Anaerobic digestion of lignocellulosic waste using alkali pretreatment method interms of performance, microbial community, and cost analysis

Abstract

Agricultural residues with lignocellulosic structures play a crucial role among renewable bioenergy sources and are abundantly available in nature. Anaerobic digestion (AD) is considered an ideal technology for agricultural waste stabilization/treatment and the production of renewable energy carriers. However, the overall economic value of the produced methane remains low, especially when compared to the potential value of waste streams. In this project, the aim is to facilitate the transition to anaerobic fermentation using agricultural waste, specifically sunflower stalks and heads with lignocellulosic structures, to increase the production of volatile fatty acids (VFA). An alkali pretreatment method will be employed as a chemical pretreatment process to investigate the yield from the selected agricultural waste and assess its impact on acidification efficiency. The purpose of using a pretreatment process is to make lignocellulosic material which is difficult to biologically degrade, more easily digestible thereby enhancing process efficiency. Wastes subjected to pretreatment with Potassium Hydroxide (KOH) at various dosages will be thoroughly examined for VFA yield. During the research process, the taxonomic classification of the microbial community active throughout the process will be conducted using the third-generation sequencing technology provided by Oxford Nanopore MinION, targeting the 16S and 18S rRNA gene regions. Finally, a cost analysis will be developed based on the obtained data. This analysis aims to contribute significantly to research in this field by providing practical guidelines to enhance the effectiveness of anaerobic treatment systems and transform organic waste into a sustainable energy source