基于表面温度控制的卫燃带设计方法

提出了基于卫燃带向火面表面温度计算及控制的卫燃带设计方法,并根据炉内火焰与水冷壁管及卫燃带间的集总参数换热模型及卫燃带向火面至水冷壁管内工质各个环节的传热模型,建立了将卫燃带向火侧的表面温度与锅炉负荷、卫燃带材料导热系数、卫燃带敷设厚度与面积关联的代数模型,并运用该模型对1台燃用阳沁无烟煤的1025 t/h四角切圆燃烧煤粉锅炉的卫燃带进行了传热计算.结果表明:锅炉负荷对卫燃带的表面温度影响最大,并且成近似线性关系;卫燃带厚度对表面温度的影响显现出对数函数的特性;卫燃带表面温度随材料导热系数的下降快速升高;卫燃带表面温度随面积的增加而缓慢增加;计算结果与国内1025 t/h同类型煤粉锅炉卫燃带的实际应用情况吻合.

A Way of Design Refractory Belts Based on the Control of its Surface Temperature

A way of designing refractory belts,which are based on the calculation of their flame-faced surface temperature,and the latter's control,is being proposed,and utilizing heat transfer models,with which a correlation is being established of the furnace flame's parameters with those of the water wall tubes' and the refractory belts',as well as heat transfer models which connect the refractory belts' flame-faced surface with the working medium in all water wall tubes sections;herewith constructing an algebraic model,which establishes a correlations between the temperature of the refractory belts' flame-faced surface and the boiler's output,the refractory material's thermal conductivity and the belt's thickness,as well as its surface area.This model was used to perform heat transmission calculation of the refractory belt of a 1025 t/h tangentially fired boiler running on Yangqin anthracite.Results indicate that the boiler output has the most pronounced influence on the refractory belt's surface temperature,in an approximately linear way;the relationship between the refractory belt's thickness and its surface temperature can be represented by a log function;the refractory belt's surface temperature increases rapidly with decreasing conductivity of the refractory material;the refractory belt's surface temperature rises slowly with its coverage area.Calculation results agree with actual refractory belt's behavior as observed with pulverized coal firing 1025 t/h boilers of domestic manufacture and of the same type.