Anaerobic digestion (AD) is considered an attractive agriwaste
management technique because the goals of pollution
control, energy recovery and nutrients recycle can be achieved simultaneously (Li et al., 2014). Of particular importance is its
application to the treatment of animal wastes where it can play a
significant role in minimising the uncontrolled emission of
methane to the atmosphere, thus reducing the impact of greenhouse
gases associated with livestock management. The microbiology
of the process relies on a number of interdependencies which
allow a variety of complex organic materials to be converted to
methane through the processes of hydrolysis, acidogenesis,
acetogenesis, hydrogenogenesis and methanogenesis (Demirel
and Scherer, 2008).