甲醇四塔精馏系统的多目标优化

Multi-Objective Optimization of Four-Column Methanol Distillation System

粗甲醇的精馏是甲醇生产中的高耗能、低能效环节,而变负荷四塔精馏系统具有非线性、强耦合、强时延的特点,针对该系统的能耗优化既是生产成本控制和节能减排的重点也是难点。研究当进料负荷、进料质量、出料要求等条件改变时,如何调节系统的控制参数,以达到产品单位能耗和产量多目标的协同优化。实验结果表明单目标优化的单位能耗降低很多,但牺牲了产量;多目标优化的能耗优化效果略逊于单目标,但稳定地提高了产量。

Distillation process is the unit with high energy consumption and low efficiency for methanol production. Load changeable four column distillation system has the characteristics of non-linearity, strong coupling and time delay, and energy consumption optimization on this system is the key and difficult point for production cost control, energy saving and waste reduction. How to adjust system control parameter to meet multi-objective synergetic optimization for product unit energy consumption and productivity with change of feeding load, feeding quality and discharge requirement is studied. Experimental results show that single- objective optimization of the proposed algorithm reduces unit energy consumption sharply with productivity loss. Multi-objective optimization reduces less unit energy consumption with productivity stably increasing.