Water as a Challenge
Hard water, wherever it comes from, well or water pipe, may turn out to be very expensive – without counteraction calcification cannot be avoided.
The harder the water the more scale can be found at the hottest spots in the water system – boiler, flow heater, washing machine, etc. – high energy costs and intense mending are the consequences.
How can formation of boiler and mineral scale be safely prevented?
By eliminating the lime producers (calcium and magnesium salts) from water – and this is done by softening or demineralisation units.
One thing is clear: If there are no more lime salts in the water, no more limescale is generated.
Only softening or demineralisation units eliminate lime salts from water and hence are always effective.
These units replace calcium salts with sodium salts by means of an ion exchange resin (water softening) or just fix all ions to a resin (demineralisation).
Sodium salts are not able to form a scale deposit due to their very high water solubility, even at high temperatures.
As soon as the ionexchange resin is saturated with calcium salts (= lime or scale) the resin is regenerated with a concentrated saline solution; this saline solution is pumped through the unit and is subsequent released to the sewer. Regeneration is done fully automated!
As soon as the demineralisation resin is exhausted is has to be replaced; the saturated resin is returned and recycled by specialised companies.
For a use as drinking water soft water has to be blended (mixed) with raw water until a hardness of 8°dH is reached, because this is stipulated by the Austrian Drinking Water Regulation (TrinkwasserVO 2001).
Corrosivity as a Companion of Water Treatment
But naturally soft or softened/demineralised water is – the other side of the coin – always corrosive. Hence it is absolutely necessary to adjoin an appropriate corrosion protection agent to the water, at best straight behind the softening/demineralisation unit, by means of a quantity based dosing pump. Thereby it might be absolutely enough to keep the pH value with the correct range.
Even with a total demineralisation corrosivity of water is preserved; at a low pH value OH–– und H+-ions of the water continue the corrosive attack. Even then the treatment with an approved corrosion protection agent is advisable. But for drinking water a demineralistaion is not intended, according to above mentioned Drinking Water Regulation.
Only an elimination of lime producers (calcium salts) prohibts safely formation of limescale. Consequently the installation of a softening or demineralisation unit is always successful. And based on the condition of the treated water one should always pay attention to appropriate measures for corrosion prevention.
To cover water treatment thoroughly you should deal closer with the following topics:
- Demineralisation incl. RO plants
- Decalcification and/or Scale Removal for clearance of consequences including the appropriate
- Decalcification Technique as well as
- Corrosion Protection for a sustainable damage mitigation.
Dr. Ing. Franz Böhm GmbH – Ihr Experte für Anlagen zur Wasseraufbereitung