摘要
利用Aspen Plus软件对碳酸二甲酯-甲醇物系,提出了热集成变压精馏新工艺,以年度总费用(TAC)最小为目标函数进行经济优化,优化结果显示可以节约能耗33.82%,TAC节省25.97%。在动态控制系统中,针对常压塔温度分布均匀、灵敏板选择困难的问题,给出一种简单有效的导斜率判据方法。在此基础上,研究了常压塔不同灵敏板以及不同控制结构对完全热集成工艺动态可控性的影响。结果表明:常压塔第29块塔板作为灵敏板的组成/温度串级控制结构CSC,可以有效处理±10%进料流量和进料组成扰动。对于超过10%进料流量和组成扰动,高压塔(HPC)压力波动大、产品不易控制的特点,在CSC基础上建立的压力-补偿温度控制结构CSD,使两塔产品的稳态余差较小,可以处理±20%的进料流量和组成扰动,实现更稳健的动态控制。
The full heat-integrated pressure swing distillation scheme for separation dimethyl carbonate and methanol system was proposed by means of commercial software Aspen Plus. The optimum design was obtained via taking the minimization of the total annual cost（ TAC） as an objective function,compared with the corresponding traditional heat-integrated pressure swing distillation process,with 33. 82% saving in energy consumption and 25. 97%reduction in total annual cost. During the dynamic control system,aiming at the problems of choosing the suitable sensitive plate caused by the uniform temperature distribution of the atmospheric column,a simple and effective scheme was put forward. The influences of the selection of the sensitive stage and dynamic control structure in the atmospheric column on the dynamic responses in the heat-integrated process were further studied on the base of rigorous steady-state simulation. The results show that the composition / temperature cascade control structure（ CSC） with stage 29 in the atmospheric column as the control stage can handle the ± 10% disturbances of feed flow rate and feed composition more effectively. The pressure-compensate temperature control structure（ CSD） was adopted to conquer the high pressure fluctuation and the unstable quality of the DMC product in the HPC because of exceeding ± 10% disturbances of feed flow rate and feed composition. Furthermore,the dynamic controllability was evidently improved; it can maintain the quality of the two products and deal with the ± 20% disturbances of feed flow rate and feed composition.
作者
张青瑞
彭家瑶
张凯
ZHANG Qing-rui PENG Jia-yao ZHANG Kai(College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042, Shandong Province, Chin)
出处
《化学工程》
CAS
CSCD
北大核心
2017年第1期60-65,共6页
Chemical Engineering(China)
基金
山东省自然科学基金项目(ZR2013BM001)
关键词
碳酸二甲酯
甲醇
TAC
热集成
动态控制
dimethyl carbonate
methanol
TAC
heat-integrated
dynamic control
