Calculation of Cogeneration Potential of Total Site Utility Systems with Commercial Simulator

Abstract

Cogeneration potential of utility systems is one of the important indicators for the design of Total Site utility systems. In this paper, a new method is proposed to calculate cogeneration potential of Total Site utility systems. The temperatures of steam mains are calculated with Aspen Plus simulator first. Steam flow rates are calculated based on temperatures of steam mains and head loads of process, then. Based on the temperatures and steam flow rates obtained, shaft powers generated by the steam turbines in expansion zones can be obtained with the built-in block COMPR in Aspen Plus simulator. Compared to the existing methods, the method proposed needs not complex calculation procedure. For the illustrated case studies, the results obtained by this method are comparable to that obtained in the literature. It is shown that the calculation procedure proposed in this paper is simple, and the results are accurate.