The operating point of primary air fans for many large-capacity CFB boilers having already been put into operation is far from the economic operating point.For this

through analysis of boiler structure for two kinds of CFB boilers

and analysis of characters for coal quality

a regularity of type selection for primary air fans has been obtained

i.e.the abundance of type selection should be changed along with boiler structure and coal quality characters

boasting important significance for design and type selection of primary air fans for large-capacity CFB boielrs.