Technical Services

T: +27 (0) 21 855 2553, F: + 27 (0) 21 855 0662, E: az.oc.retawsunev@ofni

SABS Standards

In South Africa at present, no protocol has been established yet to test purifiers in order to provide manufacturers or suppliers the opportunity to obtain a SABS mark of approval.

At best the water that is obtained from a purifier can be submitted for biological and chemical tests to ensure that it conforms to the standards for domestic water in South Africa. Such a test does not afford a supplier the right to claim SABS approval of a purifier.

Steam distillation | Carbon filtration | Ion exchange | KDF | Ultra Violet lights | Reverse Osmosis

Steam distillation

Water is heated to boiling and the steam is collected and cooled.  This is the surest way to ensure that there are no impurities in your water.  This method however is very slow, expensive and uses power.  The distillation process does not remove all organic compounds; the water must therefore go through carbon filters before use.

Carbon filtration

This is the most popular system use to remove pollutants, using granular activated carbon (GAC) absorption.  Not only are GAC’s important in absorption, but they also improve the aesthetics in producing high quality water-taste, colour and odour.

 A GAC filter does not kill or remove bacteria or viruses.  Organics are of great concern in water treatment because thy react with many disinfectants, especially chlorine and cause the formation of DBP’s which include THM’s.  These DBP’s can add to poor taste and are often carcinogenic and, therefore highly undesirable.

 Activated carbon is manufactured by selective oxidation of a carbon containing material to produce a highly porous structure.  Almost any material containing carbon can be used.  Materials currently used are: coal, lignite, wood, peat, bone char, coconut shell, rice, soybean hulls, spent sugar cane pulp, shells of peanuts, walnuts and pecan nuts.

Upon contact with water containing soluble organic materials, GAC selectively removes the materials by absorbsion.

Ion exchange

Ion exchange rids water of dissolved minerals and toxic metals, but is less effective at removing organic molecules.  Charged particles in the filter exchange themselves for the charged particles in the water.  You could end up with harmful levels of sodium in the purified water.  This method also corrodes pipes and cause high levels of copper, iron and lead in drinking water.

KDF Process Media

KDF 55 process medium is a high-purity, granulated copper and zinc based alloy that treats water through a process of redox (oxidation and reduction)

The combination of Copper and Zinc creates an electro-chemical reaction. During this reaction, electrons are transferred and new compositions are created. Some harmful contaminants are changed into harmless components. Free chlorine for instance, is changed into harmless water-soluble chloride, which is then carried harmlessly through the water supply. Similarly, some heavy metals such as copper, lead and mercury react to plate out onto the medium's surface, thus being effectively removed from the water supply.

Benefits of KDF process media:

  • Significantly extends the life of Granular Activated Carbon while protecting the carbon bed against fouling by bacterial growth.
  • KDF medium helps control microorganisms by creating an environment that is deadly to some microorganisms and that interferes with the ability of many other microorganisms to function.
  • It effectively removes Chlorine, Iron and Hydrogen Sulfide.

Ultra violet light

Ultraviolet light kills microorganisms, but have no effect on chemical toxins.

Reverse Osmoses (RO)

The RO system removes minerals and toxic heavy metals like lead, along with organic contaminants.  Water is forced through an osmotic (or semi permeable) membrane.  Bacteria are blocked out and can’t grow on the filter.  This process is slow and wastes a lot of water.  RO water is very corrosive to pipes.

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