Experimental Results and Parametric Analysis of Wood, Torrefied and Coffee Grounds Pellets Gasification Carried Out on a Pilot Plant Reactor

The purpose of the present study consists in presenting the results of an extended experimental gasification campaign involving the utilization of woody biomass as raw material, torrefied biomass as representative of upgraded lignocellulosic feedstocks and coffee grounds as example of food residue. These activities have been carried out on a lab-scale batch gasifier suitable developed for this study. This experimental approach has been specifically oriented to evaluate the impact of the air flow rate, used in this case as gasification agent, on the main parameters of the process as: the productivity of the syngas and its heating value, the amount of the remaining char, the power of the gasifier and the cold efficiency of the process. As relevant results, this study demonstrates that the optimal performances of the process can be achieved in correspondence to a restricted variability range of the air flow rate that assumes the role of controlling parameter specifically target for each one of the investigated type of biomass.