Comparative analysis of liquid mixture separation flowsheets

Objectives. When developing separation flowsheets for liquid mixtures, preference is often given to a specific process or flowsheet. Although alternative separation variants are sometimes considered, these tend to be based on a single-phase process, usually distillation. And while review papers on the specifics of implementing a particular separation technique exist, these mainly focus on the specific process of extractive distillation, combination of distillation and splitting processes, and extraction. Moreover, studies comparing the separation flowsheets of mixtures of different physicochemical nature based on different processes and special methods are fragmentary. This study presents a comparative analysis of the processes and methods of liquid mixtures separation based on a critical review of the literature and the authors’ own research results.

Methods. The study is based on the critical analysis of literature and mathematical modeling of phase equilibria using local composition equations via freely distributed software packages.

Results. Specific liquid mixture separation methods, including combining various processes in one flowsheet (including hybrid technologies), are compared in terms of their advantages and disadvantages.

Conclusions. Promising areas of further research in the field of synthesis of organic mixtures separation flowsheets through the use of various separation processes and methods are identified. The effectiveness of the various processes (extraction, splitting, special distillation techniques) is estimated at different stages of different number of components mixtures separation. A comparative analysis of extractive and heteroazeotropic distillation processes when separating mixtures of different initial composition highlights the areas of energy advantage of each process. The effectiveness of the flowsheets is estimated by combining extraction with other processes, depending on the stage of extractant regeneration.

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