Advanced Distillation Technologies for Dimethyl Ether Production: A Comprehensive Techno-economic Evaluation

Abstract

Dimethyl ether is a promising alternative energy source to liquefied petroleum gas and diesel fuel due to its cleaner combustion properties. However, dimethyl ether production from methanol typically suffers from intense energy consumption, high CO₂ emissions, and large costs. Advanced distillation technologies, particularly reactive distillation (RD) and dividing-wall column (DWC), are potentially capable of addressing such issues. The present study evaluates the techno-economic performance of those advanced distillation technologies by accounting for a complete set of reaction and separation functions and an identical catalyst, i.e., Amberlyst-35, for each process configuration. The use of a common catalyst ensures that the identified performance differences are attributable to the technology configurations themselves rather than the variations in catalyst type. The finding interestingly suggests that the DWC scheme outperforms both conventional reactor-distillation and RD schemes. The specific energy consumptions for the conventional, RD and DWC schemes are 1.74, 4.10 and 1.41 GJ/ton, respectively, while the CO₂ emissions for those schemes are 0.09, 0.22 and 0.08 tons CO₂/ton, respectively. The DWC scheme offers the lowest total annual cost, i.e., $1,601,733/year, followed by the conventional and RD schemes, which are $1,844,407/year and $2,585,633/year, respectively.