The influence of adding desulphurizor upon various heat losses in a CFB boiler has been analysed.It is clear from analysis that the sequence of severity due to each affected heat loss is as follows:the effect upon heat loss in desulphurization q7 the effect upon heat loss in discharged flue gas q2 the effect upon physical heat loss in ash and slag q6;the thermal efficiency of boiler is firstly enhancing and then reducing as the depth of desulphurization increases

this effect will be weakened as the direct escape rate of limestone increases;the affecting degree of desulphurization upon the boiler efficiency has close relationship with the coal sort and the limestone properties.