600 MW超临界锅炉尾部对流受热面积灰监测研究

Research on ash monitoring at the end convection heating area of 600 MW supercritical boiler

中文关键词: 尾部对流受热面  积灰  污染率  吹灰策略  运行指导

英文关键词: tail convective heating surface  soot deposition  pollution rate  soot blowing strategy  operation guidance

中文摘要:

      为实现电厂按需吹灰,基于热平衡原理选取污染率作为积灰监测指标反映受热面的积灰程度,针对尾部对流受热面建立积灰监测模型并形成污染率计算流程。以某台600 MW超临界变压运行直流炉为实施对象,对尾部低过、低再及省煤器三个受热面进行污染率计算分析,结合积灰监测结果和安全经济性原则对尾部受热面的吹灰方式进行动态调整,并进行了三天积灰试验。结果表明：建立的积灰监测模型可准确反映受热面的积灰程度；工质吸热量可作为辅助参数判断受热面的积灰情况；整体优化了对象锅炉尾部受热面的吹灰策略,给出吹灰频率可适当减少的吹灰建议,为电厂实际吹灰运行提供了指导与参考。

英文摘要:

      In order to realize on-demand soot blowing in power plants, based on the principle of heat balance, the pollution rate is selected as the monitoring index to reflect the degree of soot deposition on the heating surface, and a monitoring model is established for the tail convective heating surface and a calculation process for the pollution rate is formed. Taking a 600 MW supercritical variable pressure once-through furnace as the object of implementation, the pollution rate of three heating surfaces, low-temperature super-heater, low-temperature re-heater and economizer at the tail, was calculated and analyzed. Combining with the monitoring results of ash accumulation and the principle of safety and economy, the blowing mode of the tail heating surface was dynamically adjusted, and a three-day ash accumulation test was carried out. The results show that the established monitoring model can accurately reflect the degree of ash deposit on the heating surface; the heat absorption of working medium can be used as an auxiliary parameter to judge the ash deposit on the heating surface; the soot blowing strategy of the tail heating surface of the object boiler is optimized as a whole, and the suggestions for reducing the soot blowing frequency appropriately are given, which can provide a reference and guidance for the actual soot blowing operation of the power plant.