OBJECTIVE: To establish a procedure for action to be taken where critical parameters exceed acceptable limits within the purified water system.
SCOPE: This Standard Operating Procedure applies to the generation and distribution of purified water systems.
RESPONSIBILITY: Officer, Executive – Engineering Department.
Head – Engineering Department for overall compliance to this SOP.
ACCOUNTABILITY:
Head of Engineering
PROCEDURE:
Soft Water Hardness: If soft water hardness exceeds 5.0 PPM:
- Stop the Reverse Osmosis system and close the Reverse Osmosis inlet valve.
- Next, Drain the water from the soft water storage tank.
- Verify the functioning of the softener unit for regeneration.
- Manually regenerate the softener unit and recheck hardness.
- If hardness is within limits, collect water in the soft water tank and restart the RO system.
pH Adjustment:
- If pH before RO is below 7.5:
- Increase Sodium Hydroxide (NaOH) solution dosing.
- If pH before RO is above 8.0:
- Decrease Sodium Hydroxide (NaOH) solution dosing.
Pressure Drop across MCF-1 micron:
- If the pressure drops across MCF exceeds 0.8 kg/cm²:
- Replace the MCF.
Related SOP: SOP on a collection of Swab and Rinse Water samples
ORP Value: If ORP value exceeds 350 mV:
- Check free chlorine at the softener outlet.
- If >2 ppm, reduce chlorine dosing to 2 ppm and follow steps 4-7.
- If 2 ppm, adjust SMBS dosing for chlorine removal.
- Stop the soft water pump.
- Drain water from a soft water tank.
- Collect fresh soft water in the tank.
- Start soft water pump & SMBS dosing.
RO Conductivity:
- If RO conductivity exceeds 30 µS/cm:
- Check RO feed water hardness.
- Check RO feed water pressure (5.0-9.0 kg/cm²).
- Inspect RO membrane port ‘0’ rings.
Related SOP: SOP for Operation & Calibration of Water bath
RO Feed Pressure (5.0-9.0 kg/cm²):
- If RO feed pressure is beyond limits:
- Check for rupture; replace RO membranes if found.
- Check for fouling; perform chemical cleaning if fouling is detected.
EDI Conductivity:
- If EDI conductivity exceeds 1.0 µS/cm:
- Check EDI feed water conductivity.
Distribution Conductivity:
- If distribution conductivity exceeds 1.0 µS/cm:
- Drain storage tank and user points.
- Collect fresh water in the storage tank.
- Recheck storage tank water conductivity.
- If still high, perform hot water sanitization.
UV Tube Intensity (2.4 MW/cm²):
- If UV tube intensity is less than 2.4 MW/cm²:
- Replace UV tubes.
ABBREVIATION:
SOP: Standard Operating Procedure
RO: Reverse Osmosis
Related SOP: SOP on Microbiological Monitoring of Compressed Air
REVISION HISTORY:
Nil
