Specifications

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6720649497 SM HP270-1 2012/09 en
> 300 0 0 / +
Free chlorine (Cl
2
)
< 1 + +
1 – 5 + 0
> 5 0 / + 0 / -
Hydrogen Sulfide (H
2
S)
< 0.05 + +
> 0.05 + 0 / -
Free (aggressive) carbon
dioxide (CO
2
)
< 5 + +
5 – 20 + 0
> 20 + -
Total Hardness (ºdH) 4.0 – 8.5 + +
Nitrate (NO
3
)
< 100 + +
> 100 + 0
Iron (Fe)
< 0.2 + +
> 0.2 + 0
Aluminium (Al)
< 0.2 + +
> 0.2 + 0
Manganese (Mn)
< 0.1 + +
> 0.1 + 0
Symbols explanation:
+ Good resistance under normal conditions
0 Corrosion problems possible, particularly when there are other factors rated 0
- Use is not recommended
Table 5 – Water composition parameters
Table 5, gives an idea of the resistance of AISI 316 stainless steel and pure copper (99,9%) in water to corrosion
by some important chemical factors. However corrosion is a very complex process influenced by many different
factors in combination, this table is a considerable simplification, which should be taken in consideration.
6.3 Types of scale
Calcium carbonate (CaCO3) can be formed when calcium or bicarbonate alkalinity is present. An increase in heat
and / or an increase in pH will cause precipitation of calcium carbonate
.
Calcium Sulfate (CaSO4) is 50 times more soluble than calcium carbonate and will, therefore, precipitate only after
calcium carbonate is formed. This type of scale can exist in various forms, and its formation depends strongly on
the temperature. An increase in temperature decreases the solubility of this salt and increases the risk of scaling.
Water scaling tendency
In order to estimate the scaling tendency of natural water, several parameters must be analysed and determined: