The impurities in water lead to the salt formation in the Reverse Osmosis unit, which results in scaling. The RO Membrane Antiscalant chemicals help to reduce scale and fouling inside the membrane, irrespective of the water source. However, treatment from ordinary Antiscalant reduces scaling, but the use of good Antiscalant improves the efficiency and fights against a wide range of scale-forming substances.
What is Antiscalant ?
There are a vast number of chemicals that one can use as Antiscalants and dispersants to improve the overall efficiency of RO and nanofiltration system. Antiscalants reduce the formation of compounds inside water and mineral salts that leads to scaling. Most of these chemicals constitute human-made organic polymers. The molecular weight of the polymer starts from 2000 to 10,000 Da. Antiscalant technology was initially gleaned from the processes used in cooling water and boiler water.
The different Antiscalant chemistries offer different results and hence efficiency. It depends upon the type of polymer. However, every polymer is different, and you should use it with caution.
Antiscalants that you can make from polyacrylic acid:
These Antiscalants are vulnerable to the formation of foulant that quickly spreads on the membrane surface if they contain a high amount of iron. The foulant adds additional feed pressure, but you can easily clean it with the help of low PH cleaning.
Antiscalants that is anionic like polyacrylic acid:
When the Antiscalant is anionic and cationic, filtering aid is taken during the pretreatment. It is a very sticky fluid that produces feed pressure requirements, and it becomes difficult to clean it.
In earlier times, Antiscalant like sodium hexametaphosphate were used, but it had its limitation. Hence, now a new range of Antiscalants have become popular.
Where the Antiscalant technology finds its application?
This pretreatment system reduces the scale formation and finds its application in feed water sources, like brackish, waste-water and seawater. This technology provides efficiency against, the common foulants like calcium carbonate, strontium sulfate, silica and other organic compounds.
What are the features and benefits of Antiscalant chemicals?
The Antiscalant offers several benefits like;
- It helps to control the scale formation inside RO like silica, calcium carbonate, barium sulfate and silica.
- It is compatible with the RO process and Nanofiltration membrane.
- It helps to clean the membrane surface by reducing particulate foulants.
- RO system can run efficiently with the help of Antiscalant that translates into low operating cost.
- Antiscalant is highly suitable for full pH range products.
However, it is essential to maintain the right level of Antiscalant. Under-dosing can result in scaling or fouling. Overdosing can lead to the deposit of Antiscalant on the membrane, thus increasing the fouling problem. A regular maintenance and services can protect a significant return on investment by extending your RO system life, preventing membrane damages and life of membranes.