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As an important solvent, acetone is widely used in many chemical, pharmaceutical and light industries. Recovery of acetone is very important for economy and environment of these industries. Presently, many industries, especially production of cellulose acetate, still use typical activated carbon adsorption-desorption-distillation technology for recovery of acetone. The technology is high energy consumption, and lack of process safety and stability. Saving-energy becomes the key topic for recovery of acetone. In this paper, based on the pre-research results of our group and literatures, the energy conservation of water absorption-distillation flowsheet is proposed and improved.During the water absorption-distillation flowsheet, dilute acetone solution is obtained after absorption, which results in high energy consumption in distillation. It’s found that additives have great effect on the absorption efficiency, thus, additives including surfactant, dispersant and salts were added in water for enhancement of acetone absorption. In this paper, bubbling water-layer is also investigated to enhance absorption.Then, Aspen Plus process simulation software is selected to analyze the distillation unit. The invariant zone is found existing in the actual process of acetone distillation column, it results in high construction cost and energy consumption. Thus, the invariant zone is removed by optimal design, and construction and control scheme of distillation column are also conducted in this paper.Finally, based on the above studies, the pilot-plant experiments are conducted, and the results are briefly summarized. The results show that the improved water absorption- distillation flowsheet is better than the authoritative reports, and show good performance of energy-saving.
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