近沸点及特殊宽沸点二元物系的热泵精馏分离工艺与控制方案

发布时间：2018-06-08 01:57

本文选题：近沸点 + 宽沸点　；参考：《青岛科技大学》2017年硕士论文

【摘要】：本文分别以近沸点物系正丁醇-异丁醇及特殊宽沸点物系异丙醇-氯苯为例研究了塔顶蒸汽再压缩型热泵精馏工艺及分割式热泵精馏工艺,采用以年度总费用(TAC)最小为目标函数的优化方法,确定工艺的最优操作参数;通过对不同工艺动态特性的分析确定了抗扰动能力强的控制方案。对于近沸点二元物系正丁醇-异丁醇,考察了塔顶蒸汽再压缩型热泵精馏及变压精馏热集成工艺的动态可控性。塔顶蒸汽再压缩型热泵精馏工艺,采用温度控制,研究发现精馏塔存在两个温度斜率峰值,选择不同温度控制板对控制系统的动态性能具有重要影响;变压精馏热集成工艺,采用双组分控制,组成-回流比串级控制结构可以实现稳健控制。两种分离工艺的最终动态方案对比结果表明:塔顶蒸汽再压缩型热泵精馏工艺采用简单的控制结构就可以取得较好的控制效果。对于特殊宽沸点二元物系异丙醇-氯苯,考察了上下塔的分离点浓度对分割式热泵精馏稳态工艺的经济性影响并首次提出了其工艺的动态控制策略。传统单塔精馏工艺、传统热泵精馏工艺以及分割式热泵精馏工艺的经济性优化结果表明:相较于传统单塔精馏工艺及传统热泵精馏工艺,分割式热泵精馏工艺的TAC分别减少34.06%、32.04%。对分割式热泵精馏分离异丙醇-氯苯工艺提出了不同的动态控制方案,结果表明改进的QRe/F与Wm/F控制结构对控制自由度减少的分割式热泵精馏工艺具有优势。本文研究了热泵精馏分离正丁醇-异丁醇、异丙醇-氯苯二元物系的方法及动态控制策略,对类似近沸点及宽沸点体系的稳态工艺优化及动态性能研究具有一定的参考价值。
[Abstract]:Taking n-butanol-isobutanol near boiling point system and isopropyl alcohol-chlorobenzene as examples, the distillation process of steam recompression heat pump and fractionated heat pump rectification process were studied in this paper. The optimal operation parameters of the process are determined by the optimization method with the minimum annual total cost as the objective function, and the control scheme with strong anti-disturbance ability is determined by analyzing the dynamic characteristics of different processes. For the near boiling point binary system of n-butanol-isobutanol, the dynamic controllability of the heat integration process of the top steam recompression heat pump and variable pressure distillation was investigated. By using temperature control, it is found that there are two temperature slope peaks in distillation tower. The selection of different temperature control plates has an important effect on the dynamic performance of the control system. Using two-component control, the structure of composition-reflux ratio cascade control can be used to realize robust control. The comparison of the final dynamic schemes of the two separation processes shows that the tower top steam recompression heat pump distillation process can obtain better control effect by adopting simple control structure. For a special wide boiling point binary system of isopropanol-chlorobenzene, the effect of separation point concentration of upper and lower column on the steady state process of fractionated heat pump distillation was investigated, and the dynamic control strategy of the process was proposed for the first time. The results of economic optimization of traditional single tower distillation process, traditional heat pump distillation process and split heat pump rectification process show that compared with traditional single column distillation process and traditional heat pump rectification process, the TAC of split heat pump distillation process is 34.06 and 32.04 less than that of traditional single column distillation process and traditional heat pump rectification process respectively. Different dynamic control schemes for separation of isopropanol and chlorobenzene by fractionated heat pump distillation are proposed. The results show that the improved QReR / F and Wm / F control structures have advantages in controlling the fractionated heat pump distillation process with reduced degrees of freedom. In this paper, the separation method and dynamic control strategy of binary system of n-butanol-isobutanol, isopropanol-chlorobenzene by heat pump distillation are studied, which has certain reference value for the steady state process optimization and dynamic performance study of similar systems with near boiling point and wide boiling point.
【学位授予单位】：青岛科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ028.31

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