An approach to obtain Heat Integration scheme with higher viability for complex system

Focused on the problem of low viability of Heat Integration (HI) scheme for complex system, a strategy and a method of hierarchical Heat Integration (HHI) were proposed in this paper. The practical limitations and energy target were combined stage by stage to determine the number of hierarchy and the optimal HI scheme in HHI method. The coproduction system, which can produce the syngas, semicoke and light oil, was selected as the study case. Based on the proposed method, HI of coproduction system was performed from different hierarchies. During the partition of coproduction system, the practical limitations were considered stage by stage, and HI of that system was investigated from different hierarchies. The optimal HHI scheme with higher viability and its energy saving ratio were achieved. The case study indicates that HHI method can work better for the HI complex system. The interior energy saving potential of complex system is revealed accurately by HHI, and the technical viability can be assured in the late implementation process of HI scheme.