Columbia CT Series, Инструкция по установке, эксплуатации и обслуживанию

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FM-148 COLUMBIA BOILER COMPANY, REV 6-06
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WATER TREATMENT
Proper treatment of make-up water and boiler water is necessary to prevent scale, or other
deposits, and corrosion within the boiler. The absence of adequate external and internal
treatments can lead to operational upsets or total boiler failure. Where a choice is avail-
able, pretreatment external to the boiler is always preferred and more reliable than treat-
ment within the boiler.
Instructions for feed water treatment as prepared by a competent feedwater chemist should
be followed. Do not experiment with homemade treatment methods or compounds.
Representative samples of feed water and boiler water must be analyzed frequently to
ensure that they are in specification.
the following terms and guidelines are to be used in
conjunction with the advice of a water treatment specialist.
Recommended Guidelines for Boiler Water Treatment
RECOMMENDED
ANALYSIS COMMENTS
RANGE
pH 10-11 Low pH promotes corrosion
Total Alkalinity 200-700 ppm Low: promotes corrosion
Phosphates 30-100 ppm Prevent scale formation
Total Hardness 0-50 ppm Prevents scale formation
Chlorides 60-200 ppm A measure of proper blow down
Total Dissolved Solids 2000 ppm Maximum High solids may cause surging
Sulfites 20-30 ppm A good oxygen scavenger
Specific Conductance < 700 micro ohms cm A measure of proper blowdown
Oxygen < .007 mg/liter Prevents corrosion and pitting
ppm = parts per million
Use proper water treatment to prevent the buildup of scale on the boiler. After scale has
built up on the walls of the boiler it is almost impossible to remove it from the boiler. The
introduction of acids into the pressure vessel is thoroughly discouraged, since virtually any
solution that will chemically attach the scale will also attack the boiler metal.
pH
The pH value of the boiler water is a number between zero and fourteen. Values below
seven are acidic, seven is neutral, and values above seven ar alkaline.
The pH factor is the most important factor influencing scale formation and the corrosive ten-
dencies of boiler water. The pH should be maintained between a minimum of 10.5, and
a maximum of 11.0 to prevent acidic corrosion of boiler tubes and plates, and to provide