SALTEC Screw Press (SP) is based on a shaft screw conveyor that transports the material to the press zone for higher dewatering. The material is dewatered in the long conveyor of the Screw Press. At the end, a plug is formed of the already dewatered sludge, and through the pressure that can easily be adjustable. The DS-content is increased on the outlet sludge. The shaft based screw makes it specially suited for materials that tends to clog together. Shafted screw spirals reduces the need for maintenance, as they can work with a significantly higher rate of filling in the conveyor.