Iron and manganese often cause the main problem of the waterworks' due to the substances' discolouring of the washing and sanitation at the consumer. Typical signs of increased iron and manganese content in the water are ochreous or dark water with a metallic taste.
Raw water can contain different types of iron dependent on where in the country you are. Sand filtration is thus not always sufficient. It may therefore be necessary to use other methods in order to ensure continous iron-free water. These differences cannot be seen in the ordinary analyses but calls for know-how and experience to determine iron type and treatment method.
After the oxydation, iron and manganese can be filtered through sand filtration. The filter materials used for removing iron are Gravel lll and Nevtraco l. For removing manganese, Hydrolit-Mn is used. Also, the filter media Demantex has proven to be a very efficient material for manganese removal, even under difficult conditions with low pH values where many other types of filter media are insufficient.
Reduction of iron, manganese, ammonium, and aggressive carbon dioxide in Danish waterworks. The water treatment plant consists a.o. of 4 TFB 35 pressure filter plants.