The combustion characteristics of semi char made from Xilinhaote lignite were experimentally studied in a cyclone chamber in lean oxygen atmosphere.The influencing factors such as excess air coefficient and burning load were studied.The results show that

the calorific value of the combustion products was 1.5 MJ/m3 to 3.5MJ/m3 with excess air coefficient from 0.5to 0.9

and it decreased with the increasing excess air coefficient.The carbon conversion of the semi char increased with the excess air coefficient

it reached up to 97% when the excess air coefficient was higher than 0.6.The temperature at main burning zone rose with the excess air coefficient

it reached 1 280 ℃ when the excess air coefficient was 0.7

which was higher than the fluid temperature of the semi char ash

this can ensure the liquid slag discharge.The feeding rate had little influence on combustion characteristics of the semi char

indicating the cyclone chamber had a good performance of load regulation.Under lean oxygen conditions

the NO emission from cyclone combustor was low and it increased with both the excess air coefficient and the char feeding rate.