CHARACTERIZATION OF SOME ANIMAL RESIDUES AS POTENTIAL ALTERNATIVES TO FOSSIL FUELS AND SOIL AMENDMENTS

The aim of this study is to perform a comparative study on some selected animal residues in
order to explore their potential as alternative sources of energy and soil amendments.
Agricultural residues are potential deposits and reservoir of energy vectors that could be used as
renewable energy sources if harnessed for economic purposes. Average annual livestock residue
in Nigeria was estimated at 105,007 Mt most of which were left without meaningful and
appreciable economic viable management policy. The multiplication of livestock farming and
aggravated accumulation of crop residues after harvest stimulates increased emission of
greenhouse gases during decomposition and burning thereby encouraging rise in average global
temperatures and increased greenhouse effect. Four livestock residues wastes were evaluated for
their yield potentials of CH4, CO2, and N2Oat an ambient temperature (28OC). Both physical and
chemical compositions of the residues were determined using standard laboratory procedures
after drying at 77OC. Percent by mass (Pm), molar compositions (Mc); molar ratios (Mr.), air
requirements for oxidation (Ar), chemical formulae (Cf), energy content (Ec) and potential
volume of methane (Pv) available for harvest were evaluated using empirical models. Results
obtained showed that poultry manure has the highest percentage of CH4 (15.51%); pig has the
highest percentage of CO2 (16.62%); the N obtained for all the manures were similar, while the
N2O was insignificant to make any meaningful difference. The results also shows that, horse
manure has the highest percentage of 8.03% K while the amount of N, and P are similar for all
the manures tested, suggesting suitable alternative composting sources for soil amendment.
Overall result shows that poultry manure has the best potential energy value of 45.852 Kj/Kg.