We, watermark, holding our registered set-up at Earpur, Ashulia Road, Savar Industrial Zone, Dhaka, are pleased to introduce expert off-site RO Membrane Cleaning Services for industrial and commercial applications, complying technical guide lines of Hydranautics Tri Sep of USA.

Our Purposely designed off-site membrane cleaning facility and cleaning process using effective cleaning regiment with customized cleaning procedure will help bring your membrane with improved performance to maintain productivity, longer and a complete cleaning report is provided to our customers upon delivery showing how effective the cleaning was in restoring flow and salt rejection.


Scope :

At present, we can provide cleaning service for 80” dia and 40” length membranes. Facility for other sizes may be introduced upon demand.

When to clean your RO membrane :

Membrane cleaning is periodically required for all RO system membranes. It is essential to clean RO membranes at an early stage of fouling. It is often difficult to clean excessively fouled membranes and irreversible damage may occur during the cleaning process. Cleaning is strongly recommended when one or more of the following parameters change by 10 – 15% after data normalization:

  • Decrease in normalized permeates flow.
  • Increase in feed pressure
  • Increase in pressure drop
  • Decrease of about 0.5% salt rejection.

If any of the above performance parameters deteriorates by more than 30%, it may be very difficult to recover plant performance by routine cleaning practices.

In general, RO membrane cleaning is to be carried out every 3 to 12 months, depending upon the foulants in feed water.

While most RO and NF (Nanofiltration) system may have built in cleaning system but the efficiency of those cleaning largely varies as membranes are arranged in series making it difficult to flush out foultant easily from system. Also in most cases the onsite cleaning system are under designed making them ineffective forcleaning in the long term.

In offsite cleaning we provide one membrane element clean/housing which sufficient amount of cleaning solution, specific pressure and pH condition according to each different membrane model, manufacturer, the overall performance is much improved.

Benefits of cleaning :

  • Increases membrane life
  • Cost effective
  • Reduces power and water cost
  • Increases output and quality