SEMI-CONTINUOUS ANAEROBIC CO-DIGESTION OF COW MANURE AND BANANA WASTE: EFFECTS OF MIXTURE RATIO

Anaerobic co-digestion of cow manure (CM) and banana waste (BW) was investigated.The experiments have been carried out and were tested for different mixture ratios of CM:BW in terms of volatile solids : 100:0, 80:20, 60:40, 50:50, 40:60, 20:80 and 0:100 with the aim to maximize methane yield and methane production from the anaerobic co-digestion of cow manure and banana waste.The results obtained show that a maximum methane yield of 229 mL STP /g VS added was obtained at a (CM): (BW) ratio of was 40:60 with a biodegradability of 86% for an organic loading rate in the range of 1.49-3.57kg waste mixture/(m 3 d).The pH and alkalinity for all experiments were controlled and kept within an optimum interval of 7.1-7.6 for pH and 2-4 g CaCO 3 /L for alkalinity.It was shown that banana waste and cow manure could easily be degraded by anaerobic co-digestion under mesophilic conditions, resulting in methane yields sufficient for commercial production of methane.