Comparative evaluation of biogas production from Poultry droppings, Cow dung and Lemon grass

The study explored the production of biogas from Lemon grass, Cow dung and Poultry droppings. The three substrates were pre-fermented according to standard methods. Six (6) kg of each pre-fermented substrate was mixed with water in ratio 1: 1 v/v to form slurry and digested for 30 days. A total of 0.125 m(3), 0.191 m(3) and 0.211 m(3) of biogas were respectively produced from the Lemon grass, Cow dung and Poultry droppings with deviations of 0.00234 m(3), 0.00289 m(3) and 0.00484 m(3) respectively. The cooking test carried out revealed that the scrubbed gas had higher cooking rates for water (0.12 L/min, 0.085 L/min and 0.079 L/min for Lemon grass, Cow dung and Poultry droppings respectively) while the cooking rates for unscrubbed gas were 0.079 L/min, 0.064 L/min and 0.06 L/min respectively. The pH of the medium fluctuated optimally between 6.5 and 7.8. The research demonstrated that Lemon grass produced less volume but better quality biogas compared to Cow dung and Poultry droppings. (C) 2014 Elsevier Ltd. All rights reserved.