Prospective of pretreatment and anaerobic digestion of dairy cow manure in Fiji

Abstract

The continuing increase in dairy cattle farming poses a significant threat to the environment due to the release of greenhouse gases (GHG) from uncontrolled manure generation. Waste valorisation of dairy cow manure (DCM) through anaerobic digestion (AD) provides an avenue for simultaneously managing DCM and mitigating climate change through renewable energy. This review provides an overview of DCM production and the potential use of the AD processes for waste management and renewable energy generation in Fiji. Fiji dairy farms are geographically unevenly distributed and have considerably small herd sizes. With pretreatment techniques, biogas production from DCM at these farms has the potential to be optimised, economically feasible, and viable. Biogas production from DCM can be enhanced by approximately 125% with pretreatment techniques. Hence, this study reviews various pretreatment methods, their economic and environmental benefits, and AD's general challenges and limitations. This research reveals a need for further investigation into the optimisation of biogas and bio-methane potential of DCM, specifically with the economic viability and the environmental considerations of implementing these techniques at Fijian dairy farms. © 2023 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).