Method Using Stage Composition Lines

The design strategies for multicomponent distillation using stage composition lines were proposed. Also the design equations and the map construction rules for the stage composition lines were presented. As every intersection of a pair of rectifying and stripping stage composition lines represents a feasible distillation column design and from which the detail scheme of column design can be achieved, the method based on stage composition lines is better than the common approaches in terms of both accuracy and efficiency. By the strategies proposed, the design variables are specified at first to determine the product compositions, and the operation leafs of the products are used to estimate the feasibility of the distillation column designs. Then the stage composition lines for specified product, whose operation leafs overlappe each other, are drawn to get the multiple feasible designs, and finally the optimum design can be evaluated from those feasible designs. The design strategies proposed were applied to design the distillation column for ideal and non-ideal multicomponent systems and the result shows that the stage composition lines method is better than Fenske-Underwood shortcut method and conforms to the simulation results of Aspen plus.