A new mixed integer linear programming (MILP) model suitable for optimizing scheduling problems typical in chemical and related industries is developed. These problems have characteristics like storage time constraints, operational connectivity restrictions, and continuous tasks with special precedence constraints. Therefore, a new MILP model is developed for handling these special scheduling problems. The numerical capability of the model is demonstrated using test problems of different complexity levels.

A new, R-graph based, superstructure and corresponding MINLP model for designing conventional distillation columns are presented. A GDP representation (GR) of the superstructure is first constructed, then it is transformed to MINLP representation to which, in turn, additional trivial improvements are added. The new model has been tested on binary mixture examples, and the obtained results are compared to the results of an MINLP model which developed according to the GDP model of Yeomans and Grossmann. 9 The new model yields shorter computation time and provides better local optima. Additionally, the new model has been used for optimizing a complex multicomponent separation system consisting of several distillation columns. In order to handle such a complex system with a huge number of nonlinear equations, the outer approximation algorithm is modified to provide good initial values for the NLP subproblems.

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Extractive distillation processes are investigated by optimization. The proposed MINLP model and optimization tool are able to analyze complex distillation processes. Application of the method is demonstrated on two different extractive processes: acetone/methanol mixture using water as heavy solvent and ethanol/water mixture using methanol as light solvent. The two systems are analyzed separately; the analysis is performed both from technological and economical aspects. The optimal structures are found widely independent of the weights of different cost parts. Thus, small changes in the economic environment will not alter the optimal configuration.

Hydrogenated naphthalene derivatives Q 1010 Convenient Synthesis of 7,8-Dimethoxytetralin-2-one. -An efficient method to synthesize the title compound (XII) using simple reaction steps and commercially available starting materials and reagents is presented. -(GORKA, A.; CZUCZAI, B.; SZOLECZKY, P.; HAZAI, L.; SZANTAY*, C. J.; HADA, V.; SZANTAY, C.; Synth.