The co-combustion characteristics of a bituminous coal mixed with two kinds of dry sludge(hot air dried and microwave irradiation dried)with different blending ratios were investigated through thermogravimetric analysis.The results show that

there's great difference between the combustion characteristics of the sludge and that of the coal.The sludge and coal had a combination effect on the co-combustion performance.The maximum flammability index and comprehensive combustion characteristic coefficient appeared when the sludge proportion in the mixture was 40%.The separate combustion characteristics of the sludge dried by above two methods were nearly the same

and were also similar to the co-combustion performance of their mixture with the coal.The release and burning stage of the volatile matter played a key role in sludge combustion.The combustion mechanism functions of the above two sludge were the same.