Abstract
A 4000 L bio-digester was designed and fabricated using 5 mm mild steel plate with the main purpose of generating biogas and bio-fertiliser for Auchi Polytechnic Demonstration Farm. To achieve this, a varying ratio of 1.155 m3: 2.310 m3 mixtures of cow dung and water were anaerobically digested in the batch digester. The experiment lasted for 33 days during which the quantity of gas generated were evaluated. The volume of daily methane gas production ranged from 0 to 1.2 m3. The total volume of gas generated from the digestion was 21.68 m3 and comprised of 58% CH4, 25% CO2, 15% H2S and 2% other impurities. The results of physiochemical properties of the feedstock revealed a progressive increase of 6.0-6.2 in pH value from Day 4 after which it dropped sharply in value to 5.5 on the second week of fermentation. The minimum and maximum ambient temperatures of 24 and 30°C were observed while the slurry temperatures varied from 27 to 35°C. The average pressure built up of the digester was about 214,000 N/m2. The results further showed that biogas production is sensitive to pH and cannot produce optimally below the pH of 6.5. To achieve optimum biogas generation, a temperature range within mesophilic condition of 25 to 40°C and pH values of 7 should be maintained. Key words: Biogas, mesophilic temperature, retention period, anaerobic digestion, digester.  
Highlights
Nigeria is endowed with a lot of natural resources which comprises fossil fuel e.g. natural gas and coal that is, for power generation and other enormous purposes
It is evident from the study that the total volume of gas generated from the digestion was 21.68 m3 and comprised of 58% CH4, 25% CO2, 15% H2S and 2% other impurities
The optimal efficiency of anaerobic digestion and gas production depend on the intensity of bacterial activity, which is influenced by several factors such as ambient temperature, temperature of digester material, loading rate, hydraulic retention time and pH value of digester content
Summary
Nigeria is endowed with a lot of natural resources which comprises fossil fuel e.g. natural gas and coal that is, (petroleum) for power generation and other enormous purposes. Nigerian government over the years have applied different technical approaches and as well invested huge amount of monies in the energy sector but substantial progress in solving the energy crisis in the country is yet to be made. Unlike other developed countries of the world, provision of adequate energy to her citizen is not a major problem. The major challenge is on how to harness the energy source which is environmental friendly and ecologically balanced. This need has forced the world to search for other alternative sources of energy since the energy sources like the solar, hydro, wind etc. Require huge economical investment and technical power to operate, which is very difficult for the developing country like Nigeria This need has forced the world to search for other alternative sources of energy since the energy sources like the solar, hydro, wind etc. require huge economical investment and technical power to operate, which is very difficult for the developing country like Nigeria
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have