盐梯度太阳池Kalina循环发电系统性能研究  

Performance study of a Kalina cycle power system with salt gradient solar pond

作　　者：张学林 张通 薛小代[1,2] 司杨 刘锋 梅生伟[1,2] Zhang Xuelin;Zhang Tong;Xue Xiaodai;Si Yang;Liu Feng;Mei Shengwei(State Key Laboratory of Control and Simulation of Power System and Generation Equipment,Department of Electrical Engineering,Tsinghua University,Beijing 100084,China;School of Qidi(TUS)Renewable Energy,Qinghai University,Xining 810016,China)

机构地区：[1]清华大学电机系电力系统及发电设备控制和仿真国家重点实验室,北京100084 [2]青海大学启迪新能源学院,青海西宁810016

出　　处：《可再生能源》2020年第6期738-744,共7页Renewable Energy Resources

基　　金：国家自然科学基金创新研究群体科学基金资助项目(51621065);青海省科技计划应用基础研究(2018-ZJ-774)。

摘　　要：Kalina循环发电系统是一种典型的低温热源发电系统,具有广阔的应用前景。盐梯度太阳池能够实现连续聚热和跨季节蓄热,可广泛应用于光热发电系统和光热供热系统。文章提出了一种以太阳池储热量为热源的盐梯度太阳池Kalina循环发电系统,并利用Aspen Hysys软件对该系统进行建模。而后根据模拟结果,研究了提热温度、运行压力和氨水浓度对该系统各项性能的影响。此外,还分析了典型工况下,该系统的热力性能。分析结果表明:随着提热温度逐渐升高,盐梯度太阳池Kalina循环发电系统的发电功率、热效率和效率均逐渐增加;随着运行压力逐渐升高,该系统的热效率和效率逐渐升高,并且存在最佳的运行压力1.75 MPa,使得该系统获得最大发电功率;随着氨水浓度逐渐增大,该系统的发电功率也会逐渐增大,但热效率和效率却逐渐降低;当氨水浓度为85%、运行压力为1.75 MPa、提热温度为90℃时,该系统的热效率和效率分别为7.93%,57.59%。As a typical low-temperature heat source power generation technology,Kalina cycle has bright prospects in the fields of solar energy,hot dry rock(HDR)and other renewable energy utilization.Salt gradient solar pond has the characteristics of long-term heat accumulation and cross-season heat storage,and it can be widely used in power generation and other industrial and agricultural fields requiring low-temperature heat sources.In this paper,a Kalina cycle power system is proposed based on salt gradient solar pond.A model of the proposed system is constructed by using the software Aspen Hysys.The influence of extraction temperature,operating pressure,and ammonia-water mass fraction on the thermodynamic performance of the system is analyzed and discussed.Meanwhile,the thermodynamic performance of the system with typical operating conditions is presented.Results indicate that the power generation,thermal efficiency and exergetic efficiency all increase with the increasing extraction temperature.There is an optimal operating pressure of 1.75 MPa to maximize the power generation,but the thermal efficiency and exergetic efficiency will increase with the increasing operating pressure.Moreover,the increase of the working fluid concentration will increase the power generation but the two efficiencies of the system will be reduced.With typical operating conditions(ammonia-water concentration of 85%,operating pressure of 1.75 MPa,and extraction temperature of 90℃),the thermal efficiency and exergy efficiency of the system are 7.93%and 57.59%,respectively.

关 键 词：可再生能源 太阳池 KALINA循环 发电系统 热力性能 

分 类 号：TK519[动力工程及工程热物理—热能工程]