Pre-Start-Up Check and Commissioning Audit
After having loaded the elements into the pressure vessels and before starting up the membrane unit, make sure that the whole pre-treatment secti analysis of the water entering the membrane unit must be made. Furthermore, absence of chlorine, turbidity and SDI must be determined.
The raw water intake must be stable with respect to:
• Flow
• Turbidity
• Temperature
• pH
• Conductivity
• Water Analysis report
The following checks of the pre-treatment system and the membrane unit are recommended for the initial start-up (results to be included in the start-up report):
Pre-Start-Up Checklist
- Corrosion resistant materials of construction are used for all equipment from the supply source to the membrane including piping, vessels, instruments and wetted parts of pumps
- All piping and equipment is compatible with designed pressure
- All piping and equipment is protected against corrosion
- Media filters are backwashed and rinsed
- New/clean cartridge filter is installed directly upstream of the high pressure pump
- Feed line, including RO feed manifold, is purged and flushed, before pressure vessels are connected
- Chemical addition points are properly located
- Provisions exist for proper mixing of chemicals in the feed stream
- Dosage chemical tanks are filled with the right chemicals
- Provisions exist for preventing the RO system from operating when the dosage pumps are shut down
- Provisions exist for preventing the dosage pumps from operating when the RO system is shut down
- If chlorine is used, provisions exist to ensure complete chlorine removal prior to the membranes
- Planned instrumentation allows proper operation and monitoring of the pre-treatment and RO system
- Planned instrumentation is installed and operative
- Instrument calibration is verified
- Pressure relief protection is installed and correctly set
- Interlocks, time delay relays and alarms are properly set
- Provisions exist for sampling permeate from individual modules
- Provisions exist for sampling raw water, feed, permeate and concentrate streams from each stage and the total plant permeate stream
- Pressure vessels are properly piped both for operation and cleaning mode
- Pressure vessels are secured to the rack or frame per manufacturer’s instructions
- Membranes are protected from temperature extremes (freezing, direct sunlight, heater exhaust, etc.)
- Pumps are ready for operation: aligned, lubricated, proper rotation
- Fittings are tight
- Cleaning system is installed and operative
- Permeate line is open
- Reject flow control valve is adjusted in open position
- Feed flow valve is throttled and/or pump bypass valve is partly open to limit feed flow to less than 50% of operating feed flow
