Study On The Key Problems In The Design Of Anti-fouling And Anti-coking For High Alkali Coal Fired Boiler

Xinjiang Zhundong coalfield reserves is very large,the rational development and utilization of Zhundong coal resources has an important strategic significance.Zhundong coal ash alkaline oxide?Na₂O,K₂O,Fe₂O₃,CaO,MgO,etc.?is significantly higher?usually content in more than 50%?,especially CaO?20⁴0%?and Na₂O?4¹0%?content is particularly high,significantly higher than the typical bituminous coal,which resulted in the power plant boiler burning Zhundong high alkali coal,the ash melting behavior change and fouling,slagging and domestic low ash fusion temperature coal?Shenhua coal,lignite,etc.?have very different.To serious contamination of high alkali Zhundong coal and coke characteristics in the service of power plant boiler safe operation bring great difficulties and also to the Xinjiang region's new power plant boiler design brings great challenges.Through of Zhundong high alkali coal characteristic analysis and 3MW thermal state test platform trial firing experiment,boiler furnace in coking often appear in the burner region and above the water cooled wall area,more viscous melt liquid slag,indicating that low ash melting point.Arrangement in 750¹100?smoke temperature interval heating surface contamination,coke is serious,boiler reheater,economizer low-temperature heating surface is generally less occurred serious contamination,clogging phenomenon.Select the t lower hermodynamic parameters is the key of high alkali coal boiler coking,design anti contamination.Tower type boiler in high alkali burning coal than PI type boiler with congenital technological advantage,under the same conditions,the tower type boiler optional larger volume,the volume heat load,burner cross-sectional area of heat load,the bottom of the screen the flue gas temperature lower,and therefore more suitable for burning easy coking coal.Optimization of combustion system,heating surface spacing selection,blowing the reasonable layout of the ash system means of high alkali coal boiler anti fouling and slagging design is also very important.