绿色环保工质CO2用于LNG预冷段的循环性能

The recycling performance of green working medium CO2 in the pre-cooling stage of LNG

文章对跨临界CO2预冷LNG制冷循环进行了热力学理论研究和数值模拟分析,并采用加回热器和膨胀机的跨临界CO2预冷LNG单级压缩循环分析了CO2用于制冷循环的实际意义。数值研究结果表明:整个循环过程存在最适宜的高压压力,使得循环系统的制冷系数达到最大;带回热器的制冷循环系统中回热器所交换的换热量是影响COP的一个重要因素。同时通过对CO2制冷循环系统的不断优化提高了COP。

In this paper,the thermodynamic theory and numerical simulation of Transcritical CO2 precooled LNG refrigera-tion cycle are studied,and the practical significance of CO2 used in the refrigeration cycle is analyzed by using the single-stage compression cycle of Transcritical CO2 precooled LNG with regenerator and expander.The numerical results show that there is the most suitable high pressure in the whole cycle process,which makes the refrigeration coefficient of the cycle system reach the maximum;the heat exchange of the regenerator in the refrigeration cycle system with heat exchanger is an important factor affecting cop.At the same time,cop is improved by continuous optimization of CO2 refrigeration cycle system.