分批蒸馏优化策略与微机控制的研究(Ⅰ)——分批蒸馏的优化策略

本文提出了塔顶累积全回流及变压强综合回流两个分批蒸馏的新操作策略及相应的优化操作法,通过数学模拟和θ收敛计算法求出了二元(乙醇—异丙醇)和多元(正庚烷—正辛烷—正壬烷—正癸烷)物系的数值解.计算结果表明,两种新操作法分别较传统的操作法缩短生产周期30%和50%以上.

Study on Optimal Strategies and Microcomputer Control of Batch Distillation ( I )Optimal Operating Strategies

Two novel strategies and their optimized operating modes of batch distillation, i. e. top accumulation under total reflux and varying pressure under combined reflux, are proposed. For the first strategy, the product component is concentrated and collected in a large reflux drum under the condition of total reflux. For the second strategy, the column pressure is varied during operation in order to keep the column temperature below the thermal decomposition point of the residue in reboiler, and a combined reflux is used. The corresponding mathematical models which take into account the holdups in both condenser and column are proposed and solved by using (?) convergency method. The application of these new strategies to the separation of a binary mixture ethanol-isopropanol and a multicomponent mixture n-heptane-n-octane-n-nonane-n-decane show that the present proposals can shorten the operating period by more than 30% and 50% respectively in comparison with the conventional constant reflux operation.