In order to understand the regularity of mercury emission from coal-fired power plant and influence of conventional pollutant control facility upon the mercury emission control

test and research about mercury emission and its control for boiler of one 300 MW unit have been carried out by using the Ontario-Hydro method(OH method)and the continuous emission monitor method(CEM method).Results of test shows that the mercury emission is mainly in gas state

and there is very little mercury in the bottom slags.The electrostatic precipitaror(EP)has certain control effect

the total mercury ration in flue gas after passing through the EP has been somewhat reduced

the mercury particles have been eliminated 49.2% by the EP.Comparing result of test using CEM method with that of test using OH method

it has been discovered that the test accuracy of two said methods for total mercury in gas state all is better

the measurement deviation of single substance mercury and gas state mercury being not large.