Thermal treatment of wastewater biosolids: evaluation of an italian case

The right individuation of the more convenient solution for final treatment and destination of sewage sludge is a very interesting problem, in account of the urgent need for acceptable solutions. In this work we examined, both from the technological and from the environmental point of view, the thermal solutions (direct combustion in incineration plant first of all, but also gasification), for the sludge deriving from the main Italian wastewater plant (plant of the metropolitan area of Torino). In order to arrive to propose a solution a first analysis was necessary in order to define the main characteristics of the produced sludge (flow rates, composition); afterwards we analyzed in detail the potential plant design solutions by arriving at the end to some perspective indications.