摘要
对某台1000 MW超超临界双切圆混煤燃烧锅炉的炉膛燃烧过程进行模拟,通过对比计算结果与现场试验结果,综合分析炉膛出口氧体积分数对炉内速度场、温度场、CO和H_(2)S体积分数场的影响。结果表明:随着出口氧体积分数的增加,气流偏转程度减弱,高温气体冲刷水冷壁的可能性减小,煤粉在主燃区内燃烧更充分,温度水平更高,较高的氧量会抑制炉内还原性气氛。还原性气体CO与H_(2)S存在强相关性,CO与H_(2)S的体积分数均随氧体积分数的增加而降低,这与氧化性气氛增强、CO对SO2的还原作用减弱有关。在满负荷条件下,炉膛出口氧体积分数从2.2%增至2.7%,在一定程度上能抑制CO和H_(2)S的生成,当出口氧体积分数增至3.0%以上时,这种抑制作用更明显。为降低锅炉高温腐蚀风险且兼顾NOx排放,在实际运行时应保证炉膛出口氧体积分数不低于3.0%。
The combustion process in the furnace of a 1000 MW ultra-supercritical double tangential circular mixed coal combustion boiler was simulated.The effects of the outlet oxygen volume fraction of the furnace on the velocity field,temperature field,CO and H_(2)S volume fraction field were comprehensively investigated by comparing calculation results with field tests.Results show that when the outlet oxygen volume fraction increases,the degree of airflow deflection is weakened,the possibility of high temperature gas corrosion of the water wall is reduced,the pulverized coal combustion in the main combustion zone is more sufficient,and the temperature is higher.The higher oxygen volume fraction will inhibit the reducing atmosphere in the furnace.There is a strong correlation between the reductive gases of CO and H_(2)S,and the volume fractions of CO and H_(2)S both decrease with the increase of the outlet oxygen volume fraction,which is related to the enhancement of oxidizing atmosphere and the weakening of the reduction effect of CO on SO2.Under the condition of full load,the outlet oxygen volume fraction increases from 2.2%to 2.7%,which can inhibit the generation of CO and H_(2)S to a certain extent.When the outlet oxygen volume fraction increases to more than 3.0%,the inhibition is more significant.In order to reduce the risk of high-temperature corrosion of the boiler and take into account NOxemissions,the oxygen outlet content of the furnace should not be lower than 3.0%during actual operation.
作者
任德军
陈刚
张寅
王鑫
徐俊
江龙
向军
REN De-jun;CHEN Gang;ZHANG Yin;WANG Xin;XU Jun;JIANG Long;XIANG Jun(CHN Energy Changyuan Electric Power Co.,Ltd.,Wuhan 430077,China;CHN Energy Hanchuan Power Generation Co.,Ltd.,Hanchuan 431614,Hubei Province,China;State Key Laboratory of Coal Combustion,Huazhong University of Science and Technology,Wuhan 430074,China)
出处
《动力工程学报》
CAS
CSCD
北大核心
2023年第1期14-23,共10页
Journal of Chinese Society of Power Engineering
基金
国家自然科学基金资助项目(U1910214,U20A20321)
国家能源集团重点科技资助项目(HCYF-SCGC-2021-086)。
关键词
超超临界锅炉
双切圆
混煤燃烧
还原性气氛
数值模拟
ultra-supercritical boiler
double tangential circle
mixed coal combustion
reducing atmosphere
numerical simulation
