| This paper proposed and studied a new operation mode of batch stripping distillation—the stripping batch distillation with multi-reboiler. By heating the column with several reboilers located along the column at different height, this new mode can obviously shorten the operation time of batch stripping, and can effectively decrease the liquid hold-up at the bottom. The advantages of the new mode are very helpful in the separation of heat sensitive materials.In the paper, the experimental study investigated the stripping batch distillation with multi-reboiler. Two mixtures were used, they were 1-propanol-isopropanol and ethanol-acetic acid-acetic ether. The aim of using the 1-propanol-isopropanol was to testify the advantages of decentralized heating on the hold-up and operation time primarily. The ethanol-acetic acid mixture was used to prove the effectiveness of the new operation for separation of heat-sensitive materials. The decomposition rate of acetic ether was reduced by 9.54% with one reboiler in the middle, and reduced by 16.8% with two reboilers.The advantage of separating heat sensitive materials by the stripping batch distillation with multi-reboiler was discussed theoretically in this paper. The superiority of this method to ordinary distillation was verified through the calculating of equipment degradation index ID and the material decomposition ratio D .Take acetic acid for example, the results showed that compared with normal distillation, the equipment degradation index ID of stripping batch distillation with one reboiler was reduced by 3.84, the material decomposition ratio D was reduced by 13.02%; if with two reboiler, the ID was reduced by 3.96, D was reduced by 15.597%.The simulation and optimization of this method were also carried out in this paper. Three important parameters: the heat duty of the middle reboilers, the number of middle reboilers and the location of the middle reboilers were analyzed. The optimal parameters were found.
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