摘要
鉴于某电厂3^(#)锅炉水冷壁高温腐蚀情况较为严重,为降低锅炉高温腐蚀速率,通过进行锅炉燃烧调整试验,调整锅炉的运行参数,包括配风方式、运行氧量、煤种等,研究锅炉运行参数调整对水冷壁区域还原性气氛的影响,同时综合分析NO_(x)排放浓度以及锅炉效率等指标的变化关系,找到最优锅炉燃烧方式,降低锅炉高温腐蚀,为锅炉优化运行提供指导。锅炉燃烧调整试验表明,要使水冷壁近壁处烟气中的H_(2)S含量下降,可采取提高运行氧量、减小燃尽风比例等方式;机组负荷450 MW以上时,在原氧量控制值基础上增加0.2%进行调整;采用配风方式调整作为减缓水冷壁高温腐蚀的措施;将周界风开度控制在40%~60%范围;建议日常运行时尽量燃用低硫分煤种;综合考虑水冷壁高温腐蚀、液氨增加费用以及可能对其他设备造成的影响,将脱硝入口NO_(x)浓度控制值提高50 mg/m^(3),即从270 mg/m^(3)~300 mg/m^(3)提高至320 mg/m^(3)~350 mg/m^(3);脱硝入口NO_(x)浓度按照320 mg/m^(3)~350 mg/m^(3)控制,根据试验结果,570 MW、450 MW和300 MW负荷下,B层吹灰器层水冷壁近壁处还原性气氛H_(2)S含量最多可分别降低51μL/L、54μL/L和123μL/L。燃烧器和燃尽风之间区域高温腐蚀情况仍属于“比较严重”程度风险。因此建议加强炉膛水冷壁监测,定期进行水冷壁喷涂。在调研时考虑进行贴壁风防腐蚀改造等措施,必要时可对锅炉燃烧器进行适当改造。
In view of the serious high temperature corrosion of the water wall of 3^(#)boiler,in order to reduce the high temperature corrosion rate of the boiler,the boiler combustion adjustment test was carried out to adjust the operation parameters of the boiler,including air distribution mode,operation oxygen,coal type,etc.At the same time,the relationship between NO_(x)emission concentration and boiler efficiency was comprehensively analyzed to find the optimal boiler combustion mode,reduce the high temperature corrosion of the boiler,and provide guidance for the optimal operation of the boiler.The boiler combustion adjustment test showed that in order to reduce the H_(2)S content in the flue gas near the wall of the water cooling wall,the methods such as increasing the operating oxygen and reducing the ratio of exhausted air to air could be adopted.When the unit load was over 450 MW,the original oxygen control value was adjusted by increasing 0.2%;adjusting the air distribution mode was used as a measure to mitigate the high temperature corrosion of the water wall.The opening of the perime⁃ter wind should be controlled in the range of 40%~60%;it was suggested that low-sulfur coal should be used in daily operation as far as possible.Considering the high temperature corrosion of water wall,the increased cost of liquid ammonia and the possible impact on other equipment,the NO_(x)concentration control value at the entrance of denitrification was increased by 50 mg/m^(3),which was from 270 mg/m^(3)~300 mg/m^(3)to 320 mg/m^(3)~350 mg/m^(3);the concentration of NO_(x)in denitration inlet was controlled according to 320 mg/m^(3)~350 mg/m^(3).Accord⁃ing to the test results,under the loads of 570 MW,450 MW and 300 MW,the concentration of H_(2)S in reducing atmosphere near the wall of layer B soot blower layer could be reduced by up to 51μL/L,54μL/L and 123μL/L,respectively.High-temperature corrosion in the area between the burner and the burnout wind was still a“rel⁃atively serious”risk.Therefore,it was suggested to strengthen the monitoring of furnace water wall and spray water wall regularly.During the investigation,measures such as anti-corrosion reform of adherent wind should be considered,and appropriate reform of boiler burners should be carried out if necessary.
作者
侯荣利
HOU Rong-li(Shanxi Hequ Power Generation Co.,Ltd.,The National Energy Group,Xinzhou 036500,China)
出处
《电力学报》
2021年第4期363-370,共8页
Journal of Electric Power
关键词
锅炉
高温腐蚀
氧量
还原性气氛
锅炉效率
boiler
high temperature corrosion
oxygen content
reducing gas
boiler efficiency
作者简介
侯荣利(1980-),男,工程师,从事火力发电厂锅炉运行调整优化工作,hourongli2005@163.com。
