EVALUATION OF BIOGAS POTENTIALS OF Cymbopogon citratus AS ALTERNATIVE ENERGY IN NIGERIA

This research explored the potentials of Cymbopogon citratus (Lemon Grass) for biogas production as a cost effective alternative energy source in Nigeria. The Cymbopogon citratus was crushed to small sizes between 20 to 50mm and pre-fermented for 40 days in a PVC drum. Six (6) kg of the pre-fermented Cymbopogon citratus was mixed with water in ratio 1:1 w/v to form slurry and digested for 30 days. The floating drum gas collection system was used to collect the gas after it was passed through water and lime respectively for scrubbing. A total of 0.125m3 (6.95x10-4 m3/kg/day) and 0.0897m3 (4.98x10-4 m3/kg/day) of biogas was produced from the Cymbopogon citratus before and after scrubbing respectively. The gas produced was used for cooking test. The scrubbed gas had higher cooking rates for both water and rice respectively (0.12L/min and 0.0052L/min) while the cooking rates for unscrubbed gas were 0.079L/min and 0.0036L/min respectively. During this period, daily ambient temperatures of the research environment varied from 310C to 420C while the digester temperature fluctuated between 28oC and 36.70C. The pH of the medium fluctuated optimally between 6.5 and 7.8. The research demonstrated that Biogas could be produced from Cymbopogon citratus in quantity and quality comparative with those in literatures