Influential factors in anaerobic digestion of rice-derived food waste and animal manure: A comprehensive review.

Utilization of organic community wastes towards deriving sustainable renewable energy and adequate disposal of the residual has been an important topic of investigation. Anaerobic digestion and co-digestion of rice-derived food waste and animal manure for sustainable biogas generation is crucial from the view-point of community consumption. This paper presents an extensive review of the important and recent contributions in the related areas. The critical physico-chemical parameters involved in such digestion process are analyzed, including temperature, carbon-nitrogen ratio, microorganisms, pH, substrate characteristics, organic loading rate, hydraulic retention time, volatile fatty acids, ammonia, and light/heavy metal ions. Studies implied that the optimum yield of biogas production could be achieved only when the values of the parameters exist in the specific ranges. Few recent studies highlighted the use of emerging techniques including micro-aerobic system, additives, laser radiation, bio-electrochemical field, among others for efficiency enhancement of the digestion process and optimum yield. The entire study provided a set of important conclusions and future research directives are as well proposed.