Biogas Yielding Potential of Maize Chaff Inoculated with Cow Rumen and Its Characterization

Abstract

Human Life on earth is driven by energy and with the global challenge on best ways to manage waste, there is need to convert organic waste to bioenergy which will help reduce the rate of environmental pollution and over dependence on conventional source of energy. In this investigation maize chaff were inoculated with cow rumen using different concentration ratios (S/I) of 1:1, 1: 1.55, 1:3.5 for 25, 31 and 37 days Retention Time (RT) as design by Central Composite Face Centered Design to optimize the process and predict the best response. The result obtained shows that the mixture ratio of 0.65 (1:1.55) for 31 days gave the optimum yield while 0.65 mixing ratio for 37 days gave the maximum yield at 0.42L under mesophilic (20°C to 45°C) condition. The Flash point of the cummulative maximum yield was -164°C which is really flammable. The model F-value is 95.03, p-values is < 0.0001 which is less than 0.05 and both values indicate model terms are significant. Lack of Fit F-value of 0.43 implies the fitting effect is good. Its R2 value of 0.9855 is very close to 1 which is good. In addition, the biogas products were characterized by FTIR spectroscopy and Gas chromatography–mass spectrometry (GC-MS). The FTIR analyzes showed the presence of Alcohol and was further proven by 69% methane gotten as indicated by the GC-MS. Thus, the result shows high methane yield, flammability and suitability for maize chaff inoculated with cow rumen for energy production.