Pilot-scale studies of process intensification by cyclic distillation

Process intensification in distillation systems receives much attention with the aim of increasing both energy and separation efficiency. Several technologies have been investigated and developed, as for example: dividing-wall column, HiGee distillation, or internal heat-integrated distillation. Cyclic distillation is a different method based on separate phase movement-achievable with specific internals and a periodic operation mode-that leads to key advantages: increased column throughput, reduced energy requirements, and better separation performance. This article is the first to report the performance of a pilot-scale distillation column for ethanol-water separation, operated in a cyclic mode. A comparative study is made between a pilot-scale cyclic distillation column and an existing industrial beer column used to concentrate ethanol. Using specially designed trays that truly allow separate phase movement, the practical operation confirmed that 2.6 times fewer trays and energy savings of about 30% are possible as compared with classic distillation.