BIOGAS PRODUCTION FROM ANIMAL MANURE

An experimental study worked on a model biogas production unit which has 0.5 m3 fermentation tank capacities of a breeding farm in the Urla district of Izmir/Turkey. The farm animal quantity is 70 cattle and 1400 chicken. Animal wastes (poultry manure and bovine animals manure) were anaerobically fermented in the tank. It is known in literature, the optimum fermentation occurs at 298-313 K temperatures. In this respect, experimentation was performed at summer season and average regional temperature was 307 K and so reaction does not require the extra heating for the optimization of process. Biogas production potential from bovine animal and poultry manure was separately studied. Firstly, 350 kg bovine animal manure blend (175 kg manure+175 kg water) filled to the tank and the process occurred. Secondly, 375 kg poultry manure blend (50 kg manure+325 kg water) was filled to the tank and the processes done. Then the biogas production rates was evaluated and compared for two processes. Results showed that daily 6.33 m3 and 0.83 m3 biogas productions were obtained from fermentation of bovine animal manure and poultry animal manure. Lower heating value of natural gas was known 34,000 kJ/m3 , and biogas LHV value waspredicted 21,000 kJ/m3 by the 62% CH4 content. By using biogas as a fuel to the heating or energy systems instead of natural gas about 0.35 $/m3 energy cost is saved