Abstract:
Biogas is the methane rich gas produced by anaerobic breakdown of organic wastes with the
help of methanogenic bacteria under oxygen free environment. The objective of this study was to
evaluate production of biogas from co-digestion of goat manure and sludges of beer under
anaerobic condition. The three containers were interconnected with a plastic tube having a
diameter of 1 cm. The acidified brime solution was prepared by dissolving NaCl in distilled
water with few drops of sulfuric acid until a supersaturated solution was formed to prevent the
dissolution of biogas in the water. The tube connecting the first bottle to the second was fitted
just above the slurry in the first bottle to help gas collection In five mix ratios under mesophilic
conditions (380C) using a batch digeters for 30 days.. In all treatments physico-chemical
parameters such as total solid, volatile solid, organic carbon, nitrogen, and pH values were
measured before and after anaerobic digestion. All measured physico-chemical parameters of
each substrate were siginificantly varied between before and after AnaerobicDigetion p<0.05.
Comparison of pH values between before and after anaerobic digestion showed that pH values
were siginificantly increased after anaerobic digestion for all treatments. Maximum reduction in
%Organic Carbon, total solid and volatile solid were observed in 75%Goat Manure and
25%Sludge Bree mix ratio. Assessment of cumulative biogas production showed that substrate in
a mix ratio of 25%Sludg Bree+75%Goat Manure showed the highest biogas yield, and this
corresponded to the extent of reduction in %Organic Carbon, total solid and volatile solid after
AnaerobicDigetion. In conclusion the result of this study indicate that the increase in biogas
yield and reduction in volatile solids and total solids can be siginificantly enhanced when goat
manure is co-digested with sludge of beer in 25%SludgBree+75%Goat Manure. Since this
experiment was carried out on the co-digestion of goat manure and sludge of beer, further
similar studies are recommended on co-digestion of goat manure with other substrates.
