Sand washer

One of the serious problems in wastewater treatment plants is the contamination of separated sand with an organic suspension. This affects both the limitation of sand storage in landfills and the deficiency of organic matter in the further process of wastewater treatment. An effective solution to this problem is the use of a sand scrubber as a complementary element to the sand trap or sand separator.

The task of the device is to rinse the organic suspension from the sand coming from the sand trap or separator, and then dehydrate the sand before discharging it into a waste container. The sand pulp is fed to the conical part of the scrubber and swirled by a mixer. In addition, compressed air is supplied from the bottom to intensify the contact of sand with the rinsing water. The granular suspension (mainly sand) is directed outwards by the centrifugal force and slides down the walls of the tank. The lighter organic suspension flows naturally upwards. Water is supplied and emptied to the device cyclically. After the specified time of rinsing, the sand sedimentation takes place and the dirty water is replaced with clean water. After reaching the preset level of sand in the funnel, the screw conveyor is activated to remove the sand outside the device, while the suspended organic suspension is periodically removed by opening the valve on the sewage discharge conduit to the sewage system. The device operates in an automatic cycle controlled by a programmable controller with a touch screen. A set of sensors installed in the device controls the process of sand separation and removal of organic pollutants.