Evaluation Of Higher Heating Value Correlations for Lignocellulosic Biomass and Biochars Obtained Through Slow Pyrolysis

Abstract

This work consists of the economic and environmental valorization of agricultural residues and by-products through a thermochemical conversion process for the production of renewable solid fuels. In this context, slow pyrolysis appears as an excellent sustainable alternative for the reuse of all material that would normally be discarded with no economic value, in comparison of deforestation for the production of charcoal and the industrial activities of coal. Thus, the physical and chemical characteristics of the materials involved were analyzed using techniques such as ultimate and proximate analysis. From these characterizations, lignocellulosic biomasses (bocaiuva seed cake, crambe seed and licuri nutshell) and their respective biochars had their energy potential predicted according to several correlations. Due to the existence of a wide range of formulas in the literature, a comparative assessment of the parameters involved in these equations was performed. Thus, it was stipulated that the formulas proposed by Parikh and Nhuchhen would be more suitable for the type of material in this work, thus managing to predict a higher heating value (HHV) closer to the empirical result from a calorimeter. The results of HHV showed that licuri and its respective biochar have a great potential to fit the market for solid renewable fuels, since the values ​​obtained were higher than reference combustible materials (charcoal and coal). In addition, based on the yield data of licuri fruits and residues and the yield of pyrolysis, a basic projection of the large-scale biochar production becomes possible through slow pyrolysis.