However, sequential optimization of unit operations and heat pump networks can lead to markedly sub-optimal solutions. For instance, optimizing parameters such as conversion rates in reactors, the recovery of components during separation processes, or the pressures of unit operations can be crucial for fostering effective heat pumping, thereby reducing emissions. Most prior formulations neglect variations in stream composition and pressure by altering operating conditions, limiting effective integration of electrified heating technologies (Onishi et al., 2014; Razib et al., 2012).
In our research, we investigate the integration of heat pump technology within multi-component distillation systems. Exergy analysis has been widely used in distillation studies to identify thermodynamically efficient designs that minimize second-law losses (Jiang et al., 2019; Tumbalam Gooty et al., 2023). In this study, we examine the conditions under which exergy optimization leads to designs that achieve minimum energy consumption when operated with a heat pump. A key advantage of the exergy methodology is its ability to identify designs compatible with heat pump integrated systems without the need for explicit network modeling. This approach enables the decomposition of unit operations, such as distillation, from the heat pump network, facilitating more efficient system design.
We further benchmark this approach against a simultaneous optimization model that explicitly includes heat pump network design. Results show that, under certain conditions - such as matched thermal qualities of feed and products - exergy optimization alone can yield designs that minimize heat pump work, enabling efficient electrified process heating.
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