SUMMARY
The biogas production from the agricultural wastes is accepted as an eco-friendly solution for keep up with increasing energy demand in the world. The cow manure which is produced in every farm is readily available source for biogas production via anaerobic digestion. The main limitation for biogas production from manure is the inhibition of anaerobic microorganisms resulted from the high ammonia/ammonium content of manure. The co-digestion of manure with agricultural wastes is frequently applied to cope with this limitation. This study aims to investigate the biogas production from the co-digestion of cow manure and greenhouse residues in different mixing ratios as input materials. Tomato and pepper wastes from greenhouses were selected as co-substrates and optimum mixing ratios for maximum biogas yield from co-digestion of cow manure with tomato and pepper wastes were determined as 55:45 and 25:75, respectively. Along with the biogas production, co-digestion kinetics were also evaluated for biogas production from cow manure and tomato with the help of well known mathematical models. The results indicated that the co-digestion of cow manure with greenhouse wastes is viable option for the biogas production.