(377f) Tri-Temperature Controlled Cyclic Total Reflux Batch Distillation without Reflux Drum

A novel operation mode, i.e. tri-temperature controlled cyclic total reflux batch distillation without reflux drum, is proposed and experimentally studied. Three temperatures, top, middle and bottom temperatures, are used to control the alternation of the states of total reflux and total withdrawal of the column and in result to keep the column run with the highest enrichment efficiency, the largest flow rate for product draining and no ?fly wheel effect?. In experiment the separation of binary mixture ethanol-propanol was carried out to verify the control strategy and the performance of self-developed tri-temperature control system. The results indicate that, compared with the constant reflux ratio operation mode and single column top temperature control method, the temperature and concentration at the column top can be controlled much more precisely and steadily. The product yield increases and the amount of slop cut decreases significantly with the same product specification.