Abstract

Biodegradation with heterogeneous catalysts were successfully carried out in the production of biogas from wheat wastes, rice husk and spent grains. Five digesters were charged with spent grains/clay soil, spent grains/lime stone, rice husk/clay soil, rice husk/lime stone and wheat wastes/potash, respectively. Clay soil, limestone and potash were used as catalysts for optimizing and to speed up the chemical reactions in the digestions. The total viable count, total mold count, structural absorbance and transmittance, and micrograph of the wastes were carried on the waste samples. The digestions were carried out for a period of sixty (60) days. Results showed that spent grain/clay soil set-up produced combustible biogas on the 4th day with total cumulative biogas of 69.3 L, followed by wheat wastes/potash which produced combustible biogas on the 34th day with total cumulative biogas of 178.5 L. Proximate analysis was performed on the gas samples, showing the presence nitrogen, phosphorous and potassium (NPK). Characterizations using combustion analyzer showed that methane content of Exp.A and Exp.E were 75.6 and 81.7%.

Key words: Optimizing, catalyst, combustible, transmittance, micrograph.