Lime is not only present as rock in nature, but also in dissolved form, as calcium carbonate (CaCO3) and magnesium (Mg) in water. If the mineral content is high, we speak of hard water.
How does lime get into the water?
The percolating, acidic rainwater dissolves minerals from the soil on its way from the surface to the groundwater and transports them in dissolved form past the waterworks and into our households.
Lime is basically very poorly soluble in water. It is converted into a readily water-soluble form by reaction with carbonic acid, which is bound by means of precipitation from the air. The amount of dissolved lime is related to the carbonic acid content in the water. This balance is called the lime-carbonic acid ratio.
A change in this lime-carbonic acid equilibrium causes the lime to convert back to its non-water-soluble form.
Stress potential in pipelines exerts an attractive force on the minerals (lime) in the water, so that they bind and settle there. A lime layer (lime deposit) is formed, which is harmful to all water-bearing pipes and equipment and entails considerable costs.
Lime is not just lime
Lime directly from natural water sources contains an above-average volume of carbonic acid and is successively exposed to flow dynamics and air molecules, which stabilize the carbonic acid-lime balance.
Lime after water treatment is located in closed piping systems and is exposed to constant mechanical pressure. This disturbs the carbonic acid-lime balance, which is why calcification progresses aggressively.
