优化尾部受热面降低600MW亚临界锅炉排烟温度的热力计算研究  

Thermodynamic Calculation for the Tail Heating Surface Optimization Used to Reduce the Exhaust Gas Temperature of a 600MW Sub-Critical Boiler

作　　者：刘龙龙[1] 李雪峰[2] 陈云[2] 况敏[1] 王智化[1] 周俊虎[1] 岑可法[1] LIU Longlong LI Xuefeng CHEN Yun KUANG Min WANG Zhihua ZHOU Junhu CEN Kefa(State Key Laboratory of Clean Energy Utilization, Hangzhou 310027, China Zhejiang zheneng Beilun Power Generation Co. Ltd., Ningbo 315800, China)

机构地区：[1]浙江大学能源清洁利用国家重点实验室,浙江杭州310027 [2]浙江浙能北仑发电有限公司,浙江宁波315800

出　　处：《锅炉技术》2017年第1期1-5,共5页Boiler Technology

基　　金：国家重点基础研究发展计划项目(973计划)(2012CB214906)

摘　　要：某电厂1台600 MW亚临界机组锅炉经增容和低氮燃烧改造后存在排烟温度偏高的问题,为有效降低排烟温度同时不影响锅炉安全运行和SCR脱硝装置投运,提出了在SCR脱硝装置出口和空气预热器入口之间的烟道处,合理增加低温省煤器受热面的改造方案。为优化此低温省煤器受热面的布置,借助通用锅炉热力计算BESS软件对两个增设低温省煤器受热面的方案进行热力计算研究,即方案A和方案B(分别在原有省煤器受热面积的基础上增加66.7%和100%)。结果表明:不同负荷下两个方案均可有效降低排烟温度,且方案B各项指标更佳,降低排烟温度约14℃,提高锅炉效率约0.6%,节约运行成本约557万元/年。此外,针对方案B对锅炉运行可能造成的各种影响进行了详尽的预判性评估。A 600 MW sub-critical boiler suffers from high exhaust gas temperatures after the retrofits of capacity increase and low-NOx combustion. To effectively reduce the high exhaust gas temperature while not affect the boiler and SCR denitrification operations, a tail heating surface retrofit characterized by reasonably increasing some low-temperature economizer heating surface in the flue region between the SCR denitration outlet and the air preheater inlet was proposed. In order to optimize the low-temperature economizer heating surface, a software BESS was used to carry out thermodynamic calculations for two schemes, schemes A and B （The increases of schemes A and B equal to 66.7% and 100% of the original economizer heating surface, respectively）. Results show that two schemes under different loads can effectively reduce the exhaust gas temperature. However, the scheme B presents a better performance, where the exhaust gas temperature can be reduced by about 14℃, the boiler efficiency increased by about 0.6%, and the boiler＇s operation cost saved by about 5.57 million yuan per year. In addition, a detailed assessment of effects of the scheme B on the boiler operations was provided.

关 键 词：600MW亚临界锅炉 省煤器 排烟温度 尾部受热面 热力计算 

分 类 号：TK223.3[动力工程及工程热物理—动力机械及工程]