Study on combustion and emission characteristics of chars from low-temperature and fast pyrolysis of coals with TG-MS

To achieve the clean and efficient utilization of low-rank coal, the combustion and pollutant emission characteristics of chars from low-temperature and fast pyrolysis in a horizontal tube furnace were investigated in a TG-MS analyzer. According to the results, the combustion characteristic of chars was poorer than its parent coals. The temperature range of gaseous product release had a good agreement with that of TGA weight loss. Gaseous products of samples with high content of volatile were released earlier. The NO and NO2 emissions of chars were lower than their parent coals. Coals of high rank (anthracite and sub-bituminous) released more NO and NO2 than low rank coals of lignite, so were chars from coals of different ranks. SO2 emissions of char samples were lower than parent coals and did not show obvious relationship with coal ranks.