Sewage sludge dryer

Sewage sludge dryer for pressed-out sewage sludges from 20% TS.

The wet sewage sludge is fed via the push floor into a homogenising screw. Via a dry return line, the sewage sludge is mixed to a higher TS content in the homogenising screw in order to dry the sewage sludge in a highly efficient manner and without the normally present bonding problem.

For energy generation purposes, a cyclone combustion chamber with a multi-functional top-mounted burner for the combustion of free-flowing biomass is available. Alternatively, the energy generation can also be realised via a gas burner or the dryer can be integrated into the exhaust gas flow of a BHPP. Thus, the cheapest version can be chosen for the respective location of the plant.

Due to the special sewage sludge drying procedure, the evaporation rates are extremely high and are below a thermal energy of 700 W per litre of water. During the procedure, the hot exhaust gases are transported from the gas and biomass combustion directly into the material dispersal of the dryer. This allows for almost ideal physical conditions for the evaporation of the water.