Proceedings

When sludge is mechanical dewatered, it still is mostly made up of water. Further thermal drying requires a lot of energy to evaporate this water. The cost of sludge treatment is thus mainly determined by the energy cost (e.g. in stand-alone sludge drying, the energy consumption is responsible for more than 50% of the total treatment cost). Reduction of the energy consumption and thus the treatment cost are therefore a prime subject of interest, both to potential operators as to suppliers of such plants.

Waterleau is a Belgian technology developer and contractor in the field of environmental engineering (wastewater treatment, water treatment, sludge and waste treatment and renewable energy).

In this paper Waterleau will give an overview of potential methods to reduce the energy consumption of thermal sludge drying. This will be illustrated with case studies and reference projects. We will show that improvements are the result of combining existing and proven solutions, rather than by inventing something completely new.