Data for rapid calculations of Practical Scaling Index for adiabatic pre-cooler
Conductivity
(µS/cm)
A
Temperature
ºC
B
Calcium hardness
(PPM as CaCO
3
)
C
Total alkalinity
(PPM as CaCO
3
)
D
Alkalinity
(PPM as CaCO
3
)
pHeq
50-300
301-1000
1001-3000
3001-5000
0.1
0.2
0.25
0.27
10-13
14-17
18-21
22-27
2.3
2.2
2.1
2.0
10-15
16-25
26-40
41-70
71-100
101-140
141-200
201-250
251-300
301-350
351-400
401-450
451-500
0.70
0.90
1.10
1.35
1.55
1.70
1.85
1.95
2.05
2.12
2.18
2.24
2.28
10-15
16-25
26-40
41-70
71-100
101-140
141-200
201-250
251-300
301-350
351-400
401-450
451-500
1.10
1.30
1.50
1.75
1.90
2.10
2.25
2.35
2.45
2.52
2.58
2.63
2.68
50
100
200
300
400
500
7.0
7.5
7.9
8.2
8.4
8.5
Calculation of Practical Scaling Index
Instructions:
1. Obtain values of A, B, C and D from above tables
2. pHs = ( 9.3 + A + B ) – ( C + D )
3. Practical Scaling Index = 2 pHs – pHeq
-
if Index is 6.0, water is stable
-
if Index is above 6.0, water is scale dissolving
-
if index is below 6.0, water is scale forming
With Practical Scaling Index below 5.5, minimum recommended water flow in table "Minimum water flow rates"
needs to be increased, contact your local BAC-Balticare representative for support.
Biological control
The adiabatic pre-cooler and its controls have been designed to minimize the risk of uncontrolled growth of algae,
slimes and other micro-organisms such as Legionella:
1. Direct water system, no water recirculation
2. Complete drying of the pre-cooling system after each adiabatic cycle
3. Complete draining of all water distribution piping installed on the unit after each adiabatic cycle
CAUTION
The owner of the equipment is responsible for draining of all water piping feeding the adiabatic
pre-cooler to avoid stagnant water conditions.
4. Use of potable water supply at temperatures of 20 ºC or less, where Legionella is dormant
5. Aerosol free operation
When basic housekeeping practices are followed, and when the guidelines for operation and maintenance of this
bulletin are followed, problems related to uncontrolled growth of micro-organisms will be avoided.
W W W . B A L T I M O R E A I R C O I L . E U
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