Abstract

The energy integration between a system composed by a natural gas pipeline distribution and a thermoelectric plant that needs to cool their water process is examined. The heat integration is formulated as an optimization problem, including the optimal heat exchanger network (HEN) design. The formulation is based on the isothermal mixing superstructure proposed by Yee and Grossmann and modified for multiperiod data by Papalexandri and Pistikopoulus. It is also based in the disjunctive formulation presented in the work of Sorzak and Kravanja, which accounts for different heat exchangers. The formulation can be summarized as the minimization of the annualized cost subject to heat balances, temperature specifications, and logical constraints that link the continuous with the binary variables, disjunctive equations using the convex-hull formulation for each heat exchanger units. Once the HEN is obtained, a NLP optimization is proposed to eliminate the isothermal mixing restriction. This is an abstract of a paper presented at the 7th European Congress of Chemical Engineering-7 and 19th International Congress of Chemical and Process Engineering CHISA (Prague, Czech Republic 8/28/2010-9/1/2010).