- Tertiary treatment
- Pre-treatment on membrane filter
- Phosphorous removal
- Algae removal
Sand filtration is a well-known technology for separation of small suspended solids particles in water. The Hydrasand continuous sand filter is an economical sand filter for continuous cleaning of sand to achieve efficient effluent cleaning.
Raw influent is fed into the base of the sand-filled, cone-bottomed filter. The flow then rises through the sand so that clean effluent is discharged over the upper weir. The rising flow of the effluent is distributed evenly over the entire cross-section of the filter by means of a radial grating system.
The contaminated sand falls continuously to the bottom cone outlet, from where it is transferred by an external airlift to the wash chamber at the top of the unit. Final backwashing of the sand is then performed by a counter-current of clean water before the sand returns to the sand bed in the isolation box. The dirty wash water is discharged over the lower weir for disposal.
(Nm3/hr at bars)