Biogas Production from Anaerobic Digestion of Phragmites australis : Influence of Grinding Process, Harvesting Season and Co-digestion with Food Waste

Al-Iraqi, A.R. and Gandhi, B.P. and Folkard, A.M. and Barker, P.A. and Semple, K.T. (2025) Biogas Production from Anaerobic Digestion of Phragmites australis : Influence of Grinding Process, Harvesting Season and Co-digestion with Food Waste. Waste and Biomass Valorization. ISSN 1877-2641

Abstract

This study investigated the effect of harvesting time and using the co-digestion strategy on the digestibility of Phragmites australis biomass and methane production. The P. australis biomass harvested from summer, autumn, and winter was digested singly (mono-digestion) and combined with synthetic food waste (co-digestion) at an inoculum to substrate ratio 1:1 based on the volatile solid content of inoculum and substrate and under mesophilic conditions (37 ± 1 °C). The results found that cumulative methane production was low during mono-digestion of summer, autumn, and winter P. australis (36.26 ± 4.48, 35.59 ± 3.08, and 34.90 ± 4.40 mL/g VS added, respectively) due to the effect of lignin on the biodigestibility of P. australis. This issue was addressed by co-digestion of P. australis biomass from these three seasons with synthetic food waste, which resulted in an increase in cumulative methane production (135.66 ± 1.14, 137.33 ± 3.21, and 123.94 ± 1.01 mL/g VS added, respectively).