Processing of Agricultural Residues with a High Concentration of Structural Carbohydrates into Biogas Using Selective Biological Products

Abstract

Biomass, particularly agricultural residues and biomass rich in structural carbohydrates, offers significant potential for sustainable biogas production. Biological pretreatment using microorganisms, particularly Trichoderma species, is discussed as a cost-effective and environmentally sustainable approach to improving the decomposition of structural carbohydrates into fermentable sugars. This study aimed to assess the impact of employing a selective biological product (BP) on the biogas production process and biomethane potential using winter wheat straw (WWS) as a representative feedstock. The biological product, consisting of microorganisms of the Trichoderma spp. genus, was introduced to enhance microbial activity. The biogas potential results showed that WWS treated with the BP exhibited a remarkable improvement in biogas production. Specifically, biogas yield increased from 364.1 L/kg of mass in untreated straw to 439.9 L/kg in BP-treated straw, representing a substantial 20.8% increase. Furthermore, in continuous loading tests, the steady-state biogas yield from BP-treated straw ranged from 553.6 to 582.0 L/kg VS, which was notably higher compared to untreated straw with a yield of 490.0 L/kg VS. Overall, the results of this study demonstrated that the application of selective biological products significantly enhanced biogas production and biomethane potential from structural carbohydrates containing biomass sources.