空冷机组空气-烟气余热利用综合分析  

Comprehensive Analysis of Air-Flue Gas Waste Heat Recovery in Air Cooling Units

作　　者：杨勇平[1] 许诚[1] 徐钢[1,2] 方亚雄[1] 吴影[1] 

机构地区：[1]华北电力大学国家火力发电工程技术研究中心,北京102206 [2]重庆大学低品位能源利用技术及系统教育部重点实验室,重庆404100

出　　处：《动力工程学报》2013年第11期907-912,共6页Journal of Chinese Society of Power Engineering

基　　金：国家重点基础研究发展计划资助项目(973计划)(2009CB219801);国家自然科学基金联合基金资助项目(U1261210);重庆大学低品位能源利用技术及系统教育部重点实验室开放基金资助项目(KH3381);国际科技合作资助项目(2010DFA72760-609)

摘　　要：在分析空冷机组运行特点的基础上,提出了一种空气-烟气余热联合回收系统,即空冷岛出口的热空气作为锅炉燃烧用风,进入空气预热器被加热,同时在锅炉尾部加装低温省煤器,加热低压凝结水,以节省汽轮机抽汽量.以某典型600MW亚临界直接空冷机组为例,分析了空气-烟气余热联合回收系统的热力学特性和节能效果.结果表明:在典型工况下,空气预热器入口温度可提高约25K,机组供电煤耗降低约1.93g/(kW·h),年节约标准煤约7 000t,节约燃料费700余万元(按机组年运行5 500h,标准煤价格为1 000元/t计算),经济效益显著.Based on detailed analysis of operation characteristics of an air cooling unit,a combined air-flue gas waste heat recovery system was proposed,in which the hot air from air cooling unit is to be heated in air preheater for purposes of boiler combustion,and simultaneously,the low temperature economizer set at boiler tail is used to heat the low-pressure condensed water,thus saving the steam extracted from steam turbine.Taking a typical 600 MW subcritical direct air cooling unit as an example,the thermodynamic characteristics and energy-saving effects of its air-flue gas waste heat recovery system were analyzed.Results show that obvious economical effects can be obtained for the air-cooling unit under typical working conditions,with an increased inlet temperature of air preheater by 25 K,a reduced power supply coal consumption by 1.93 g/（kW · h）,an annually economized standard coal consumption by 7 000 t,equivalent to 7 million RMB fuel cost （based on the coal price of 1 000 RMB/t with an annual running time of 5 500 hours）.

关 键 词：空冷机组 余热利用 空气-烟气余热联合回收系统 热力学分析 节能效果 

分 类 号：TK115[动力工程及工程热物理—热能工程]