Study On The New Operation Method And Simulation Of Batch Distillation

Cyclic total reflux operation is one of the new operating modes of batch distillation. It involves three periods: total reflux, dumping and filling up. Cyclic total reflux operation has several advantages over conventional operation with high efficiency, energy saving and convenient controlling. It was proposed in the 1960's and developed rapidly in the 1990's. However, some theory problems, for example, the fluid dynamics and mass transfer during the filling up period which could not be dealt with in conventional distillation theories has been remained unstudied.The models for cyclic total reflux operation were established in this paper. A controlling method of total reflux by introducing temperatures of middle part and top part in batch distillation column, and Isopropyl alcohol and n-propyl alcohol was used to conduct the experimental study of this operation. The result indicates that the state switch of total reflux and total withdraw by controlling double-temperature in cyclic total reflux operation process is completely feasible. Furthermore, introducing the controlling point of middle part temperature in column makes the quantity and quality of production better than that of the method only using top part temperature, and it makes controlling operation flexibility more high, but switching times of the new method are more than the old one.The viability of controlling the transitional fraction sect of cyclic total reflux operation by time impulse was demonstrated by experiments too. Thus, the operation become more successive and compact, and the automatic control of cyclic total reflux operation batch distillation was made easy. Experimental results were in good agreement with simulation results.