Abstract:
Biogas is an alternative and renewable energy source produced through anaerobic digestion of
organic matter. The aim of this study was to obtain the optimal mix ratio for biogas
production from anaerobic digestion of Parthenium weed and goat manure. The experiment was
batch operated and daily gas yield from the plant was monitored for 30 days. The Parameters
studied were total solids (TS), volatile solids (VS), fixed solids, organic carbon, and moisture
content. For the experimental design, different mix ratios were adopted for the five digesters
employed. In this case, for the first digester, 100%goat manure was used. For the 2nd digester
75%goat manure and 25 % parthenium weed were used. The 3rd digester was filled with goat
manure and parthenium weed in 1:1 ratio. The 4th digester contained 25%goat manure and
75%parthenium weed. The last digester contained only parthenium weed. The gas production
rate was measured on daily basis using water displacement method. Gas production was noticed
in all of the substrates types from the second and third day of digestion and went to zero at about
28 days in all digesters. The experimental data shows a greatest gas output of 572.5ml of gas
production in the mix ratio of 75%goat manure and 25%parthenium weed, suggesting mix ratio
of the two substrates is an optimal mix to yield the highest biogas production. All measured TS,
VS, pH organic carbon and moisture content were significantly varied between before and after
AD. Overall results indicate that the biogas yield and Volatile solid and Total solid reduction
can be significantly enhanced when goat manure and parthenium weed are co digested in
75%goat manure and 25%parthenium weed mix ratio.
