Four Tips for Cleaning a Reverse Osmosis Water Filter

Reverse Osmosis Water Filter Systems, also known as RO systems or hyper filtration systems are amongst the best water purification systems around. This is mainly due to the vast array of water contaminants that these systems are capable of removing. Cleaning a RO Water filter is an important part of the periodical maintenance procedures required for it to give the best results and to avoid serious damages.

1. When to Clean Your RO System

A RO system needs to be closely monitored and values should be noted. Cleaning of the system is highly recommended in three particular instances. The first is when the normalized flux has decreased, even if by a small amount. Another instance is when the normalized salt content of the filter has increased slightly as well as when you notice a decrease in the pressure rise in the pressure container.

The frequency of cleaning should be between 3 to 12 months, according to the fouling that the RO water filter is subjected to.

2. How To Go About the Cleaning Process

As with the frequency of cleaning, the time required for cleaning a RO system varies between 4 to 8 hours, depending on the amount of fouling present. As a rule of thumb, the cleaning process should start off with a low-flow recirculation with filtrated water to remove any clogging and dirt. Then you can introduce the cleaning solution suggested by the manufacturer, for approximately 60 minutes. If the pH changes more than 0.5 pH units, this should be readjusted to the targeted pH value before proceeding. This similar cleaning technique should be used in any subsequent stages. An optional soak and recirculation can be included, always following the manufacturer’s instructions and making sure that the proper temperature and pH is maintained. It is also suggested to apply a low pressure cleaning rinse with filtered water to remove chemical residues form the cleaning skid and RO skid. It is common for the water quality to take from a few hours to a few days to become constant, especially after intensive pH cleanings.

3. Tools Used

A selection of tools is required for optimal cleaning results. Firstly, RO filtered water or at least, soft water, should be used both for cleaning the system and for diluting cleaning chemicals. This detail is often overlooked but it is essential not only for best cleaning results, but also for the longevity of the components of the RO water filter.

Other tools include: a properly sized RO Cleaning Tank, a RO cleaning pump with proper cross flow velocity to scrub the membrane clean, a RO Cleaning Cartridge Filter that clears dirt displaced during the cleaning, a RO Tank Heater or Cooler and a RO Tank Mixer.

Along with these, the use of instrumentation that monitors flow, pressure, tank level and temperature is recommended.

4. Precautions To Keep In Mind When Cleaning Your RO System

Since the RO system involves delicate parts and dangerous chemicals, one should keep in mind a number of precautions in order to avoid damaging the water filter or creating a health hazard. First of all it is very important to follow the manufacturer’s suggested chemical list, dosage, pH values, temperature and contact time guidelines. Also, make sure to use the mildest possible chemical as this will maximize the longevity of the components. Do not mix acids with caustics and always dispose of the cleaning chemicals adequately. Make sure to meticulously rinse the first cleaning solution before introducing the next solution.

Successfully cleaning a RO water filter is important. However, if optimal results are not obtained, the manufacturer or an expert should be consulted in order to make further cleaning sessions more effective.