有机朗肯循环与蒸汽压缩制冷循环耦合系统联产性能研究

On the performance of coupling cogeneration system of organic Rankine cycle and vapor compression refrigeration cycle

以中高温地热作为驱动热源,将有机朗肯循环与蒸汽压缩制冷循环相结合,提出了中高温地热冷热电联产系统。基于热力学第一和第二定律,构建了冷热电联产热力学优化模型,并对热源温度120~200℃范围内的系统性能进行了模拟计算和分析,比较了Cyclohexane、Pentane、n-Heptane、n-Octane、n-Nonane、n-Decane、n-Hexane及Isopentane 8种不同工质的热力学性能。结论显示:有机朗肯循环与蒸汽压缩制冷循环耦合系统可以实现冷热电联产,根据季节需求不同灵活调控;Isopentane发电性能最佳,Iso⁃pentane制冷性能最佳;回收冷却水排放的热量可以大大提高耦合系统热效率,热效率高达90%多。

The medium and high temperature geothermal energy is used as the driving heat source,and the organic Ran⁃kine cycle and the steam compression refrigeration cycle are combined to put forward the Cogeneration system.Based on the first and second laws of thermodynamics,a thermodynamic optimization model of CCHP is established,and the per⁃formance of the system in the temperature range of 120-200℃is simulated and analyzed.The thermodynamic perfor⁃mance of eight different refrigerants,cyclohexane,pentane,n-heptane,n-octane,n-nonane,n-decane,n-hexane and isoopentane are compared.The conclusion shows that:the coupling system of organic Rankine cycle and steam compres⁃sion refrigeration cycle can realize the combined cooling and heating power generation,which can be flexibly controlled according to the seasonal demand;the power generation performance of isopentane is the best,and the refrigeration per⁃formance of isopentane is the best;the thermal efficiency of the coupling system can be greatly improved(more than 90%)by recovering the heat discharged from the cooling water.