DEVELOPMENT AND EVALUATION OF BIO-DIGESTER TO PRODUCE BIO- ETHANOL FROM CASSAVA PEELS

Abstract

Energy consumption and global carbon have increased worldwide, reinvigorating worries about potential depletion of fossil fuel and scarcity of petroleum reserves. Such increase, accompanied by increment of geopolitical consequences in oil-producing regions and global warming due to the use of fossil fuels has motivated many countries to search for alternative forms of energy. Global warming significantly increases due to the use of fossil fuels in the form of oil, natural gas and coal, on which modern society depends. To this end, a mini reactor for bioethanol production was designed, fabricated and its performance evaluated. The mini bioethanol reactor was designed for the production of bioethanol from cassava slurry using the principle of fermentation and liquid-gas interaction inside a closed digester. Eight kilograms (8 kg) of cassava peels were collected from cassava processing sites within Akure and its environs. The methods used for bioethanol production includes; hydrolysis, fermentation and distillation process. The cassava peels were washed to remove dirt, dust and other impurities and sun-dried for three days to remove or extract moisture, and thereafter ground to flour. The flour was cooked to slurry to aid the enzymatic activity and poured into the digester. The effect of pH on digestion of cassava peels slurry was evaluated. The pH value for the first 10 days varied between the ranges of 3.5 – 4.6 and for the remaining days, the pH value varied between 2.7- 4.5 which is acidic. The highest pH (4.6) was recorded on day 11 with a corresponding volume of bioethanol of 295 mL. The highest temperature recorded was 27.9 o C and the volume of average bioethanol was 875 mL at day 30. Bioethanol production started from day 11 with average volume of 30 mL and the highest volume of bioethanol was produced on day 30 with average volume of 875 mL. The study concluded that bioethanol can be produced from cassava peels thereby converting waste to wealth.