Danish Rootzone Techonology for waste water treatment


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Our areas of expertise are in Environmental Engineering, and we specialize in wastewater treatment, sludge mineralization, handling solid waste, air purification (natural ventilation and indoor climate), ecological urbanization projects and education within the above subjects.

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Water purification applying natural technology

Purification and disinfection of surface water, Colombia
Founded in 1572, Villa de Leyva is one of the best-preserved colonial towns in Colombia. Root zone technology is used for the purification of the city’s drinking water. The root zone system serves as a filter that ensures the retention of particles, degradation of organic matter, binding of metals and disinfection. In this type of system, using materials distinctive for their large surface area (granular piers, perlite, etc.) makes it possible to restrain the passage of particles. Using limestone materials has a disinfecting effect that contributes to better water sanitation. (Courtesy: Transform – Danish Rootzone)

Artificial groundwater recharge, Denmark
Contamination of groundwater by chlorinated solvents and pesticides has forced Greater Copenhagen Utility to close many wells and in 1995 a pilot plant for artificial groundwater recharge was established as an alternative to treating surface water with chemicals and chlorine. Surface water is sprayed over an area of 21 hectares and in less than four weeks this surface water is converted to clean groundwater by a sand layer. Although it was subsequently decided not to scale up the pilot plant, the pilot plant nevertheless demonstrated that it is possible to get very good groundwater quality using this method. Geologically speaking, this formation is rare in Denmark, but this method has been used for years in Sweden, Finland and the Netherlands. (Courtesy: Greater Copenhagen Utility and Transform – Danish Rootzone)

Below surface reservoirs, Namibia
In desert and semi-desert areas, surface water resources are often very limited most of the year, and the groundwater is saline or inaccessible. Methods for storing rainfall and increased amounts of surface water from the rainy season for use during the dry periods are therefore in demand. The storage can be done with dams and reservoirs, and here is a special method for groundwater or river dams involving setting up a water barrier in the river bed. A significant amount of water is transported under the surface of the river bed (or wadi or revier) and by placing a dam into the waterbed – beneath the surface – it is therefore possible to dam up the water in the river bed below the surface, thereby reducing both evaporation loss and surface contamination. This solution is used in Namibia, for example. (Courtesy: Transform – Danish Rootzone)

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