有机朗肯循环发电系统中换热过程模拟与系统经济性分析

有机朗肯循环发电系统中的能量主要损失在换热设备中。换热设备性能对其发电效率有着直接的影响。为提高有机朗肯循环发电系统的经济性,以最小电力生产成本为目标函数,建立经济性模型,并以实际搭建的有机朗肯循环发电系统对模型进行优化,对安装预热器和过热器的经济性进行分析。研究结果表明:电力生产成本主要受热源介质流量、冷却水流量、系统发电功率、蒸发器节点温差及蒸发温度的影响;在有机朗肯循环发电系统中,尤其是在中大型发电系统中,预热器的安装是经济可靠的;过热器的安装对电力生产成本的增加值较小,而其可提高系统的稳定性、延长系统的使用寿命。

Simulation and economic analysis of heat exchange process in organic Rankine cycle power generation system

The energy in organic Rankine cycle power generation system is mainly lost in the heat exchange equipments.The performance of heat exchange equipments has a direct impact on its power generation efficiency.In order to improve the economy of the organic Rankine cycle power generation system,taking the minimum electricity production cost as the objective function,an economic model is established and optimized with the actual organic Rankine cycle power generation system.The economy of installing preheater and superheater in the system is analyzed.Research results show that:the production cost of electricity(COE)is mainly affected by heat medium flow rate,cooling water flow rate,generated power of system,pinch-point temperature difference of evaporator and evaporating temperature.In the organic Rankine cycle power generation system,especially in large or medium power generation system,preheater installation is economical and reliable.The installation of superheater will increase the production cost of electricity slightly,but it can improve the stability and service life of the system.