Calculation of the Rectification Column Network for the Criterion of the Minimum Exergy Loss

Abstract

The existing methods of calculation of the heat and power systems are based on the superstructure model. As it is commonly known, the term superstructure means a very complicated system which undergo simplification to the real and uncomplicated structure. The simplification of superstructure is performed according to the formulated objective function, where the decisive variables are mixed: integer and real. The existence of integer variables makes the serious disadvantage for the industrial application of the method because it is very difficult to find the extreme of the objective function even for the very simple system. For the complicated industrial systems it is a very big achievement to prepare the superstructure. However, for this case the simplification of the superstructure and searching for the extreme of the objective function is practically impossible. Taking into account these obstacles, the author proposed the method of calculation of the rectification column network (RCN). The mathematical model is based on the idea of the ideal column model with multitude of reboilers and condensers. For this model the integer decisive variables doesn’t exist, thus it is possible to elaborate the reasonable results even for very complicated systems.