热集成变压精馏分离甲缩醛和甲醇工艺模拟及优化  

Simulation and optimization of heat-integrated pressure swing distillation for the separation of methylal and methanol

作　　者：杨金杯[1] 余美琼[1] 陈玉成[1] 陈文韬[1] 

机构地区：[1]福建师范大学福清分校生物与化学工程系,福建福州350300

出　　处：《计算机与应用化学》2013年第7期818-822,共5页Computers and Applied Chemistry

基　　金：福建省教育厅科研资助项目(JA12355)

摘　　要：在分析甲缩醛和甲醇二元体系共沸特性基础上,提出热集成变压精馏分离甲缩醛和甲醇共沸体系的工艺方法。利用AspenPlus软件对该分离过程进行模拟计算,采用NRTL方程作为物性计算模型,其二元交互作用参数由汽液相平衡数据回归,详细分析了加压塔和常压塔的理论板数、进料位置和回流比对分离过程的影响,并进行能耗比较。结果表明,采用热集成变压精馏分离工艺,可很好地实现甲缩醛与甲醇的分离,较佳的操作条件为:加压塔操作压力1.0MPa,理论板数28,第18块板进料,回流比3.2,塔釜甲缩醛含量可达99.9%;常压塔操作压力0.1 MPa,理论板数24,第14块板进料,回流比2.6,塔釜甲醇含量可达99.5%。与常规变压精馏相比较,热集成变压精馏可节省能耗达35.5%,为共沸物分离过程的设计和改造提供依据。Heat-integrated pressure swing distillation for separating a homogeneous azeotropic mixture composed of methylal and methanol was developed based on the dependency of the azeotropic composition on the system pressure. The Aspen Plus was used to simulate the separation process, using NRTL activity coefficient equation as the physical model, and the NRTL binary interaction parameters for methylal and methanol were correlated by experimental VLE data. The effect of theory stage, feed location and reflux ratio were detailed analyzed. The results shown that the methylal and methanol could be high efficiently separated by heat-integrated pressure swing distillation, the optimal condition： for high pressure tower, the pressure 1.0 MPa, theory plates 28, the 18th plate as feed plate, reflux ratio 3.2, and the purity of methylal of 99.9 % at the bottom of tower; for atmospheric pressure tower, the pressure 0.1 MPa, theory plates 24, the 14th plate as feed plate, reflux ratio 2.6, and the purity of methanol of 99.5 % at the bottom of tower. The heat-integrated pressure swing distillation could save energy consumption by 35.5 %, compared to the conventional pressure swing distillation, thus realizing a remarkable energy-saving. The results could be provided for the design and improvement of the separation of azcotropic system.

关 键 词：甲缩醛 甲醇 ASPEN PLUS 热集成 变压精馏 

分 类 号：TQ028[化学工程]