DE-ironing
Water/ Fertilizer systemsPrinciple of de-ironing
Water in underground springs and boreholes can dissolve Iron and Manganese from the surrounding rocks. The water under ground is devoid of Oxygen, and the Iron and Manganese are soluble in water because of this.
However, when the water is pumped to the surface and exposed to the Oxygen in the air, the Iron and Manganese become insoluble. This cause them to precipitate out of the water, leaving deposits in your tanks, pipes and taps.
Iron and Manganese can affect equipment and systems and are therefore often minimized by treating the water. For the iron removal and demanganization of water, the (spring) water is brought into intensive contact with oxygen. In various sub-processes, via oxidation, hydrolysis, nucleation and precipitation, the Iron and Manganese are ultimately filtered out. In this process the 2-valued, soluble forms of Iron and Manganese present in the water are converted into very poorly soluble forms.
As a result of this physicochemical process (also known as electrokinetic adsorption), it becomes possible to filter the Iron and Manganese particles. For this, use is made of annealed and sieved river sand, which is selected on the basis of the supply water and the desired end result. The first precipitation of Iron Hydroxide has a positive effect on the further precipitation of both Iron and Manganese.
Due to this catalytic effect, clean filter sand must run in for some time before the Iron removal starts properly. The same principle applies to the demining process. The final quality of the de-ironed water depends on various parameters such as the pH value (acidity) of the water, the oxygen concentration, the buffering capacity of the source water, the flow rate, and the selection of the filter medium.