The feed materials were a batch of cow dung and rice husk.
The cow dung was sourced locally from cow farms, and the
rice husk from Abakaliki Rice Mill Industry, Ebonyi State,
Nigeria. The cow dung from N'dama species was used
because of its availability compared to other species in the
study area. Fig. 1 gives a picture of a typical rice husk hill
from Abakaliki rice mill industry. The digester feed included a
batch of cow dung and rice husk. Each of these was dried
using open sun-baking and then carefully stored in a stoppered
polyethylene container. In order to ensure efficient
stabilisation of the wastes during anaerobic digestion,
innoculum obtained from the rumen of cows slaughtered at
Abakaliki main market abattoir was used. The
micro-organisms were maintained in an anaerobic
environment by straining the innoculum in cheesecloth and
then stored in an airtight container. The tip of the digesters was
sealed off with clip/cello-tape in order to maintain complete
anaerobic condition during the anaerobic digestion for the cow
dung and rice husk respectively.