In the landscape of the global energy transition, the efficient thermal valorization of tropical waste biomass is paramount for enhancing regional energy self-sufficiency and fostering a sustainable circular economy. To address the suboptimal utilization of waste coconut shells and the substantial heat loss from supercritical carbon dioxide (sCO 2 ) cooling sources, this study proposes two novel biomass-driven combined power systems: the reheat main compression intermediate cooling cycle (RMIC) and the reheat recompression cycle (RRC), both integrated with a recuperative organic Rankine cycle (RORC). Thermodynamic models were developed using the Python platform. Employing energy and exergy analysis methodologies, the study investigated the impact of the split ratio ( SR ) and its synergistic interaction with the pressure ratio ( PR ) on system performance. Findings reveal that the SR governs the dynamic migration of heat exchanger pinch points by regulating the thermal capacity flow rate matching. Under multi-parameter coupling, the RMIC exhibits superior adaptability under high-pressure-ratio conditions (achieving 51.09% thermal efficiency at PR =4.5), whereas the RRC performs better in low-pressure-ratio scenarios (49.74% at PR =3). Exergy analysis confirms that irreversible heat transfer within the heater and reheater constitutes the predominant source of exergy destruction. This study systematically elucidates the performance evolution of sCO 2 -ORC systems under multivariable coupling, providing crucial optimization guidelines and engineering references for high-efficiency cascading thermal systems tailored to biomass energy utilization.
Wu et al. (Wed,) studied this question.