Performance of the Wendewolf® The Wendewolf® moves and aerates up to 250 m³/h of sludge! The automatic programme ensures a continuous flow of the freshly pressed sludge through the drying bed. The required energy consists of electricity only, between 10 kWh to 30 kWh per ton of water evaporated. Industrial dryers require between 800 and 1000 kWh in thermal energy and electricity. Therefore the running cost of Wendewolf® is extremely low! However the system requires space to be built. As Wendewolf® is successfully used in the European climate, with an annual evaporation of 800 - 900 kg/m²year, we anticipate for example the double in the Middle East. The End Product When drying the sludge with the Wendewolf® , the volume decreases linearly to the water loss, thus leaving only 1/5th of the original mass to be evacuated. The original sludge is transformed into a granular bio-solid which is easy to handle and which can be stored in heaps, containers or bags. The granulate is odourless and if an agricultural use is permitted it can be spread with conventional machinery. Saving Cost through Solar Drying In Europe the reason for drying the sludge is the high cost of the final treatment, so each ton of water extracted from the sludge lowers the annual cost for the water plants. Solar drying requires space and initial funding, but the running costs are extremely low. Wendewolf® yields an end product which has the same high quality as industrially dried material but at a lower running cost.