Thermodynamics process synthesis

The performance criteria are multiple ranging from economic to thermodynamic to operability considerations. As a result, the process synthesis problem can be classified mathematically as a... 

Process synthesis and design of these non-conventional distillation processes proceed in two steps. The first step—process synthesis—is the selection of one or more candidate entrainers along with the computation of thermodynamic properties like residue curve maps that help assess many column features such as the adequate column configuration and the corresponding product cuts sequence. The second step—process design—involves the search for optimal values of batch distillation parameters such as the entrainer amount, reflux ratio, boiler duty and number of stages. The complexity of the second step depends on the solutions obtained at the previous level, because efficiency in azeotropic and extractive distillation is largely determined by the mixture thermodynamic properties that are closely linked to the nature of the entrainer. Hence, we have established a complete set of rules for the selection of feasible entrainers for the separation of non ideal mixtures... 

Azeotropic distillation deals with the separation of mixtures involving one or several azeotropes. This problem, which in the past was tackled by means of experience and intuition, is today approached by means of systematic methods based on a deeper thermodynamic analysis. Here, we review the indispensable aspects for process synthesis. More details can be found in recent specialized books [8, 14]. 

The phenomena-driven method for the process synthesis analyzes not the processing units, the so-called building blocks, but the phenomena that occur in those blocks. This method is based on opportunistic task identification and integration. It was applied to separation process synthesis, based on thermodynamic phenomena. It explored the relationship between the physicochemical properties, separation techniques, and conditions of operation. The number of alternatives for each separation task is reduced by systematically analyzing these relationships. Then, possible flowsheets are produced with a list of alternatives for the separation tasks. 

This book aims is to treat the most important conceptual aspects of Process Design and Simulation in a unified frame of principles, techniques and tools. Accordingly, the material is organised in five sections. Process Simulation, Thermodynamic Methods, Process Synthesis, Process Integration, Design Project, and covered in 17 Chapters. Numerous examples illustrate both theoretical concepts and design issues. The work refers also to the newest scientific developments in the field of Computer Aided Process Engineering. 

Industrial enzymes are usually hydrolases that catalyse hydrolysis or synthesis reactions in aqueous environments. For thermodynamically controlled hydrolysis reactions, the equilibria can - in principle - be shifted completely to the product-side by dilution (increasing entropy of product formation). Thermodynamically controlled synthesis reactions using the reverse action of hydrolases can be enhanced by using excess of the cheaper reactants. This does not lead to compact processes, and affects their economic feasibiUty in a negative maimer. Therefore, possibilities to selectively remove reaction products from each other or fi om the reactors during the reaction are very attractive. 

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