Energy efficient extractive distillation process assisted with heat pump and heat integration to separate acetonitrile/1,4-dioxane/water.

Two energy efficient extractive distillation processes are proposed to separate acetonitrile/1,4-dioxane/water mixture in this study. The COSMO-SAC model is chosen to screen suitable entrainer and dimethyl sulfoxide is selected. Process intensification technologies of heat pumps and heat integration are utilized in the processes for energy conservation. Several evaluation methods containing energy, economic, environmental and exergetic analysis are introduced to evaluate the performance of different processes. The most energy-saving and environmental friendly process is heat pump assisted direct extractive distillation that achieves an energy reduction by 53.58% and a carbon dioxide emission reduction by 53.56% compared to the indirect scheme, while the direct scheme assisted with heat integration performs best that achieves a reduction by 40.38% on total annual cost. [ABSTRACT FROM AUTHOR]