摘要
火力发电是高耗能、高耗水行业,回收火电厂烟气中水分及余热能起到显著的节能、节水效果。通过单根20 nm孔径陶瓷膜进行烟气中水分及余热回收实验,研究不同烟气流量(4～18L/min)、烟气温度(50～70℃)、烟气相对湿度(40%～100%)和冷却水流量(0.5～2.0 L/min)对回收性能的影响。结果表明:水回收速率随烟气流量、烟气温度、烟气相对湿度增加而上升;水回收效率随烟气温度、烟气相对湿度增加而上升,随烟气流量增加而下降;冷却水流量变化对水回收速率和效率没有影响;烟气对流凝结努塞尔数(Nuf)用于评价烟气在陶瓷膜内的传热性能,其随烟气流量、烟气相对湿度、冷却水流量增加而升高;大烟气流量工况时Nuf随烟气温度增加而升高,小烟气流量时Nuf随烟气温度增加呈先升高后降低趋势。研究结果对于陶瓷膜在火电厂烟气中实际应用具有理论指导意义。
Thermal power generation is a high energy consumption and water consumption industry,and recovery of water and waste heat from the flue gas of thermal power plants can play a significant energy-saving and water-saving effect.On the basis of experiment of water and waste heat recovery from flue gas by single 20-nm pore-sized ceramic membrane,the effects of flue gas flow rate(4~18 L/min),flue gas temperature(50~70℃),relative humidity of flue gas(40~100%)and cooling water flow rate(0.5~2.0 L/min)on the recovery performance of flue gas were studied.The results show that,the water recovery rate increased with the flue gas flow rate,flue gas temperature and relative humidity of flue gas.The water recovery efficiency rose with the flue gas temperature and relative humidity,and decreased with the increasing gas flow rate.The variation of cooling water flow had no effect on water recovery rate and water recovery efficiency.The flue gas convective condensation Nusselt number increased with the flue gas flow,relative humidity of flue gas and cooling water flow.In the case of large flue gas flow,the flue gas convective condensation Nusselt number increased with the flue gas temperature,and when the flue gas flow was small,the flue gas convection condensation Nusselt number increased at first and then decreased with the increasing flue gas temperature.The results are of theoretical significance for practical application of the ceramic membrane in flue gas of thermal power plants.
作者
陈海平
谢天
杨博然
冯义钧
CHEN Haiping;XIE Tian;YANG Boran;FENG Yijun(National Thermal Power Engineering&Technology Research Center,North China Electric Power University,Beijing 102206,China)
出处
《热力发电》
CAS
北大核心
2018年第11期46-52,共7页
Thermal Power Generation
基金
中央高校基本科研业务费专项资金资助(2015ZZD11)~~
关键词
陶瓷膜
烟气
水蒸气
余热
水回收速率
水回收效率
烟气对流凝结努塞尔数
ceramic membrane
flue gas
water vapor
waste heat
water recovery rate
water recovery efficiency
flue gas convection condensation Nusselt number
