_Membrane Cleaning Tips
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Effective membrane cleaning involves proper procedures combined with chemistry that is specifically formulated to remove the target foulant. One without the other can result in ineffective cleaning.
Reverse Osmosis Membrane Cleaning
Use proper chemical dilutions
When diluting cleaners, take into consideration the total volume of water in the system including: tanks, pipes and/or hoses and vessels. Table 1 gives a guide to membrane vessel volumes.
Use proper flow rates
The velocity of the solution across the membrane surface is critical. Clean 4” membranes at 10 to 12 gpm and 8” membranes at 35 to 40 gpm. Full-fit membranes require higher flow rates, 60 gpm for an 8” element.
Always clean membranes in parallel
If necessary, separate the vessels to achieve this. Never clean the vessels in series as it is difficult to ensure proper flow rates and pressures.
Minimize cleaning pressure
Clean at pressures less than 60 psig. This will minimize or eliminate foulants being pulled down to the membrane surface by water permeating during the cleaning procedure.
Heat the cleaning solution
Heat to the maximum temperature allowed by the membrane manufacturer.
Additional Tips
Use only DI or RO permeate water to dilute cleaning solutions.
Reduce cleaner foaming by placing return lines below the water level in the CIP tank.
Use a combination of low and high pH cleaning solutions.
Recirculate the cleaning solution for a minimum of 45 minutes.
Membrane Cleaning Tips
Effective membrane cleaning involves proper procedures combined with chemistry that is specifically formulated to remove the target foulant. One without the other can result in ineffective cleaning.
Reverse Osmosis Membrane Cleaning
Use proper chemical dilutions
When diluting cleaners, take into consideration the total volume of water in the system including: tanks, pipes and/or hoses and vessels. Table 1 gives a guide to membrane vessel volumes.
Use proper flow rates
The velocity of the solution across the membrane surface is critical. Clean 4” membranes at 10 to 12 gpm and 8” membranes at 35 to 40 gpm. Full-fit membranes require higher flow rates, 60 gpm for an 8” element.
Always clean membranes in parallel
If necessary, separate the vessels to achieve this. Never clean the vessels in series as it is difficult to ensure proper flow rates and pressures.
Minimize cleaning pressure
Clean at pressures less than 60 psig. This will minimize or eliminate foulants being pulled down to the membrane surface by water permeating during the cleaning procedure.
Heat the cleaning solution
Heat to the maximum temperature allowed by the membrane manufacturer.
Additional Tips
Use only DI or RO permeate water to dilute cleaning solutions.
Reduce cleaner foaming by placing return lines below the water level in the CIP tank.
Use a combination of low and high pH cleaning solutions.
Recirculate the cleaning solution for a minimum of 45 minutes.
Membrane Cleaning Tips