Among various supercritical carbon dioxide cycles, the supercritical recompression carbon dioxide cycle can well adapt to the high temperature of the exhaust gas of the solid oxide fuel cell-gas turbine system to augment power generation. Nevertheless, even after the recovery by the supercritical recompression carbon dioxide cycle, the exhaust gas still contains a large amount of unutilized waste energy. Few studies introduce low-temperature cycles to build cascade cycle systems, which are very likely to address this issue effectively. From the perspectives of energy, exergy, environmental and economic indexes, this article analyzes and compares the improvement potential of integrating four common low-temperature cycles, including organic Rankine cycle, transcritical carbon dioxide cycle, Kalina cycle, and organic flash cycle. Different key operating parameters are considered in-depth and optimized by a genetic algorithm. The results illustrate that in terms of efficiency, the introduction of the organic Rankine cycle is the most outstanding since it can reach the highest energy efficiency of 72.74–73.55% (exergy efficiency of 70.22–71.01%) across wide operation conditions. In terms of cost, the coupling of Kalina cycle is suggested due to the lowest capital cost of 19.94 $/h. The environmental penalty of the four systems all accounts for 14.73% of the total cost. As a consequence, the pros and cons of four common low-temperature cycles are fully demonstrated, which can provide references for the power plant planning.

在各种超临界二氧化碳循环中，超临界再压缩二氧化碳循环能够很好地适应固体氧化物燃料电池-燃气轮机系统废气的高温，以增加发电量。然而，即使经过超临界再压缩二氧化碳循环回收后，废气中仍含有大量未利用的废能。很少有研究引入低温循环来构建级联循环系统，这很可能有效地解决这个问题。本文从能源、火用、环境和经济指标的角度，分析比较了有机朗肯循环、跨临界二氧化碳循环、卡林纳循环和有机闪蒸循环四种常见低温循环集成的改进潜力。不同的关键操作参数被深入考虑并通过遗传算法进行优化。结果表明，在效率方面，有机朗肯循环的引入是最突出的，因为它可以在广泛的操作条件下达到72.74-73.55%（火用效率70.22-71.01%）的最高能效。在成本方面，由于最低资本成本为 19.94 美元/小时，因此建议采用 Kalina 循环耦合。四个系统的环境罚款均占总成本的14.73%。从而充分论证了四种常见低温循环的优缺点，可为电厂规划提供参考。有机朗肯循环的引入最为突出，因为它可以在广泛的操作条件下达到 72.74-73.55% 的最高能效（火用效率为 70.22-71.01%）。在成本方面，由于最低资本成本为 19.94 美元/小时，因此建议采用 Kalina 循环耦合。四个系统的环境罚款均占总成本的14.73%。从而充分论证了四种常见低温循环的优缺点，可为电厂规划提供参考。有机朗肯循环的引入最为突出，因为它可以在广泛的操作条件下达到 72.74-73.55% 的最高能效（火用效率为 70.22-71.01%）。在成本方面，由于最低资本成本为 19.94 美元/小时，因此建议采用 Kalina 循环耦合。四个系统的环境罚款均占总成本的14.73%。从而充分论证了四种常见低温循环的优缺点，可为电厂规划提供参考。四个系统的环境罚款均占总成本的14.73%。从而充分论证了四种常见低温循环的优缺点，可为电厂规划提供参考。四个系统的环境罚款均占总成本的14.73%。从而充分论证了四种常见低温循环的优缺点，可为电厂规划提供参考。