Effects Of Initial PH And Substrate Properties On Biogas Production Yield From Fresh Cattle Cud

ABSTRACT

 In this work, the effects of initial pH and substrate properties on biogas production yield from cattle cud for the production of biogas were anaerobically studied. The study was carried over 30 day's period at a room temperature. 1 00g of substrate (cattle cud) was reconstituted to various pH (3.5, 4.5, 5.5, 6. and 7.5) in laboratory sized, air tight (anaerobic) digesters. Biogas yield was monitored by downward displacement of water as a function of substrate properties, and thereafter characterized before and after use. The characteristics properties; pH, volatile matter, moisture, carbon to nitrogen ratio, ash and conductivity significantly varied before and after use. The cumulative highest yield of biogas was obtained at pH 3.5 with the yield standing at 929.6cm3. This was followed by the pH value of 4.5 with the yield of 714.70cm3, while the lowest yield was obtained at pH 5.5 with the volume of 7.5cm3. Result obtained generally indicated that the pH was an important factor that should be considered during anaerobic digestion.