How to start and stop the Fresh Water Generator [FWG]

Starting of Fresh Water Generator:

1. First we need to start the ejector pump.

• Full open ejector pump valve and sea water discharge valve.
• Start the pump.
• Slowly open ejector pump outlet valve its because not to act rapid pressure to the condenser and water ejector.
• Check the inlet pressure on water ejector is greater then or equal to 4 bar.
• Check that condenser air outlet valve is functioning correctly.

2. Intake of feed water:

• Open the feed water adjust valve.
• Adjust the feed water pressure so that it falls in a range of 0.4 - 0.6 bar.
• If the feed water pressure fails to increase, slowly close cooling water outlet valve to adjust the feed water  pressure.

3. Start the chemical injection unit.

4. Check the degree of vacuum in evaporator to 0.9 bar.

5. Injecting the hot water.

• Slowly open the hot water inlet valve to fully opened position.
• Through the air outlet valve situated at the top of the shell of heater , fully release the air from heater shell.
• slowly open the hot water outlet valve to the fully open position.
• Adequately close the hot water bypass valve to adjust hot water flow rate.

6. Switch ON the power of salinity indicator.

7. Check the generated distillate.

• Check that the distillate is visible through the sight glass on the distillate pump suction side.

8. Starting the distillate pump.

• Start distillate pump.
• Open the distillate pump outlet valve.
• Adjust, outlet pressure to a range of 1.4 to 2.2 bar.
• Prevent the sight glass from being filled with water otherwise the heat transmission area of the condenser decreased.

9. Checking the amount of distillate:

• Means the amount of generated distillate using flow meter after running FWG for 30 minutes.

Stopping of Fresh Water Generator :

• Open fully the hot water by pass valve.( by closing gradually).
• Close fully the hot water outlet valve. (by closing slowly).
• Close the hot water inlet valve.
• Stop the fresh water distillate pump by closing outlet valve.
• Cool down the heater by running ejector pump for 30 minutes to supply the feed water to the heater.
• Stop the chemical injection unit.
• Salinometer should be switch off.
• Stop the ejector pump and open air vent.
• Close the suction and discharge of valves of the ejector pump.
• Close the overboard vlave for combined brine or air ejector.
• Valve of the fresh water tank to be closed.

*Remember the air to be ramained open