Heat process synthesis

Papoulias, S. A., and Grossmann, I. E., A Structural Optimization Approach in Process Synthesis II. Heat Recovery Networks, Computers Chem. Eng., 7 707, 1983. 

The task of process synthesis is to evaluate these schemes and select the best. The creative possibilities of design do not stop here. For example, these separations can be carried out by heat integration, by multiple-draw columns, or by use of processes other than distillation many other variations are possible. 

El-Halwagi, M. M. (1993). A process synthesis approach to the dilemma of simultaneous heat recovery, waste reduction and cost effectiveness. In Proceedings of the Third Cairo International Conference on Renewable Energy Sources ( A. I. El-Sharkawy and R. H. Kummler, eds.), Vol. 2, pp. 579-594. ... 

The template methods have also been used for the synthesis of a number of substituted Ln di(naphthalocyanine) complexes, LnNc2 [82-88]. Apart from thermal fusion by conventional heating processes, complexation has been initiated by microwave radiation, although only a few publications are devoted to the template synthesis of lanthanide bis(phthalocyanine) complexes by this method [89, 90]. The use of microwave radiation (MW) reduces the reaction time from several hours to several minutes. Unsubstituted complexes LnPc2 (Ln = Tb, Dy, Lu) were prepared [90] by irradiation (650-700 W) of a mixture of phthalonitrile with an appropriate lanthanide salt for 6-10 min (yields >70%). 

Process Synthesis, an important research area within chemical process design, has triggered during the last three decades a significant amount of academic research work and industrial interest. Extensive reviews exist for the process synthesis area as well as for special classes of problems (e.g., separation systems, heat recovery systems) and for particular approaches (e.g., insights-based approach, optimization approach) applied to process synthesis problems. These are summarized in the following ... 

Having described the overall process system, its three main interactive components (i.e., the chemical plant, the heat recovery system and the utility system), as well as the three subsystems of the chemical plant (i.e., the reactor system, the separation system, and the recycle system) we can now define the process synthesis problem. 

S. A. Papoulias and I. E. Grossmann. A structural optimization approach in process synthesis - II. Heat recovery networks. Comp. Chem. Eng., 7 707,1983. 

Nicol W, Hemier M, Hildebrandt D, Glasser D. The attainable region and process synthesis reaction systems with external cooling and heating. Chem Eng Sci 2001 56 173-191. 

Early work in process synthesis focused on the solution of specific problems, such as the best sequence of distillation columns to perform separation of components in feedstreams into product streams. Another early problem was the synthesis of heat-exchanger networks. 

Synthesis is the step in design where one conjectures the building blocks and their interconnection to create a structure which can meet stated design requirements. This review paper first defines chemical process synthesis and indicates the nature of the research problems—to find representations, evaluation functions and search strategies for a potentially nearly infinite problem. It then discusses synthesis research and the most significant results in each of six areas—heat exchanger networks, separation systems, separation systems with heat integration, reaction paths, total flowsheets and control systems. 

We should mention that the modern process-synthesis methods can ensure intrinsically the optimization of subsystems, such as reactions, separations and heat exchange. Therefore, by searching in the first stage the structural optimization of the flowsheet and by performing later the optimization of units should lead quite soon to the true overall optimum in a large number of situations. 

The topic of synthesis will be be covered in the following paper by Douglas [ 1 ]. I myself have recently written two papers, each in part a review of process synthesis [2, 3]. Several articles have reviewed synthesis in the last decade, one over 40 journal pages long. The brief summary in this paper will be limited to a few ideas that are not usually discussed but that are thought to be important in process synthesis when heat effects do not dominate the decision making. A more extensive section on analysis completes this work. The paper by Morari [4] will present ideas on plant operation and control. 

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