【作者】 穆钰君；

【导师】 白鹏；

【作者基本信息】 天津大学 ， 制药工程， 2009， 硕士

【摘要】 循环全回流间歇精馏操作方法是近年来开发的间歇精馏新型操作方法之一。这种操作方法包括全回流浓缩和无回流采出两个基本操作状态,反复循环直到操作结束。同传统的间歇精馏过程相比,全回流操作方式能获得最高的浓缩速率,而全采出操作方式具有最大的排出速度,可在最短的时间内将轻组分从塔顶馏出,具有分离效率高、控制简便,对扰动不敏感,易于操作的优点。目前的研究基本上集中在操作方法的理论研究方面,而缺少对其优化控制的实验研究。本文针对已有控制方法的不足,提出了循环全回流间歇精馏的一种新型控制方法—多温控制法,并建立了实验装置,以乙醇-正丙醇为实验物系,对该控制方法进行了研究。首先对循环全回流间歇精馏过程的基础—全采出过程进行了实验研究和模拟研究,然后对循环全回流间歇精馏多温控制过程的具体控制方法进行了研究,考察了不同进料浓度、温度控制点和全采出时间下多温控制过程的规律;然后在上述研究的基础上,提出了循环全回流间歇精馏多温控制法;最后在相同的实验条件下对比了单温控制法、双温控制法和本文提出的多温控制法。实验结果表明:本文提出的多温控制法和单温控制法相比,操作时间仅增加了3%,而采出产品的体积增加了27.76%,轻组分回收率提高了19.63%;和双温控制相比,采出产品的总量和轻组分回收率降幅均不超过3.09%,而操作时间节省了35.88%;因此,和已有的单温和双温控制法相比,多温控制法可以在较短的时间内最大限度采出轻组分,同时有效防止重组分的上升,保证得到高浓度的合格产品,明显优于已有的单温控制法和双温控制法。更多还原

【Abstract】 Cyclic total reflux operation is one of the new operating modes of batch distillation. It involves two basic operation states: total reflux and total withdrawal and the alternation of them are carried out until the whole operation is completed. This operation is one of the most promising modes of batch distillation for its unique advantages over conventional partial reflux mode in highest enriching efficiency under total reflux and fastest product collection rate under total withdrawal, together with high efficiency, energy saving and convenient controlling. Few researches are focused on the development and optimization of the control method for this new operation mode which needs more precise and optimized control in order to give full play to its potential.To conquer the disadvantage of the former control methods, a novel control method of cyclic total reflux batch distillation without reflux drum, i.e., multi-temperature control was studied using ethanol-propanol as the experimental mixture. First, total withdrawal process was researched by experiment and simulation. Also, multi-temperature control process was explored at different feed concentrations, temperature control points and total withdrawal time. Then, multi-temperature control method was proposed accordingly. Finally, contrast experiments of single temperature control, dual-temperature control and multi-temperature control were carried out.The results showed that compared with single temperature control, the operation time increased by only 3%, while the volume and recovery of the light component increased by 27.76% and 19.63% respectively. And compared with dual-temperature control, the volume and recovery of the light component decreased by no more than 3.09%, while the operation time saved by 35.88%. So it can be seen that compared with single temperature control and dual-temperature control, more light component was collected in shorter time by multi-temperature control. At the same time, the heavy component was effectively kept in the lower part of the column and high concentration of the distillate is assured. Therefore, the novel multi-temperature control method holds obvious advantage over the other two control methods.更多还原