摘要
针对有机朗肯循环(ORC)余热利用时无法有效利用余压的问题,构建了双循环余热余压梯级利用系统。先用开式水蒸气朗肯循环对余压进行利用,再用ORC进行余热利用。通过系统建模,对不同有机工质下系统的各项性能指标进行了分析。结果表明,随着蒸发温度的上升,虽然ORC发电量会升高,但系统总发电量会下降。热源的余压越高,双循环系统的优势越明显。对比了5种有机工质,其中R11的总发电功率和系统?效率都最高,而R123的系统热效率最高。系统中,蒸发器和2号膨胀机中的?损最大,其中R236ea在蒸发器中的?损最大,为401.2 kJ,而R11在2号膨胀机中的?损最大,为427.95 kJ。双循环系统总发电功率比单循环高了7.4%,其热效率和?效率分别高出了单循环系统1.23%和4.18%。
To solve the problem that the residual pressure can not be effectively utilized during waste heat utilization by organic Rankine cycle(ORC),a waste heat and residual pressure cascade utilization system based on dual circulation is proposed.It uses an open steam Rankine cycle to utilize the residual pressure first,and then uses ORC for waste heat utilization.The performance indexes of the system under different organic working fluids are analyzed through the system modelling.The results show that with the increase of evaporation temperature,although ORC power generation increases,the total power generation of the system decreases.The higher the residual pressure of the heat source,the more significant advantage of the dual circulation system.Five different kinds of organic working fluids are compared,among which R11 has the highest total power generation and system exergy efficiency,while R123 has the highest system thermal efficiency.In the system,the exergy loss of evaporator and No.2 expander are the largest,among which R236 ea has the largest exergy losses in evaporator,which is 401.2 kJ,while R11 has the largest exergy losses in No.2 expander,which is 427.95 kJ.The total power generation of the dual circulation system is 7.4%higher than that of the single cycle system,and its thermal efficiency and exergy efficiency is 1.23%and 4.18%higher than that of the single cycle system respectively.
作者
张波
李峰
袭著尊
和学豪
顾煜炯
ZHANG Bo;LI Feng;XI Zhuzun;HE Xuehao;GU Yujiong(Huadian Zhangqiu Power Generation Co.,Ltd.,Jinan 250216,China;National Thermal Power Engineering Technology Research Center,North China Electric Power University,Beijing 102206,China)
出处
《电力科学与工程》
2022年第1期50-56,共7页
Electric Power Science and Engineering
基金
中国华电集团公司科技项目(CHDKJ21-02-163)。
关键词
余热余压
有机朗肯循环
梯级利用
有机工质
?
residual heat and pressure
organic Rankine cycle
cascade utilization
organic working fluid
exergy
