Effect of digester surface area on biogas yield


  • Gbolabo Abidemi Ogunwande Obafemi Awolowo University, Nigeria


biogas yield, digester surface area, poultry manure, swine manure, cow dung


Poultry manure, cow dung and swine manure were digested in cube-shaped anaerobic digesters of equal volume but different surface areas (SAs) (5.38, 10.0 and 11.6 dm2) in a two-factor experiment. The digesters were agitated once a day during the experiment. The results showed that neither the manure type nor SA affected (p > 0.05) substrate temperature and pH, but both had (p ≤ 0.05) on biogas yield (BY. Poultry manure had the highest BY followed by swine manure and cow dung (1.00, 0.59 and 0.11 dm3 kg-1 VS fed day-1, respectively). Within the SAs investigated, BY increased as digester SA increased (0.27, 0.68 and 0.74 dm3 kg-1 VS fed day-1 for 5.38, 10.0 and 11.6 dm2, respectively). The results of the regression analysis showed that digester diameter to substrate height ratio and BY had a polynomial relationship with a dome-shaped curve, indicating that BY would not keep increasing exponentially with increase in digester SA at the expense of substrate height.

Author Biography

Gbolabo Abidemi Ogunwande, Obafemi Awolowo University, Nigeria

Dept. of Agricultural and Environmental Engineering; Senior Lecturer.






IV-Energy in Agriculture