【摘要】 针对梯级利用液化天然气（LNG）在气化过程中释放冷能的同时回收烟气中的二氧化碳（CO₂）问题,提出一套氮气回热布雷顿（Brayton）循环与乙烯-丙烷二级有机朗肯循环（ORC）联合的冷热电三联供系统。采用数值模拟软件对系统进行模拟计算。分析蒸发压力、蒸发温度、氮气质量流量对系统性能的影响。模拟结果表明,在氮气质量流量为45 000 kg×h^-1时,系统的净输出功可达到2 834.1 kW,热效率为42.7%,?效率为35.1%。经济分析结果表明,系统的年度净资产（NE）为4 209 633.277$,折旧回收期（DPP）为4.23 a。研究成果对环境保护具有重要意义。更多还原

【Abstract】 A combined cooling, heating and power supply system with a nitrogen regenerative Brayton cycle and an ethylene-propane secondary organic Rankine cycle（ORC） was proposed for cascade utilization of cold energy released by liquefied natural gas（LNG） during gasification while recovering carbon dioxide（CO₂） from flue gas. The system was simulated and calculated by numerical simulation software. Effects of evaporation pressure, evaporation temperature and nitrogen mass flow rate on system performance were analyzed. The simulation results show that when nitrogen mass flow is 45 000 kg×h^-1, the net output of the system can reach 2834.1 kW with thermal efficiency of 42.7% and exergy efficiency of 35.1%. The results obtained through economic analysis show that the system annual net assets（NE） is 4 209 633.277 $, and the depreciation payback period（DPP） is 4.23 a. These results are useful for environmental protection.更多还原