基于TC-CCES的冷热电联供系统热力性能分析

Analysis of Thermodynamic Performance of Combined Cooling,Heating and Power System based on TC-CCES

为了更好地理解CO_(2)作为储能工质在热力学方面的特性,基于跨临界压缩二氧化碳储能系统(TC-CCES),结合CO_(2)易液化的特性,采用Aspen Plus软件构建了冷热电联产(CCHP)系统热力学模型,分析了回热器热水流量、低压节流阀压降及第一级压缩机出口压力对CCES-CCHP系统性能的影响。结果表明:在基础运行工况下,CCES-CCHP系统电效率为41%,能量效率为1.16;当回热器热水流量、第一级压缩机出口压力变化时,系统电效率与能量效率变化趋势相反;当低压节流阀压降增大时,系统电效率和能量效率均呈下降趋势;CCES-CCHP系统与TC-CCES系统相比,能量利用效率提升19.50%。

To better understand the thermodynamic characteristic of carbon dioxide as energy storage working medium,the thermodynamic model of combined cooling,heating and power(CCHP)system was constructed by Aspen Plus software,combined with the easy liquefaction characteristics of carbon dioxide based on the transcritical compressed carbon dioxide energy storage(TC-CCES)system.The effects of hot water flow rate of regenerator,pressure drop of low-pressure throttle valve and outlet pressure of first stage compressor on the performance of CCES-CCHP system were analyzed.The results show that the electrical efficiency of the CCES-CCHP system is 41%and the energy efficiency is 1.16 under the condition of base case;when the hot water flow rate of regenerator and the outlet pressure of the first stage compressor change,the change trends of electric efficiency and energy efficiency of the system are opposite;when the pressure drop of low-pressure throttle valve increases,the electrical efficiency and energy efficiency of the system show a downward trend;compared with TC-CCES system,CCES-CCHP system improves energy utilization efficiency by 19.50%.