基于闪蒸换热的高炉冲渣水余热利用热效率及[火用]效率分析

Thermal efficiency and efficiency analysis of waste heat utilization of blast furnace slag flushing water based on flash heat exchange

文章以海水淡化为研究对象,针对海水淡化中闪蒸与换热器换热过程开展热力学分析,建立了闪蒸和换热器换热过程热效率及[火用]效率数学模型,并对国内某钢铁厂海水淡化系统实际运行数据进行计算,结果表明通过三级闪蒸换热,可以将27.1℃的清洁水加热到74.3℃,此时闪蒸过程热效率为27.27%,[火用]效率为46.95%;换热器换热过程热效率为89.58%,[火用]效率为94.67%;总热效率为24.43%,总[火用]效率为44.45%。

Based on the thermodynamic analysis of flash and heat transfer in seawater desalination,a mathematical model of thermal efficiency and exergy efficiency in flash and heat transfer process was established,and the actual operation data of a seawater desalination system in a domestic iron and steel plant were calculated.The results show that the clean water at 27.1℃can be heated to 74.3℃by three-stage flash heat transfer.The thermal efficiency of flash evaporation process is 27.27%,the exergy efficiency is 46.95%;the thermal efficiency of heat exchange process is 89.58%,the exergy efficiency is 94.67%;the total thermal efficiency is 24.43%,the total exergy efficiency is 44.45%.