W Flame Boiler Combustion And Operating Characteristics Of Test Research

Anthracite coal is used as fuel in about a quarter of national power plants, and W-shape flame boiler has been used widely to burn bad coal such as anthracite coal in many countries. More than twenty boiler units with W-shape flame, which capability is above 300MW, have been in operation in our country.Although the foreground of this type of boiler is very wide, but some mutual problems exist, for example, lower combustion efficiency, slagging in lower furnace, higher NOx emission, and so on. So it is very important to study the combustion and operation characteristics by testing research.This paper briefly introduced the background of this task, combustion principle, and investigation actuality. Accoroading commissioning and testing research content in four boiler units which installed in Shandong Heze Plant and Liaocheng Plant, combustion and operation characteristics of two different capability boiler has been analyzed and compared.This paper detailed the content and result of testing research, advantage and disadvantage of W-shape boiler has been compared too. Evaluation for combustion and operation characteristics was done, then suitable operation mode and combustion control parameters that was consided to improve operating economics of boiler was proposed.This paper indicate some characteristics of this type of boiler, for example, balanced staring-up, flexible load adjusting and steam temperature adjusting, better applicability for change of coal heat value, better lower-load capability, better combustion efficiency when the pulverized coal fineness is eligible. But slagging occurs normally when the melting point temperature of fuel is lower than design value. Compare with corner-fired boiler, this type of boiler requires strict air flow distribution and oxygen control because it is sensitive to oxygen changing, so one method of improving combustion efficiency is increasing operating oxygen value and keeping fine air distribution. Combustion efficiency is affected by pulverized coal fineness...