The watepower plant is based on wet anaerobic digestion of input materials, where organic substances are degraded by microorgaisms in the absence of oxygen (anairobic condition) at a temperature of approx 35°-37° (mesophil process) or at 50°-55° (thermophilic process).
The input biomass (deriving from farming and agriculture) is pumped into a pre-treatment area to make a particular organic liquid mixture.
The mixture then passes to a highconcentration, wt digestion process.
The main sub-products of anaerobic digestion are biogas and digestate. Biogas is a gaseous mixture mainly composed of methane and carbon dioxide, and is suitable for the combined production of eletrical and thermal energy. Digestate is the output sludge resulting from anaerobic digestion, and is separated into two fractions: a solid one and a liquid one.
The liquid fration can be strored in specifically designed tanks or sent to treatment or disposal. The solid fraction can be piled on concrete flooring, They can also be spread over land during the appropriate period. For the most part, liquid fraction is re-sent to the pre-treatment area; remaning is re-used in the composting section or sent to the depuration treatment.