摘要
天然气燃烧后排烟温度较高,直接排放造成巨大的能源浪费,余热回收是提高能源利用率的重要手段。本文系统分析了间壁式换热、热管换热、喷淋+热泵换热和烟气梯级换热(“三塔”换热)4种天然气烟气余热回收技术,阐述了每种技术的应用路线和研究现状,定性对比分析了4种余热回收技术的优点和局限性,并在同一运行条件下对其余热回收能力及经济性进行了定量比较。结果表明,由于天然气烟气露点温度较高(50~57℃),烟气绝大部分余热量以潜热形式存在,基于全热交换的烟气余热回收技术可以回收烟气露点温度以下的潜热,锅炉烟气余热回收能够提升供热能力9%以上,且具有良好的经济性。
The temperature of natural gas-fired flue gas is high and its emissions waste a large amount of thermal energy.Recovery of waste heat is important to increase energy utilization efficiency.Four waste heat recovery techniques for natural gas-fired flue gas,including wall-type heat exchange,heat pipe exchanger and heat recovery by sprinkler+heat pump as well as flue gas cascade heat transfer(’three towers’heat transfer)are systematically analyzed.The technical route of each technology and current research status are summarized.The advantages and limitations of the four techniques are explored,and the waste heat recovery and economy of the four technologies are compared quantitatively under the same operation conditions.The results show that,due to high dew point(50~57℃)of flue gas with considerable latent heat,the waste heat recovery technologies based on total heat transfer can fully recover the latent heat of the natural gas-fired flue gas below dew point,and improve the heating capacity by more than 9%,which has high economic efficiency.
作者
时国华
刘彦深
李晓静
赵望灵
SHI Guohua;LIU Yanchen;LI Xiaojing;ZHAO Xilin(School of Energy,Power and Mechanical Engineering,North China Electric Power University,Baoding 071003,China;School of Architecture,Tsinghua University,Beijing 100084,China)
出处
《热力发电》
CAS
北大核心
2020年第2期1-9,共9页
Thermal Power Generation
基金
国家自然科学基金项目(51706115)
中央高校基本科研业务费专项资金资助(2017MS124)。
关键词
天然气
烟气
余热回收
热管
全热交换
喷淋+热泵换热
经济性
natural gas
flue gas
waste heat recovery
heat pipe
total heat transfer
spray and heat pump heat transfer
economy
