Colombian agroindustrial crop residues: Thermochemical characterization and evaluation of their energy potential

Abstract

Agricultural waste has been identified as a possible reservoir for generating valuable products and energy sources. However, its diverse and non-standard composition poses challenges to maximizing its potential in product generation. This study aims to characterize Colombian agroindustrial crop residues, such as cocoa pod husk (CPH), cocoa bean shell (CBS), sugar cane bagasse (SCB), and plantain leaves (PL), as sustainable and reliable sources and feedstocks for conversion processes, given their high production in the country. Proximate, ultimate, and biochemical compositions, energy content, and thermogravimetric analysis were performed on the biomass samples. The results showed that thermochemical processes can be applied to dried CPH, however, its high moisture content upon harvesting makes it more suitable for biochemical treatment despite its high lignin content. CBS naturally attains brittleness and dryness, making it a good candidate for use in densification processes, e.g., pellets. However, CBS's elevated nitrogen content suggests its use in co-combustion. The characteristics of SCB make it ideal for cellulosic ethanol generation, considering SCB's high availability in the country and the successful implementation of ethanol technology in the region. Upon harvest, PL has high moisture and inorganic content. Through hydrothermal treatment, PL can be converted into hydrochar with increased hydrophobicity and reduced inorganic content. This research promotes the advancement of environmentally sustainable bioenergy solutions in Colombia. By utilizing these abundant agricultural residues, Colombia stands to realize the potential for a sustainable, carbon-neutral energy source, while improving waste management practices, and fostering economic growth within the agricultural sector.