Thermodynamic integration of HTGR nuclear heat into the Barrancabermeja refinery

Abstract

Decarbonizing refinery process heat and hydrogen production remains a major challenge for industrial net-zero pathways. High-temperature gas-cooled small modular reactors (HTGR–SMRs) are promising candidates because they combine high outlet temperatures, modular deployment, and inherent safety. This work develops a unified thermodynamic–exergy framework based on Pinch Point analysis, differential heat-transfer integration, and entropy-generation balances to assess HTGR coupling with refinery heat, hydrogen, and cogeneration systems under realistic industrial conditions. Results show that the main thermodynamic difference among the evaluated configurations is not the presence of the Once-Through Steam Generator (OTSG) itself, but the thermal matching between the nuclear heat source and refinery demands. Indirect steam delivery through an OTSG and direct helium supply to multiple refinery processes achieve comparable refinery-level performance, with second-law efficiencies of approximately 62.57%. In contrast, direct helium supply to the topping process—one of the most critical units in the refinery—reaches a lower efficiency of about 57.5%, corresponding to a relative improvement of approximately 8.8% for the OTSG and multi-process configurations. This indicates that, although direct helium exchange preserves a higher temperature potential, it suffers from greater thermal mismatch and higher irreversibility at the reactor–process interface, particularly when applied to single high-demand units such as topping. Applied to the Barrancabermeja Refinery, the proposed architecture could supply about 400 MWth of process heat while supporting cogeneration, low-carbon hydrogen pathways, and avoiding on the order of 3 Mt CO₂/year.