Membrane Cleaning Process
How it Works
Cleaning RO Membranes is truly a cost-effective option versus replacing them. Did you know that most commercial and industrial RO membranes will last between 3-5 years? During that 3-5 year mark, you will most likely need to clean your RO membranes to keep them at like-new performance.
Virtually all the major membrane manufacturers agree on the following statements
Reverse Osmosis membranes should be cleaned when normalized flow decreases by 10% from the initial acceptance test conditions.
Reverse Osmosis membranes should be cleaned when the overall pressure drop increases by 15% over the initial acceptance test conditions.
These two simple, explicit statements often go ignored, even though it has been demonstrated that the optimum cleaning response is achieved when these guidelines are followed. It can be difficult to recover performance if the system operates in a fouled condition for an extended period. Operating in a fouled condition can also cause irreversible damage to the membrane performance, which would require costly replacements if left unchecked.
Some problems can occur with improper usage of the CIP system (Clean in place) or perhaps it is not having the right cleaning solutions. There are plenty of options when it comes to cleaning your RO membranes. The best way is determined by analyzing your water and your system operations.
A periodic cleaning can be performed at just the right time, flow rate, and temperature, and it can still fail if the chemistry applied is not appropriate for the specific foulant. For that reason, it is wise to spend some time before a chemical cleaning is needed to determine your most likely membrane fouling.
For example, increased pressure drops in the first stage indicate colloidal from either inorganics or organic fouling in a system, and it can also indicate bacterial fouling. This type of fouling tends to benefit from a low pH soak followed by an alkaline cleaning. If the final stage pressure drops are elevated, it is an indication of mineral deposition. To properly address this type of fouling, it is necessary to know what minerals are most likely to deposit. System projections or antiscalant projections can be useful here, as can a new mineral analysis on both the feed and concentrate. These types of deposits may require low-pH cleaners for carbonate scales or alkaline chelant cleaners for sulfate scales.
Many Industrial Reverse Osmosis Systems are equipped with a CIP or Clean in Place system. This will allow you the ability to clean your Reverse Osmosis system onsite. If your system is not equipped with a CIP System Complete Water Solutions can provide and install a system that will work with your existing Industrial RO System.