Danfoss iSave 21, Руководство пользователя

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Instruction Start and stop of the SWRO with iSave unit
3 180R9213 / 521B1164 / DKCFN.PI.003.F2.02 / 03.2011
Starting up the system
1-3 days system shutdown
1. Make sure that all valves are set in normal operating positions.
2. Start the seawater supply pump (1)
3. Make sure all pipework is flushed with water.
Vent all air from the system through air valve (8) and iSave unit (11).
iSave has ¼” plugs to vent both the HP and LP side.
4. Start the iSave unit when the pipwork is full of water and the system and iSave unit has been bled.
NB! Always start the iSave unit before the high-pressure pump is started.
The speed of the iSave unit must be ramped up over a period of minimum 10 seconds.
If possible run the iSave at maximum 750 rpm.
5. With a pressure control valve (15), adjust the back pressure of the “LP-out” to a minimum
of 1 bar/14.5 psig (14).
6. An “over flush” of the iSave can be done to bleed any remaining air from the system.
Flush minimum 10% higher flow rate (12) at “LP in” compared to the flow rate on “HP out”.
Flush over a period of minimum 5 minutes.
7. Adjust the speed of the iSave unit to desired flow. The speed is controlled by a VFD.
8. Start the high-pressure pump (4), and the system pressure (5) will rise until the permeate flow (17)
almost equals the flow (2) from the high-pressure pump.
Check the low-pressure flow rates (12), and if required, adjust flow to achieve balanced flow to the
iSave unit. It might be a benefit to “over flush” the iSave with up to 10% to lower the mixing.
1. If the “LP-in” flow (12) is too low and the “LP-out” pressure (14) is higher
than 1 bar/14.5 psig, increase flow and pressure on the pressure control valve (15).
2. If the “LP-in” flow (12) is too low and the “LP-out” pressure (14) is below 1 bar/
14.5 psig, adjust the flow by raising the flow from the seawater supply pump (1).
3. If the “LP-in” flow (12) is too high, reduce flow by the pressure control
valve (15) or the flow from the seawater supply pump (1).
9. Check that the pressure (14) of “LP-OUT” is at least 1 bar/14.5 psig.
1. The system is running in normal operation and producing permeate flow.
2. Stop the high-pressure pump (4).
3. Keep the iSave unit (11) running until the wanted pressure (5) at the membranes is reached and 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 bars/43.5 psig, the sound will change of the
iSave. This is due to cavitation. “HP in” pressure between 1-3 bars/43.5 psig is acceptable for
less than 10 minutes within a period of 6 hours. Also see datasheet for iSave.
If possible run the iSave at maximum 750 rpm.
4. Stop the iSave unit (11).
5. Stop the seawater supply pump (1).