Enhancing methane yield from duck waste by co-digestion with Xyris capensis

Department of Mechanical Engineering Science, Faculty of Engineering and Built Environment, University of Johannesburg, South Africa.

^* Corresponding author: olaoladoke293@gmail.com

Abstract

This study examined the possibilities of enhancing methane yield from anaerobic digestion of Xyris capensis and duck wastes based on improved feeding composition and the C/N ratio. Batch anaerobic digestion of Xyris capensis and duck wastes was conducted at mesophilic temperature (37 ± 2 °C) with the mixing ratios of 100:0, 75:25, 50:50, 25:75, and 0:100% of duck wastes: Xyris capensis. The highest methane yield of 301.17 mL CH₄/ gVS_added was recorded when the mixing ratio of 50:50% (duck wastes: Xyris capensis) and C/N ratio of 19.26 was digested. The biodegradability (BD) of duck wastes and Xyris capensis were 86.60 and 58.57%, respectively. The BD of duck wastes increases with the addition of Xyris capensis, and it started to decline after a 50:50% mixing ratio. A stronger synergistic influence of co-digestion was noticed compared to monodigestion of the individual of each feedstock. This study showed a better performance of anaerobic co-digestion and can be used to enhance feeding composition and the C/N ratio. In general, methane production from duck wastes co-digested with Xyris capensis is a good strategy to generate renewable energy and minimize waste management challenges.