Carbon residue prediction of coal combustion in circulating fluidized bed boiler based on particle tracer
The carbon residue is essential for reflecting the combustion efficiency of CFB boiler,the accurate prediction of carbon residue has significance for CFB operation and design.Based on the trajectory and residence time of particles in the furnace,the carbon content of coal particles out of the furnace was calculated.The effects of residence time,furnace temperature,coal rank,and excess air ratio were investigated.It is found that the coal particle with longer residence time has lower carbon content.When the bed temperature increases from 800 ℃ to 900 ℃,the carbon residue decreases by about 40％ -50％ .Increasing the excess air ratio from1.05 to 1.3,the carbon residue reduces by 10％ -30％ .The rank of coal is the key factor to carbon residue.The volatile,fixed carbon content and reactivity of coal determine the burnout behavior.By comparing the calculated results by the CFB design method and the experimental data,it is proved that the prediction of residual carbon based on the trajectory method is reasonable.
carbon residueparticle trajectorycirculating fluidized bedresidence time
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NSTL
万方数据
