Butanone and ethyl acetate are widely used in chemical production and separation. They are usually used together in actual production. Therefore, it also appears in the waste water. Butanone and ethyl acetate will inevitably form three binary azeotropes with water, rendering their separation very difficult. In this study a butanone/water/ethyl acetate ternary azeotropic system is separated by an extractive distillation process. The extractant is screened by relative volatility and toxicity analysis. The optimal process parameters are obtained based on a genetic algorithm by minimizing annual total cost, achieving an efficient separation of the butanone/water/ethyl acetate ternary azeotropic system. Based on the thermodynamic analysis of the extractive distillation process, the separation process is improved and optimized to achieve a maximum utilization efficiency of energy. The annual total cost and pollutant emissions are studied and analyzed. The optimized extractive distillation process can significantly reduce the energy consumption and pollutant emissions, improve the thermodynamic efficiency and economy. The efficient and energy-saving extraction distillation process based on thermodynamic analysis provides a viable option towards an environmentally benign industry.