Sand separator / sand screw

The sand separator, also known as a sand screw or solids separator, is used to separate easily sedimenting solids from wastewater or process water.

The dirty water is fed into the container from above. Solids such as sand or slag settle down into the sludge hopper. A screw conveyor ensures that the solids are slowly transported out of the water towards the screw outlet at the top of the device.

The slow rotation of the screw conveyor promotes settling and enables partial dewatering of the solids in the upper section of the conveyor trough. Light materials such as clay flow out with the water via a side outlet on the funnel.

Sand separators are designed with a single or double screw conveyor. To optimise dewatering, a conveyor spiral can be used instead of the screw conveyor.