Hardness
Calcium and magnesium salts deposit on the membrane on the concentrate side.
By problem
Scale and Fouling on a Reverse Osmosis Membrane
A reverse osmosis membrane leaves the salt behind. When the remaining hardness and silica pass saturation, scale forms on the membrane. Organic dirt and biofilm are a separate fouling. The antiscalant and the dosage are selected from the feed water analysis and the projection report.
Antiscalants · What is an antiscalant, and how do you select it? · Scale in a steam boiler
Why does it happen?
Silica
High silica creates a scale risk that a standard antiscalant does not cover.
Recovery
As recovery rises, the concentrate gets saltier and deposition gets closer.
Organic dirt
Oil, biofilm and organic load are a fouling that is different from mineral scale.
What damage does it cause?
Signs
- Permeate flow falls at the same pressure.
- Membrane differential pressure rises.
- Product-water conductivity gets worse.
- Feed water hardness or silica is high.
- After a clean, the efficiency falls again in a short time.
How do you solve it?
Antiscalant
It is dosed before the membrane. If silica is high, select the product for silica.
Projection
The dosage is set from a projection report of the feed water analysis.
Pre-treatment
Filtration, and softening when it is required, lowers the load that enters the membrane.
Cleaning
Mineral scale that has formed is removed with an acidic cleaner. Organic dirt and biofilm are removed with an alkaline cleaner.
Our recommended products
The antiscalant prevents scale. C mec cleaners remove dirt that has already formed. This page does not give a dosage.
C scalant 1085
NSF-approved antiscalant
It is an NSF approved antiscalant. It protects reverse osmosis membranes against scaling and fouling.
C scalant 2005
NSF-approved antiscalant for drinking water
It is an NSF approved, high-concentration antiscalant. It protects reverse osmosis membranes against scaling and fouling, also at high hardness.
C scalant 6090
Antiscalant for silica
It is a special antiscalant for feed water with a high silica content. It protects reverse osmosis membranes against silica scale.
C scalant 6080
High-concentration antiscalant for silica
It is a high-concentration antiscalant for feed water with a high silica content. It protects reverse osmosis membranes against that scaling risk.
C mec 102
Acidic membrane cleaner
It is an acidic membrane cleaner. It removes scale and mineral deposits from reverse osmosis membranes.
C mec 100
Organic acidic membrane cleaner
It is a membrane cleaner based on organic acid. It removes mineral deposits from reverse osmosis membranes.
C mec 200
Alkaline membrane cleaner
It removes the organic fouling, biofilm and oil residues that collect on reverse osmosis membranes.
C-mec 17
Membrane disinfectant
It is a membrane disinfectant for the periodic disinfection of reverse osmosis membranes.
Frequently asked questions
Is an antiscalant the same product as a membrane cleaner?
No. An antiscalant protects the membrane against scaling and fouling. C mec cleaners remove mineral deposits, organic dirt or biofilm that has already formed.
Which antiscalant do you select when silica is high?
C scalant 6090 and C scalant 6080 protect the membrane against silica scale when silica is high. C scalant 6080 is more concentrated than C scalant 6090.
What sets the antiscalant dosage?
The dosage is set from a projection report of the feed water analysis. Hardness, silica and recovery are read together.
When do you clean the membrane?
Clean the membrane when permeate flow falls and differential pressure rises. C mec 102 or C mec 100 removes mineral scale. C mec 200 removes organic dirt and biofilm. C-mec 17 is a separate job: it disinfects the membrane on a schedule.
We help you select the antiscalant for your membrane from the water analysis
Send your feed water analysis. Our technical team will reply with a product for the hardness, the silica and the recovery.
We reply to quote requests within 12 hours.