Valorization techniques for biomass waste in energy Generation: A systematic review

The valorization of biomass waste into energy through thermal (i.e., gasification, pyrolysis), biological (i.e., anaerobic digestion) processes, and hybrid systems has garnered substantial attention due to its potential environmental, economic, and energy efficiency benefits. This systematic review aimed to provide a comprehensive analysis of various biomass waste valorization techniques for energy generation. Systematic searching in various databases and four key organizational websites yielded 317 relevant studies, of which 78 were selected according to the inclusion criteria. The review reveals the promise of techniques such as pyrolysis, gasification, anaerobic digestion, and hybrid systems for energy generation from biomass waste, while also emphasizing the influence of factors such as feedstock composition, process conditions, and energy conversion efficiency on their effectiveness. The capital investment requirement and payback period are presented in a detailed cost analysis as differing widely, from $3 million for fermentation to $10 million for incineration, with payback periods ranging from 4 to 8 years. The critique delineates technical challenges, such as feedstock heterogeneity and process optimization, and emphasizes the need for development in pre-processing, technological improvement, and integration with current energy infrastructures. The conclusions offer insightful information on the process efficiency, energy yield, and environmental sustainability of biomass valorization processes, thereby informing further research, policy-making, and industrial applications in sustainable energy generation.