Demineralization or Deionization is the process of removing mineral salts from water by using the ion exchange process. With most natural water sources it is possible to use Demineralization and produce water of a higher quality than conventional distillation.

The following ions are widely found in raw waters:
Calcium (Ca2+) Chloride (Cl-)
Magnesium (Mg2+) Bicarbonate (HCO3-.)
Sodium (Na+) Nitrate (NO3-)
Potassium (K+) Carbonate (CO32-)
 Iron (Fe2+) Sulfate (SO42-)

There are three ways in which ion-exchange technology can be used in water treatment and purification: first, cation-exchange resins alone can be employed to soften water by base exchange; secondly, anion-exchange resins alone can be used for organic scavenging or nitrate removal; and thirdly, combinations of cation-exchange and anion-exchange resins can be used to remove virtually all the ionic impurities present in the feedwater, a process known as deionization. Water deionizers purification process results in water of exceptionally high quality

Shubham manufactures a wide range of custom-built Demineralizing plant for industrial process water applications, with inherent design to conserve water, and save costs. They are available in different sizes and materials, manually operated or fully Automatic, & ready to install & are available as standard models or custom built versions for specific needs.

Operating Principle
Further high purity water can be achieved by Mixed Bed Deionisers, which are designed to produce high purity treated water. They can be used as polishing units after two bed DM Plant to obtain high purity water. Mixed Bed Deionisers are single column units, filled with strongly acidic cation and strongly basic anion exchange resins mixed together.

There are four distinct stages in the operation of Deionisers
  • Service
  • Backwashing
  • Regeneration
  • Rinse/remix

Service
In the Service cycle the water enters the vessel and passes through the Resin bed of the respective exchanger.

Backwashing
After the resins are exhausted, the bed is backwashed. Backwashing is carried out by a uniform upward flow of water through the resin bed. The backwash step expands the resin bed releasing any entrapped particulate matter & removes the channeling in the resin column if occurred during the service cycle.


Regeneration
When the ion exchange resins loose all the exchangeable ions, they require regeneration to restore them back to hydrogen or hydroxyl form depending upon whether they are cation or anion resins. To achieve this 4 - 5% concentrated solution of Hydrochloric acid is used for cation resin and a 4% - 5% concentrated solution of caustic soda for anion resin. Sulphuric acid can also be used for Cation Regeneration but the concentration of acid during injection must be kept at minimum, such as to prevent calcium sulphate precipitation on the resin.

Rinse
The final stage of regeneration is to rinse the resins of excess regenerant

Advantages
  • Easy to install & operate
  • Complete Assembly with backwash ®eneration equipment
  • Produces DM water of high purity
Shubham Inc. All Rights Reserved.