화학공학소재연구정보센터
Industrial & Engineering Chemistry Research, Vol.59, No.51, 22247-22257, 2020
Simultaneous Optimization of a Heat-Integrated Coal-to-SNG/MeOH Polygeneration Process Based on Rigorous Kinetic Models
In this article, a novel simulation-optimization method is proposed for the simultaneous design of a heat-integrated coal-to-SNG/MeOH (CTSM) polygeneration process, aiming at exergy efficiency enhancement. The genetic algorithm is adopted to simultaneously optimize the presented polygeneration process, which combines the key reaction units based on rigorous kinetic modeling and simulation with a waste heat recovery steam cycle (WHRSC). A heat integration approach that considers variable stream conditions is introduced to connect CTSM and WHRSC. In developing this approach, an extended Duran-Grossmann (D-G) model is established, which incorporates the isothermal phase change and nonisothermal phase change. The interaction mechanism between process synthesis and heat integration is further explored. Compared with the base case obtained by a sequential method, the presented method yields a 2.22 percentage point increase in the overall exergy efficiency and a 44.05% improvement of power generation. In this sense, the utility consumption in the polygeneration process can be sharply reduced and even achieve zero hot utility consumption. The corresponding heat exchanger network is determined that consists of 56 heat exchangers and 7 coolers with a total area of 93 763 m(2). Furthermore, the interaction among different process units reveals that process synthesis has a stronger effect on heat integration.