Influence of Secondary Reactions on the Heat of Pyrolysis of Biomass

Abstract

The thermal behaviors during the pyrolysis of two different biomass samples, beech wood from carpentry residuals and artichoke thistle from energy-dedicated crops, were investigated. Thermogravimetry/differential scanning calorimetry (TG-DSC) and thermogravimetry coupled to Fourier transform infrared (TG-FTIR) analysis of evolving products were used to investigate the thermal effects of the pyrolysis process. The role of pretreatments (hot-water washing, ethanol extraction, and their combination) was also analyzed. High alterations in the heat demand were observed as a function of the initial sample mass and pyrolysis conditions. The role of vapor-solid secondary interactions was evidenced by the evolution profiles of the main pyrolysis products.

Study on the Biochar Yield and Heat Required during Pyrolysis of Two-Phase Olive Mill Waste

“…Both increasing the initial mass of the TPOMW sample and covering the crucible result in a significant increase of charcoal yield. This finding is consistent with literature data (e.g., the published studies of Goḿez et al 23 and Rath et al 22 ) and can be explained by the enhancement of secondary reactions between the primary volatiles and the solid residue. If this fact is assumed to be true, it seems reasonable to suggest that high charcoal yields might be associated with low values of the apparent heat.…”

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