Co-combustion of sludge with coal is expected to improve the comprehensive combustion behavior of fuel,and promote reduction,harmless disposal,and resource utilization of sludge. Much study has been done on the combustion and co-combustion characteristics of sludge and coal,but the research on the occurrence of N and S in fuel and its effect on the release characteristic and control of pollutants during co-combustion is still insufficient. The co-combustion characteristics,interaction,and kinetic behavior of Xuzhou bituminous coal and municipal sewage sludge using a thermogravimetric analyzer coupled with a Fourier transform infrared spectrometer (TG-FTIR) were carried out. In addition,the occurrence of N and S elements in fuel and its thermal transformation behavior were studied. The results show that a significant interaction occurred during the co-combustion of Xuzhou bituminous coal and municipal sewage sludge at 300-750 ℃,improving the co-combustion performance. The ignition and burnout temperature decrease with the increasing proportion of municipal sewage sludge. The kinetic results show that the activation energy of the co-combustion process is between both of the single samples. The reaction mechanism of mixed combustion of a small amount of sludge is close to that of coal. In the sewage sludge sample,pyrrolic-N and quaternary nitrogen are the main N-containing species. A large amount of NH3 and HCN emission are released due to its decomposition. As for bituminous coal,pyrrolic-N is the main N-containing species,and its decomposition leads to the emission of NO and HCN. The N-containing gaseous release intensity during co-combustion is lower than that of coal or sewage sludge mono-combustion. Sulfone sulfur,and non-aromatic sulfur are the main S-containing species in sewage sludge. Meanwhile,organic sulfur in sewage sludge decomposes below 400 ℃,resulting in a large amount of SO2 released. The S-containing species exist in coal mainly as the formation of sulfate (66.24%) and pyrite (21.97%),thiophene sulfur (11.79%),which is contributed to the SO2 released at high temperature (350-650 ℃) due to the higher thermal stability of its sulfur compounds.