Study of Different Types of Distillation Column for the Production of Methyl-Tert-Butyl-Ether

Description

Distillation is one of the most important separation processes due to the complexity involved, the energy required and vast applicability in chemical industries. Over the years a number of new technologies have been evolved so as to optimize the distillation process. Divided wall distillation column (DWC) and Reactive distillation column (RDC) are two such technologies which have brought about a drastic change not only in the production quantity and quality but has also improved the energy efficiency, cost redundancy and thus has proven to be an all-round feasible technology especially in petroleum petrochemical and pharmaceutical industries. The recent development of simulation technologies is one of the main reason that these distillation technologies evolved and got utilized in industries so effectively. ASPEN plus is one such modelling and simulation package that is used for optimizing any unit operation or process.

In this book, use of ASPEN plus to optimize the production of Methyl-Tert-butyl- Ether (MTBE) which is used in the gasoline to raise its octane number and is used as an oxygenate, using a conventional, DWC and RDC technologies has been described. Simulations were run for different reflux ratio, feed location, number of stages, operating pressures and temperatures and the process was optimized for each of the three columns. The study led to the conclusion that the production of MTBE was found to be the best in DWC and also the amount of energy required for the reboiler for heating was much less for DWC which was -40 mmkcal/h while in case of RDC and conventional column it was -44 and -47 mmkcal/h at the stage number of 45. The purity of the product was best seen in the DWC column which was found to be 98% and also the number of stages required was less as compared to the RDC and the conventional column. The heat load on reboiler was 2300000 kW in case of DWC column which was less as compared the other two. Thus DWC is more efficient in terms of energy consumption and require less number of stages and this leads to reduced operating costs and higher product quality. The rate of the production of the MTBE was 600 kmol/h in the DWC column and was highest as compared to the RDC and the conventional distillation column. There is no need of extra distillation column in the DWC as in conventional distillation column and this leads to lesser heat required in the reboiler.