为了有效利用液化天然气（liquefied natural gas, LNG）的冷能并对燃气轮机废气中的CO₂进行液化处理，提出了一种利用LNG冷能液化CO₂及CO₂动力循环的新工艺，该工艺在常规朗肯循环的基础上增加了再热循环和回热循环并且设置了多流股换热器。利用化工过程模拟软件对工艺流程进行模拟并且对回流温度、级间冷却温度和循环的最高温度和压力进行敏感性分析，得到最佳运行参数。采用分析的方法，对系统的效率、比功和CO₂的液化率等系统评价指标进行分析计算，并与现有工艺进行对比分析，得到新工艺的效率为54.16%，比功为335.9 kJ/kg LNG，CO₂的液化率为0.621 7 kg/kg LNG，可知新工艺的评价指标均优于现有工艺。并且以效率最高为目标，液化后的CO₂温度作为约束条件，采用Original优化模式对工艺流程的参数进行优化，优化后的效率为54.28%，比功为337.5 kJ/kg LNG，系统性能进一步提升。

In order to effectively utilize LNG(liquefied natural gas) cold energy and liquefy CO₂ in gas turbine exhaust gas, a new process of LNG cold energy to liquefy CO₂ and CO₂ power cycle was proposed. In this process, Reheat cycle and regenerative cycle were added on the basis of conventional Rankine cycle, and multi-flow strand heat exchanger was set up. Chemical process simulation software was used to simulate the process flow and sensitivity analysis of reflux temperature, interstage cooling temperature and maximum circulating temperature and pressure was carried out to obtain the best operating parameters. Exergy efficiency, specific work and CO₂ liquefaction rate of the system were analyzed and calculated by exergy analysis. Exergy efficiency of exergy was 54.16%, specific work was 335.9 kJ/kg LNG, and CO₂ liquefaction rate was 0.621 7 kg/kg LNG in a new process. The evaluation indexes of the new process were better than those of the existing process. As for the exergic efficiency, exergic efficiency of exergic was as the highest and the temperature of CO₂ after liquefied was as the constraint condition, exergic efficiency of exergic was 54.28% and specific power was 337.5 kJ/kg LNG, so the system performance was further improved.