Among the other solutions planned to regulate these
problems, we can quote anaerobic digestion or the methanisation
of organic wastes in general and wastewater treatment
plant sludge in particular. The anaerobic digestion is an
organic matter transformation process in energy by bacteria
in oxygen absence. It permits to produce a combustible gas
called biogas, which is essentially methane composed, and
can reduce half of organic matter (Poh et Chong) [4]. The final
digestion residue (or digestat) is stable, deodorized, ridded in
major part of the pathogenic germs and can even be used as
a fertilizer for agricultural purposes. The wastewater treatment
plant sludge valorization by anaerobic digestion process
permits to produce a renewable energy, that was available,
little expensive and no polluting. The biogas production is
considered as an economic solution, decentralized and environmentally
friendly for the sustainable development.