Danfoss iSave 50, Руководство по эксплуатации

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Design guide Start and stop of the SWRO with iSave unit
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180R9357 | AQ265943679828en-00100
2
IOM iSave 50 - 70 | 0
3
.202
3
4. Start the iSave(s).
In general: Only start the iSaves when the
pressure ”HP in” (10) is below 20 barg/290
psig. Always start the iSave unit before the
high-pressure pump is started.
There are in principle two ways to start multi
ple iSaves:
- Slowly ramp up all the iSaves at the same
time.
- Slowly ramp up one by one.
Starting sequence - one by one:
a) Start iSave #1.
b) After 5 sec. start iSave #2.
c) In a sequence of 5 sec. start the
remaining iSaves.
Comments:
- Ramp up time on iSaves is set between
10 –15 sec.
Starting sequence - Start all iSaves at the
same time.
Comments:
- Ramp up time on iSaves is set between
10 –15 sec.
If the pressure (10) at ”HP in” drops below
3 barg/43.5 psig, the sound will change of
the iSave. This is due to cavitation. ”HP in”
pressure at 3 barg/43.5 psig is acceptable
for less than 10 min. within a period of 6
hours. Run the iSave at its min
allowable speed during this period to
reduce cavitation.
5. With a pressure control valve (15), adjust the
back pressure of the “LP-out” to fulfill the
minimum presure requested in the Data
sheet. (May only be necessary at initial start
up).
6. An “over flush” of the iSave can be done to
bleed any remaining air from the system.
Flush over a period of minimum 2 minutes.
7. Adjust the speed of the iSave unit to desired
flow (rpm). The speed is controlled by a VFD.
8. Start the high-pressure pump(s) (4), and the
system pressure (5) will rise until the
permeate flow (17) almost equals the flow (2)
from the high-pressure pump.
9. For iSave 21 and iSave 40:
Check the low pressure flow rates (12), and if
required, adjust flow with valve (15) to
achieve balanced flow to the iSave(s).
1. If the “LP-in” flow (12) is too low and the
“LP-out” pressure (14) is higher
than 1 barg/14.5 psig, increase flow and
decrease pressure by opening the
pressure control valve (15).
2. If the “LP-in” flow (12) is too low and the
“LP-out” pressure (14) is below 1 barg/
14.5 psig, adjust the flow by raising the
flow from the seawater supply pump (A).
3. If the “LP-in” flow (12) is too high, reduce
flow by closing the pressure control
valve (15) or the flow from the seawater
supply pump (A).
10. For iSave 50 and iSave 70:
Check the low pressure flow rates (12), and if
required, adjust flow with valve (15) to
achieve balanced flow to the iSave(s).
1. If the “LP-in” flow (12) is too low and the
“LP-in” pressure (21) is higher
than 2 barg/29 psig, increase flow and
decrease pressure by opening the
pressure control valve (15).
2. If the “LP-in” flow (12) is too low and the
“LP-in” pressure (21) is below 2 barg/
29 psig, adjust the flow by raising the
flow from the seawater supply pump
(A).
3. If the “LP-in” flow (12) is too high, reduce
flow by closing the pressure control
valve (15) or the flow from the seawater
supply pump (A).
Daily system shutdown
1. The system is running in normal operation
and producing permeate flow.
2. Stop the high-pressure pump (4).
3. Keep the iSave(s) (11) running until the
TDS in the high-pressure line is equal to the
TDS in the low-pressure line.
NB! If the pressure (10) at “HP in” drops
below 3 barg/43.5 psig, the sound will
change of the iSave. This is due to
cavitation. “HP in” pressure at
3 barg/43.5 psig is acceptable for less
than 10 minutes within a period of 6
hours. Run the iSave at its min
allowable speed during this period to
reduce cavitation.
4. Stop the iSave(s)(11).
5. Stop the seawater supply pump (A).