Minimum Energy and Entropy Requirements in Multicomponent Distillation
نویسنده
چکیده
We present new analytical expressions for minimum energy consumption (1 law) and minimum entropy production, or lost work (2 law), in complex distillation arrangements. These simple, but exact, expressions apply to ideal mixtures and an infinite number of stages, and the relative volatility is the only required component property. The simple Vmin-diagram is shown to be very useful in evaluating minimum energy in alternative arrangements, including the use of double-effect (dual pressure) heat-integrated schemes. To illustrate the usage we use a ternary separation problem as an example and compare a set of various distillation arrangements. The numerical results in the example are interesting, but the main point is the simple way of obtaining them. The presented equations and methods are not limited to ternary mixtures and can be used for general multicomponent separation tasks. The reversible Petlyuk arrangement has zero lost work, but its total required heat supply is higher than for the typical (adiabatic) Petlyuk arrangements. However, there is a potential for further reduction by use of internal heat integration. This principle can also be applied to general heat-integrated arrangements (not only reversible). We also conjecture that the generalized adiabatic Petlyuk arrangement requires less energy than any other adiabatic arrangement at constant pressure when we consider configurations without internal heat integration.
منابع مشابه
Integrated Column Designs for Minimum Energy and Entropy Requirements in Multicomponent Distillation
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