用夹紧区原理确定多元恒回流比分批精馏最小回流比  

DETERMINATION OF MINIMUM REFLUX RATIO FOR CONSTANT REFLUX OPERATION IN MULTICOMPONENT BATCH DISTILLATION

作　　者：张雪梅[1] 简春贵[2] 张卫江[1] 杨志才[1] 

机构地区：[1]天津大学化工学院,天津300072 [2]天津天大天久科技股份有限公司,天津300072

出　　处：《化工学报》2004年第9期1469-1473,共5页CIESC Journal

摘　　要：夹紧区是精馏塔内出现的浓度几乎不变的区域 ,对于三元物系来说 ,根据夹紧区在塔内出现的位置可分为 :上、中和下加紧区 .在无穷板数和任一瞬时釜浓下选择不同的回流比可使分批精馏处于不同夹紧区下操作 .文中讨论了三元恒回流比分批精馏过程中夹紧区的演变 ,在Rayleigh方程的基础上建立了应用夹紧区原理确定多元恒回流比分批精馏最小回流比的方法 .该方法并不要求相对挥发度为常数 ,并且能准确计算顶浓 ,克服了通常所采用的Underwood公式法的缺陷 ,为多元分批精馏的简捷设计奠定了基础 .The pinch zone in a distillation column is the stages where the liquid or vapor composition varies very little. It can be classified into upper, middle and lower pinch zones for ternary distillation according to the different locations of its occurrence. In batch distillation with an infinite number of stages, different pinch zones may appear under the same instantaneous bottom composition when the column is operated at different reflux ratios. In this paper, the development of pinch zone for ternary systems in constant reflux operation was discussed. The method of determining minimum reflux ratio for constant reflux operation in multicomponent batch distillation was presented on the basis of Rayleigh formula, which made the assumption of constant relative volatility unnecessary and could compute the distillate composition accurately. Thus, the method has overcome the shortcomings of Underwood formula, and provides a sound basis for short-cut design of multicomponent batch distillation column.

关 键 词：多元分批精馏 最小回流比 夹紧区 简捷设计 

分 类 号：TQ028[化学工程]