Gasification of biofuels blended from olive mill solid wastes and pine sawdust under different carbon dioxide/nitrogen atmospheres

Abstract

In this paper, we investigated the gasification of charcoals using a macro TG under CO2 mixed with nitrogen at different percentages (40%, 70% and 100% CO2) and at different fixed temperatures (750 °C, 800 °C, and 900 °C). For this purpose, two raw residues were selected; the exhausted olive mill solid wastes (EOMSW) and the pine sawdust (PS). Then, four different samples, which have not been previously studied with a gasification process, were prepared from these residues when investigating the impregnated and the non-impregnated ones using the olive mill waste water (OMWW) as by-product for the impregnation process. Moreover, a comparison between results obtained during this study and those obtained during a previous study based on steam gasification was carried out. It was found that the mass loss profiles are consistent with the usual lignocellulosic gasification behaviors. Also, the increase of temperatures or CO2 percentages affects positively the conversion, the gasification rate and the char reactivity. It is worth noting that CO2 acts differently from steam. With steam, gasification is found to be faster and more reactive.