双级燃尽风在墙式燃烧锅炉上的应用  

APPLICATION OF TWO-STAGE OFA IN WALL-FIRING PULVERIZED COAL BOILER

作　　者：张玉斌 孙树翁 王培亮 崔星源 刘欣 苗雨旺 李明 林淑胜 

机构地区：[1]烟台龙源电力技术股份有限公司,山东烟台264006 [2]国电蚌埠发电有限公司,安徽蚌埠233411

出　　处：《热力发电》2012年第9期72-75,共4页Thermal Power Generation

摘　　要：常规墙式燃烧锅炉单层燃尽风布置方式存在燃尽风对整个炉膛横断面的覆盖度较低,燃尽风与烟气混合程度较弱,NOx排放浓度较高的缺陷。为此,以国电蚌埠发电有限公司(蚌埠电厂)一期超临界2×600MW机组锅炉为例进行燃烧方式改造。结果表明,设置双级燃尽风不仅能够增大燃尽风总量,而且使锅炉NOx排放浓度降低20%左右。同时,由于2层燃尽风喷口错列布置,扩大了气流对炉膛断面的覆盖范围,增强了燃尽风与炉内烟气的混合强度,使未燃尽物在有限的高度内充分燃烧,提高了锅炉燃烧效率。Drawbacks such as low over-fire air(OFA) coverage in the whole furnace cross section,weak mixing between OFA and the flue gas,and the high NOx emission occur in the conventional wall-firing boiler with single stage OFA.Thus,two-stage OFA was experimentally studied by taking the supercritical 2×600 MW units boiler of first phase project in Guodian Bengbu Power Generation Co.,Ltd.as the object.Results show that,setting two-stage OFA not only can increase the total OFA volume so as to decrease the NOx emission by about 20%,but also can improve the boiler combustion efficiency because staggered arrangement of two layers of OFA nozzles expands the airflow coverage in the furnace cross section,and enhances the mixing between the OFA and flue gas,enabling the unburnt matter fully combust within limited height.

关 键 词：墙式燃烧 锅炉 燃尽风 空气分级燃烧 NOx排放浓度 燃尽率 

分 类 号：TK227[动力工程及工程热物理—动力机械及工程]