Lime saturation
If calcite does not tend to dissolve or separate calcium carbonate when it comes into contact with water , then one speaks of calcite or calcium carbonate saturation . If there is a lowering of the pH value of the water due to an excess of carbonic acid , it has a calcite-dissolving effect. However, if the pH rises, this leads to supersaturation (it then has a calcite-separating effect). In all cases a dynamic chemical equilibrium is established .
Drinking water should not be the provisions of the Drinking Water Regulations calcitlösend accordance, otherwise materials that are calcareous (z. B. concrete ), can be attacked and the protective layer formation is prevented on metallic surfaces. There is therefore a need to remove excess carbonic acid from calcite-dissolving drinking water by deacidification .