循环流化床机组锅炉深度调峰负荷水循环安全性分析  

Safety analysis for boiler thermal-hydraulic circulation with severe peak load regulation of a CFB unit

作　　者：聂鑫 谢海燕 杨冬[3] 刘辉[1] 周科[1] 周志培[1] 李宇航[1] 柳宏刚[1] NIE Xin;XIE Haiyan;YANG Dong;LIU Hui;ZHOU Ke;ZHOU Zhipei;LI Yuhang;LIU Honggang(Xi'an Thermal Power Research Institute Co.Ltd.,Xi'an 710054,China;Nuclear Power Institute of China,Chengdu 610213,China;State Key Laboratory of Multiphase Flow in Power Engineering,Xi'an Jiaotong University,Xi'an 710049,China)

机构地区：[1]西安热工研究院有限公司,陕西西安710054 [2]中国核动力研究设计院,四川成都610213 [3]西安交通大学动力工程多相流国家重点实验室,陕西西安710049

出　　处：《中南大学学报（自然科学版）》2022年第7期2766-2776,共11页Journal of Central South University:Science and Technology

基　　金：国家重点研发计划项目(2017YFB0902100)。

摘　　要：为了提升燃煤机组深度调峰能力,针对某循环流化床(CFB)机组锅炉进行深度调峰负荷试验研究,并对锅炉水循环的安全性进行分析。以现场测试锅炉低负荷数据为基础,建立循环流化床锅炉水循环计算模型,并对锅炉炉水循环特性相关参数进行计算,得到深度调峰负荷下锅炉循环倍率、流量分配、循环流速和水冷壁金属壁温等的分布。研究结果表明:锅炉负荷可安全降至最大连续蒸发负荷的27%,并维持稳定运行,主蒸汽温度大于530℃,脱硝反应器进口烟温在315℃以上,炉膛负压正常,环保指标正常,各受热面温度不超限,但左、右侧床温存在偏差。深度调峰负荷下锅炉的循环倍率均满足安全运行要求,且有足够的安全裕度;流量分布合理,循环流速均在安全范围内,金属温度能够满足材料强度和抗氧化的要求,且在正常热负荷下水冷壁管不会发生停滞现象,但若炉膛热负荷和床温进一步降低,则有可能造成循环停滞。To improve the peak shaving capability,the deep peak load regulation test was carried out and the safety analysis of boiler water circulation for a circulating fluidized bed(CFB)unit was conducted.Based on the low load test data of the boiler,the mathematical model of water circulation calculation for CFB boiler was established and the boiler water circulation related parameters were calculated.The distribution of circulation ratio,flow distribution,circulation velocity and metal temperatures of water wall were obtained under deep peak load.The results show that the boiler load can be safely reduced to 27%of BMCR(boiler maximum continuous rating)and stable operation can be maintained.The main steam temperature is higher than 530℃,and denitration reactor inlet flue gas temperature is above 315℃.The furnace negative pressure and the environmental protection index are normal,the heat surfaces temperature is within the temperature limit,but there is deviation between the left and right bed temperature.The circulation ratio with severe load regulation can meet the requirements of boiler safe operation with enough safety margin.The rate of flow distribution is reasonable and the circulation velocity are within the safe range.The metal temperature can meet the demands of material strength and antioxidation,and stagnation phenomenon of the water wall pipe will not occur under normal heat load.However,if the furnace heat load and bed temperature continue to decrease,it may cause circulation stagnation.

关 键 词：深度调峰 循环流化床 水动力参数 水冷壁 

分 类 号：TK224.2[动力工程及工程热物理—动力机械及工程]