关键词: 间歇精馏, 全回流, 全采出, 无累积罐循环全回流, 三温控

Abstract: A control method of total reflux by introducing temperatures of top part，upper-middle part and middle part in batch distillation column without reflux drum was proposed. The ethanol—n-propanol system identified as a typical ideal system was used to conduct the experimental study of this operation. The optimized temperature control conditions were determined by experiments：when the temperature of the top part was stable and difference between the upper-middle part and the top part was 0.3 ℃，the total reflux operation would be switched to the total withdrawal operation，and if the temperature of the middle part rose by 1 ℃，the total withdrawal operation should be converted to the total reflux operation. From the results of experiments under the same operating conditions，the influence of different feed concentrations on the overhead product average purity is not significant，basically maintained at 0.99（mass fraction）. Finally，compared with dual temperature control method under the same feed concentration and operating conditions，this tri-temperature control method reduces operating time by 23.3 min，promotes separation efficiency by 23.95%，increases the purity of product by 1.06% and increases the product yield by 1.08%.

Key words: batch distillation, total reflux, total withdrawal, cyclic total reflux operation without reflux drum, tri-temperature control