The role of Antiscale in filtration systems, reverse osmosis water

One of the most important problems in water purification systems, reverse osmosis, create deposits on the surface of the Filter Membranes is. In the event of failure to control this issue, saw a decrease in system performance and lifetime Membarne will be that the cost of direct and indirect significant for the consumer will be followed.

One of the most important actions that, in order to prevent sedimentation of the water on the membrane, can be used, the use of “Antiscale” is. Select and inject the correct Antiscale, the most important things to consider is that in the design and governance of a water filtration system, reverse osmosis (RO) can be considered to have.

Antiscale usually to one of the three methods under the act:

– Increase the threshold solubility (Threshold Inhibition) – be a solution of keep the Salt supersaturated in water

– Change the shape of the crystal (Crystal Modification) – ability to change the shape of the crystals and turning them into particles, soft and non-sticky

– Disperse (Dispersion) – with the induction of negative charge to the particles, etc. from sticking them to each other and forming the mass, the larger the stop.

Antiscale are usually alone or sometimes along with acid in a water filtration system, reverse osmosis water are used. The use of acid in the injection ofAntiscale, because of the decline of the index LSI to control the deposition of calcium carbonate and also control the deposition of calcium phosphate and fluoride of calcium. Antiscale commonly available in the market, mainly in controlling the deposition of calcium phosphate, as well as precipitated calcium carbonate index (LSI higher than the number 2, the problems that they have. Because of the injection of acid in reverse osmosis system, reducing the index LSI to acceptable it is. Usually, the acceptable range indicator LSI for the effectiveness of appropriate Antiscale, between the numbers 1 and 2.

It should be noted that many manufacturers raised the membrane in the World. condition, warranty, membrane him. injection of Antiscale perfect and also being smaller index LSI of the number 1/8 title. Therefore, if the index LSI incoming water to the membrane, over 1/8 in … could be the acid injection it below 1/8 him to take advantage of the warranty, a membrane there be.

Acids that to reduce the index LSI are used, etc., mostly of the type “hydrochloric acid” or “sulfuric acid” are. But the point regarding the use of sulfuric acid, you must bear in mind is that the injection over the size of this acid increases the likelihood of sediment, with the base of the sulfate on the surface of the membrane can be. Moreover, the use of hydrochloric acid instead of sulfuric acid, etc., the more attention and advice.

In the above description, a few times, from the conceptual to the name of the index, LSI talking that was necessary to appear a short description in this regard will be provided.

Index Saturarted Longelier or LSI., the abbreviation for the word Langelier Saturation Index, which is the direction of a little amount of the tendency of water to sediment or corrosion etc. is defined. The amount of indicator LSI to five parameter “rate of temperature”, the “pH” and “TDS”, “a tough Calcium” and “alkalinity water” depends. Of course, the use of the index LSI for water that is used that TDS them under 10,000 ppm.

The method of calculating the exact LSI, in the scope of this article, this does not fit. In the event that the number obtained for the indicator Saturarted Longelier higher than Zero, The … represents the tendency of water to the sedimentation and, if that rate is less than zero it. expresses a desire corrosion in the water. The table below characteristics, more of the water, with different numbers LSI shows:

Weather conditions

Index LSI

The tendency to sedimentation is very intense


The tendency to sedimentation too much


Sedimentation much


Sedimentation typical

Sedimentation style+0.2
Water stable (without sediment)0.0
Water without sediment. little tendency for corrosion (dissolve the salts in your own)-0.2