Sizing of Wastewater Sludge Anaerobic Digesters

Wastewater sludge treatment and disposal have always created more problems than wastewater treatment itself. This is rooted in the fact that in contrast to wastewater, which continuously passes through the wastewater treatment plants (WWTPs) without affecting (in quantitative sense) the natural hydrological cycle, sludge is entirely accumulated there. Due to its specific properties, the accumulated sludge inclusion in the natural cycles of mass transfer “in an economically and environmentally acceptable manner” [14] is more difficult. This is because sludge management is associated with overcoming serious technological and economical problems, some of which have not received satisfactory solution as yet. Biological stabilisation of municipal wastewater sludge is one of them, irrespectively of the availability of significant experience and the long historical development of this issue.