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Phosphate (P
2
O
5
)
≤0.1 mg/kg
Conductivity
≤3 μs/cm
pH value (degree of acidity)
5 to 7
Appearance
Colorless clean without
sediment
Hardness (Σ Ions of alkaline earth)
≤0.02 mmol/l
Compliance with the above data should be tested in accordance
with acknowledged analytical methods, by an authorized
laboratory.
3.6.2
Drain Cooling
The feed water supplied to the drain cooling must meet the following
requirements:
Hardness: 0.7 - 0.2 mmol/l.
Water temperature shall not exceed 15°C (59°F).
3.6.3
Reverse Osmosis
A Reverse Osmosis (RO) system may be used to improve the quality
of the water used to generate steam in the autoclave chamber.
In RO, the water is forced through a semi-penetrable membrane, which
filters out contaminants to a high degree of efficiency. In deionisation
(DI) ions and charged particles are removed either by electric fields or
by ion exchange in resin beds.
Although the RO cannot normally attain the degree of purity possible
with the DI methods, it is more than adequate for the feed water
intended for clean-steam generators.
Moreover the RO has several advantages:
1.
RO is cheaper to install and to run than DI.
2.
RO removes particulate matter, organic molecules and pyrogens that
DI cannot remove
3.
RO water is less corrosive to steel and copper than DI water.
4.
RO maintenance requirements are less demanding than those of the
DI units.
Therefore the use of mineral free water will contribute to better
performance and longer life of the autoclave.
