Process for thermal upgrading of clarified sludge

摘要

De-watered sludge is mixed and ground with coal and then thermally dried, before firing as fuel in a power station. Pref. the moisture of the mixture is reduced below 10%, by introducing hot air, or an air-flue gas mixture, into the mill where the mixing and grinding takes place. The hot air is introduced at between 250 and 450 degrees C. The resulting product is immediately fired into the furnace with steam and air, and if necessary, flue gas containing exhaust vapours.