Price on application.

General Description

Please contact us for a price. Colour in water (after it has been mechanically filtered) is typically caused by organic compounds. If the colour is due to iron or manganese there are specific treatments (see the iron and manganese section). If the colour is due to organics then treatment is normally by ion exchange or activated carbon. Organic colour comes from decaying vegetation and may be completely soluble or particulate. Tannins (Humic and Fumic acids) are by far the most common class of compounds and give the water a yellow/brown tint. In highland areas where water runs off peat the water can be heavily coloured. When the water passes through anion resin beads the organic molecules are bound to the resin. When the resin has become saturated and can hold no more colour forming compounds they need to be removed. Resin selection is critical as many require caustic soda to remove the organics. However there are resins available which can be regenerated with brine on its own or in combination with caustic. Brine has the advantage of being readily available and safe. Typically every 25 litres of resin will take out 2000 ppm of organic colour before it needs regenerating.