Combustion kinetics and emission characteristics of peat by using TG-FTIR technique

Smoldering combustion of peat receives considerable attention for the substantial destruction of carbon storage and potential health threats from high yields of noxious gaseous products. In this work, the combustion characteristics of peat were investigated by using thermogravimetric analysis coupled with Fourier transform infrared spectrometry (TG-FTIR) at five heating rates (5, 10, 15, 20 and 30 K min(-1)). The results showed that the combustion process included three stages, corresponding to the processes of dehydration (302-423 K), decomposition of organic matters of peat (423-643 K) and char oxidation (643-873 K). Tiny light organic gas products were generated in a lower temperature range (473-643 K), primarily ascribing to the decomposition of organic matters. Abundant CO2 and slight CO were released in a higher temperature range (643-873 K) during the combustion process, mainly due to char oxidation. A four-step kinetic scheme was developed through Genetic Algorithm and described the combustion kinetics very well. These results provide a better insight into the smoldering combustion characteristics and the gas emission behaviors of peat.