3.696.5275.210
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The blowdown from the Compact steam generator can flash to steam when
introduced to atmospheric pressure.
Spirax Sarco recommends the use of automatic blowdown valves with it’s generators.
The buildup of scale and dirt within the unit can effect operation and the quality of the
clean steam and shorten the life of the unit. The unit should be blown down
a minimum
of once a day.
The frequency of necessary blowdown is directly effected by the minerals, chemicals, and
contaminants contained in the feed water.
Depending on the water, the blowdown interval may need to be altered (either more
or less frequently) for each site.
Water Quality
Feedwater Pipework. The feedwater in the feedtank must be recirculated. The feedwater
will be recirculated to minimise stagnant water within the system, and to assist in the
removal of non-condensable gases. Water within the feedtank should be maintained above
80°C. HTM 2031 gives specifications for contaminants within the steam condensate, as
identified in the table below:
Determinand
Unit
Maximum Permitted Values
HTM 2031 Clean Steam Condensate
Acidity or Alkalinity
-
NQ
Degree of Acidity
pH
6 - 8
Ammonium, NH
1
mg/lt
≤
0.2
Calcium and Magnesium
mg/lt
NQ
Total Hadness, CaCo
3
mg/lt
< 2
Heavy Metals
mg/lt
≤
0.1
Iron, Fe
mg/lt
< 0.1
Cadmium, Cd
mg/lt
< 0.005
Lead, Pb
mg/lt
< 0.05
Heavy Metals
mg/lt
≤
0.1
Chloride, Cl
mg/lt
0.5
Nitrate, NO
3
mg/lt
0.2
Sulphate, SO
4
mg/lt
NQ
Oxidisable Substances
-
NQ
Residue on Evaporation
mg/lt
30
Silicate, SiO
2
mg/lt
< 0.1
Phosphate P
2
O
5
mg/lt
< 0.1
Conductivity at 20°C
µS/cm
35
Bacterial Endotoxins
EU/ml
0.25
Appearance
Clear, colourless
Содержание CSM-C
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