A safe disposal of sewage sludge from the waste water treatment is an urgent problem which, in respect to increasing environmental conditions, is associated with further increasing costs. The sewage sludge drying procedure becomes increasingly important and requires technically efficient and economical systems. With our dryer series SpeedRotation STR, we provide a dryer system that revolutionises the sewage sludge drying procedure. With only 650 W of thermal energy for the evaporation of 1 litre of water, we have reached the threshold of what is physically feasible.
This is possible since our Speed Rotation dryer provides the ideal physical conditions required for a highest possible efficiency. Wet sewage sludge is mixed via a dry return mixing line to a value below the bonding limit and is then fed into the drying chamber. Quickly rotating blades constantly keep the sewage sludge in a material cloud within the drying chamber. By means of this procedure, the maximum surface for the product is created. The moisture and the simultaneously incoming hot air (350°C) are in direct contact for the change of state. The high thermal kinetics results in a turbo drying procedure. Within a few minutes, the sewage sludge is dried from a moisture of 80% to a residual moisture content of 10%. The material flow controls itself fully automated and adjusts itself to variations in the raw material or energy supply.
The dryer can be supplied from different energy sources or even combined in order to ensure the cheapest energy supply on-site. The dryer can be integrated into the exhaust gas flow of a sludge gas BHPP. It can be directly supplied via a gas burner or via our top-mounted burner for all free-flowing biomass fuels. Therefore, our multi-functional top-mounted burner can be also operated with dried sewage sludge. It can be ensured that energy is provided at lowest costs.