Abstract:
Food waste (FW) getting changed into biogas not only becomes an alternative resource of
energy but also helps in reducing the methane fabrication which is one of the green house
gases that cause global warming. In this research the estimation of FW generation rate is the
initial steps work when considering the energy recover through the Anaerobic Digestion (AD)
method. The aim of this study is to investigate the recoverable potential of electric energy
from FW. FW is obtained from Jimma University student cafeteria and specialized hospital. Two fabricated laboratory-scale digesters were used to digest the FW with different
concentration of moisture (H2O) content and also by adding inoculates as a microbial sources
and catalyst by using AD technology through batch reactor process systems and mesophilic
type temperature conditions Experimental analysis was conducted. The water displacement
method was used to investigate the volume of biogas produced and methane gas identification
was done through biogas analyzer machine. The total production rate of biogas was found to
be 260.18ml/225g of waste within 70% of H2O content in a day, which was produced large
biogas whereas it was 188.9 ml/150g with an average production rate in a day with 80% of
H2O content and it was less biogas production. In general, the study was estimate FW
generation rate from Jimma University which account to 2.036tonns/day and
752.558tonnes/year. Biogas production from FW through an AD of 5L capacity digester in
the lab scale was evaluated for 23 days. The total amount of biogas production recorded was
about 2463ml (58.16% CH4) in reactor1 and 2266.5ml(55.07%CH4) in reactor 2 which can
recover 0.053kwh/day( i.e 19.4kwh/year) and 0.0043kwh/day (i.e. 1.57kwh/year) electrical
energy respectively. Based on this we can recover electrical potential energy which accounts
to 17677.89kwh/d and 6452428.35kwh/y from752.558tones/y FW. Finally it recommend that
large FW generation disposed to land fill can be converted to biogas through mono-AD
process as alternative sources of electrical potential energy recoverable which can reduce
scarcity of electrical energy supply and LPG costs, which is mandatory to sustainable
development of social, economical and environmental feasibility.
