Acetone refining processes are usually high in energy cost since the acetone purity and recovery rate should meet the product specification simultaneously. Different heat integration approaches are applied in a typical acetone refining process, which produce high-purity acetone product from crude acetone. The processes with energy-saving approaches are optimized according to total annual cost (TAC), and the TAC calculation results are compared to identify the energy-saving effects in the acetone refining process. Optimization is also applied for processes with different acetone product purity specifications to distinguish the influence of purity specification on final optimization results. The results showed that the heat integration can achieve a decrease of 30% on energy consumption and 17% on TAC, and the selection of product purity specification level also have an influence on energy cost and TAC. This indicated that the producers can vary their acetone product specification to obtain a large decrease of energy consumption according to their product purity demand, and it is also possible to use other separation methods with less energy cost in the treatment of acetone product with lower purity to improve the product purity, such as membrane separation.
Keywords acetone, heat integration, separation, energy-saving, thermodynamic efficiency, CO2 emission