一种改进的多元精馏塔动态模型

综合了精馏塔的物料及能量平衡、塔板水力学方程、塔板效率及再沸器动态特性,给出一种改进的非理想多元物系精馏塔通用动态数学模型.增加了汽液平衡计算,从而弥补了文献1]所提出的动态模型的缺陷,提高了其精度和通用性.模型仿真算法采用Gear积分方法,稳定性好,对解刚性比很高的精馏塔微分方程组十分有效.通过对某丙烯腈萃取精馏塔的仿真表明,该动态模型能够较好地反映对象的动态形为.

AN IMPROVED DYNAMIC MODEL OF MULTICOMPONENT DISTILLATION COLUMN

An improved dynamic model of nonideal multicomponent distillation column is presented in this paper, in which the simultaneous effects of mass and heat transfer, tray hydraulics, tray efficiency and reboiler dynamics are taken into account. It overcomes the shortcomings of the model derived in a previous paper1], by adding vapor-liquid equilibrium bubble-point calculation. Therefore, higher accuracy and greater usefulness of the model have been achieved. It can be used to simulate the distillation column which separates either an ideal system or a highly nonideal system. The Gear's procedure is adopted as a simulation method for its stable property. It is very effective for solving the differential equations with high stiffness ratio. An acrylonitrile extractive distillation column is taken as an example to verify the model given here. The model can really represent the actual dynamics of the distillation column.