Chemical reactors energy integration through virtual heat exchangers—benefits and drawbacks

The pinch analysis (PA) concept’s main drawback is that it is suboptimal since it disregards the chemical reactors network (CRN) contribution to the total flowsheet entropy generation, as it does with the separation trains, if any. The chemical reactors energy integration (CREI) through virtual heat exchangers (VHE) emerged and became, during its crystallisation period, an expansion of the classical PA, allowing the CRN to be seen as part of the heat exchangers network (HEN), perhaps leading to a better decrease in the total entropy production both through the inclusion of CRN sources and sinks into the HEN topology, and the improvement of the reactors operating conditions, while preserving their performance, in terms of chemical transformation. Throughout the considered case study, two-bed methanol synthesis heat integrated reactor, the benefits and the drawbacks of the CREI will be emphasized.