Radhika et al. , presented a vapor recompression scheme for the separation of a ternary zeotropic mixture of alcohols, where driving force (temperature difference) is maintained by a variable speed compressor with an estimated compression ratio. For the open loop operation with a single stage (one compressor), they perceived: that throughout 30% of the operation reflux flowrate profile shows almost constant at the maximum value, then it dropped almost 67%, afterward is instantaneously rose for more than 30%, and, keeping constant for the next one-tenth of the time, then almost linearly dropped to the same value previously achieved and keeping constant till the end of the process. Also, it requires more than twenty compression ratios to compress the vapor completely, whereas, for double-stage operation compression ratio is divided equally for both the compressors, however, it brings only 1.20% in energy savings compared to single-stage. Rihm et al. , used the first principle model, ie. Radfrac column of ten stages with a full set of mass and energy balances, along with pressure driven model, to show that if not enough data from the real plant is available, high-accuracy process simulators can be used to parametrize data-based models. Niazi et al. , showed that for dehydration of methyl isobutyl ketone, simple distillation unit operation with no reflux is better to use than the batch distillation unit with a decanter: if the total return fraction (methyl isobutyl ketone and water) higher than 0.7, then it is proven to give both, better energy efficiency and production rate. On the other side, Niazi et al. , compared an inverted batch distillation unit with a decanter to a conventional batch distillation unit, to conclude that it achieves 7%/9%/17%, resp., in fractional recovery/time reduction/energy savings, resp., for reason of gradual feeding that provides shorter pre-heating step, and, top feeding that assumes direct contact between vapor and liquid phases.