Kinetic Study on Continuous Sampling of Coal Char from a Micro Fluidized Bed.

We self-design a micro fluidized bed reactor (MFB) with combination of an online char particle sampling system to study the kinetics of coal char combustion and gasification. The system mainly contains two parts: a micro fluidized bed and vacuum online sampling. Vientiane coal was continuously sampled from the MFB. Both combustion and gasification reactivities of the sampled chars were tested in a thermogravimetric analyzer. Kinetic parameters of the sampled char were analyzed. Char reactivity in oxy-fuel combustion in the MFB obeys the rule of decrease-increase-decrease behavior with the sampling time. Pre-exponential factor and activation energy of the sampled char increase with the sampling time. The gasification reactivity of the sampled char increases with the sampling time even though there is a minor decrease in an initial gasification stage. The new designed MFB combining with the online sampling system will pave the path for the investigation of gas-solid reaction evolution in the future.