Track: Environmental Engineering

Abstract

The aim of the study is to exploit the potential of mud beyond its current applications in construction industries, to insulate bio-digesters against temperature fluctuations. To achieve this, six identical fixed dome biogas digesters (32 Liters) were designed, constructed and used to carryout anaerobic digestion of three feedstocks namely cow abdominal waste, poultry droppings and 1:1 mixture of cow abdominal waste and poultry droppings. Three digesters were charged and surface covered with mud for insulation while the remaining three were charged and kept on the surface uninsulated. The ANOVA result indicates that Mud insulation of digester and feedstock have significant effect on the performance of the fixed dome biogas digesters (α =.0.05). The range of pH, Volume of biogas and slurry temperature (ST) in all the feedstocks (Cow abdominal waste, poultry droppings and 1:1 mixture of Cow abdominal waste and poultry droppings) were 6.948-7.170, 3.643-3.865 liters and 29.917-30.242oC, respectively. The highest volume of biogas was produced by mud insulated surface fixed dome biogas digester with cow abdominal waste feedstock. The highest temperature evolution was from 1:1 Mixture of Cow Abdominal Waste and poultry droppings feedstock.