Based on practically measured data from several boilers

the real fouling coefficient of different coal quality and of different heating surfaces

as well as real heat transfer coefficient of various heating surfaces have been calculated. Results of calculation show that the influence of different coal quality upon fouling coefficient of the heating surface has comparatively large difference

and affecting more obviously upon the operation performance of boilers. The listed influences of coal quality upon fouling coefficient of heating surfaces have comparatively large difference with recommended values in some standards currently in effect at abroad

needing to accumulate data from boiler test

design

and operation for correcting the said influences.