The wash water taken from a wheel wash or simular installation can simply be settled in large settlement tanks or in some cases sent to a settlement lagoon. This is perfectly acceptable when the wash water is not spotlessly clean, especially in opencast, waste transfer stations, quarries and construction suites. When wash water really does need to be clean, the only successful method of doing this is with a water recycling system.
The basics are that the vehicle or plant is washed, and the water drains away via a silt trap to an underground interceptor. The water then wears through the underground interceptor in the traditional way. We then take the water from the third stage of the interceptor (the cleanest water) and a suction pump delivers this to our water reclaim unit. Depending on the system the water is either pre filtered through 20 micron filters, or is hydrocycloned to remove any solids. Then an activated carbon filter removes the detergent and the water is then stored in a header tank, ready to be discharged back to the wash unit.
Water authorities in some parts of the country are restricting the use of water or refusing to supply water for vehicle washing. Using a water recycling system actually permits the use of a vehicle wash, when water authorities in certain areas are concerned about the effluent discharge. A full water reclaim system complies with environmental agency requirements. A water reclaim system actually saves money and permits washing during water shortages.