AgroEnergien products

SMD is a patented digester (up to 2.400m³ volume) with two upright cylindrical tanks, one inside the other, without mixers. The only moving part is a gas valve situated in a wide gas pipe connecting the two chambers. The efficient agitation process in the SMD is achieved by mixing intervals based on the formation of biogas and a pressure-controlled function of the gas valve. Conventional biogas plants work with different types of agitators in the fermenting chambers; they require additional electricity and must be maintained regularly.

The AgroEnergien Mississippi Digestate Dryer is suitable for efficient, bonusworthy heat utilisation, for drying digestate to reach a dry matter content of max. 12%DM. The structure of the digestate dryer is similar to the paddle wheel of the legendary Mississippi-steamboat. With every rotation, the paddles on the back side of the dryer immerge into the digestate that is to be dried. While going through the digestate, it is homogenised, so that the buildup of floating layers, incrustations and sedimentary depositions is impossible. On the front side of the digestate dryer, the paddles emerge from the digestate and carry a certain amount of the substrate, which is then dried in the airstream. A heat exchanger, which is adjusted to the available amount of heat, is connected upstream of the digestate dryer. Cold external air is heated by flowing through ventilators connected upstream of the heat exchanger. After flowing through the AgroEnergien Mississippi Digestate Dryer, the damp and ammoniacal air is then cleaned in air purification system and finally escapes into the air.

The starting point: The agricultural use of sludge is not ensured in the long run: Apart from heavy metals, sludges can contain organic pollutants (residues of pharmaceuticals, fragrances, plasticisers, etc.) as well as pathogens, of which the effects due to bioaccumulation and combination effects are barely assessable. In conventional procedures, a thermal removal of the sludge is often accompanied with high costs and pollution, due to the transport of sludge with a high water content (filter cake has a water content of approx. 70-80%) and the use of fossil fuels while drying, among other things. On the other hand, sludge drying concepts based on the use of low-temperature heat and solar energy are gaining in importance.