Demineralized water treatment equipment: introduction to ion exchange method

Two common ion exchange methods are hard water softening and deionization. Hard water softening is mainly used as a pre-treatment procedure to reduce water hardness before reverse osmosis (RO) treatment. The spherical resin in the softener softens the water by exchanging two sodium ions for one calcium ion or magnesium ion.

The ion exchange method is to filter the raw water with spherical resin (ion exchange resin), and the ions in the water will be exchanged with the ions fixed on the resin.

Ion exchange resins use hydrogen ions to exchange cations and hydroxide ions to exchange anions; cation exchange resins made from sulfonate-containing styrene and divinylbenzene exchange hydrogen ions for various cations encountered (such as Na+, Ca2+, Al3+). Likewise, anion exchange resins made from styrene containing quaternary ammonium salts will exchange hydroxide ions for various anions encountered (eg, Cl-). The hydrogen ions released from the cation exchange resin combine with the hydroxide ions released from the anion exchange resin to form pure water.

Anion and cation exchange resins can be packaged separately in different ion exchange beds, divided into so-called anion exchange beds and cation exchange beds. The cation exchange resin and the anion exchange resin can also be mixed together and placed in the same ion exchange bed. Either way, when the resin has exchanged the hydrogen and/or hydroxide ions on the resin with charged impurities in the water, it must be “regenerated”. The regeneration procedure is just the opposite of the purification procedure, using hydrogen ions and hydroxide ions for regeneration to exchange impurities attached to the ion exchange resin.

If the ion exchange method is used in combination with other water purification methods (such as reverse osmosis, filtration and activated carbon adsorption), the ion exchange method will play a very important part in the entire purification system. The ion exchange method can effectively remove ions, but it cannot effectively remove most of the organic matter or microorganisms. The microorganisms can attach to the resin and use the resin as a medium, so that the microorganisms can grow rapidly and generate heat. Therefore, it needs to be designed and used in conjunction with other purification methods.

Xi’an CHIWATEC Water Treatment Technology is a high-tech enterprise specialized in various water processing devices. Aside from these individual products, which cover a number of types and series, we can also help with related comprehensive engineering projects. Thanks to our hard work and dedication upon our founding, we are now one of the fastest-developing water treatment equipment manufacturers in Western China.

Further reading：

• Softened water treatment equipment: introduction of ion exchange method
• Advantages of EDI technology compared with hybrid ion exchange technology
• Introduction to the working principle and pretreatment of ion exchange resin system
• Introduction to the characteristics and application fields of ion exchange resin ultrapure water preparation process
• Ion exchange resin, mixed bed ion exchange resin
• Ion exchange resin and mixed bed ion exchange resin
• Ion Exchange Filter, Ion Exchange Resin, Ion Exchanger
• What is the ion exchange method? What is the working principle of the ion exchange method?
• Other supplementary knowledge of ion exchange resin
• Physical properties of ion exchange resin
• Adsorption selectivity of ion exchange resin
• Physical structure of ion exchange resin
• Composition of ion exchange resin matrix
• Introduction to ion exchange resin
• Introduction to the application fields of ion exchange resins
• What are the basic types of ion exchange resins?
• Ion exchanger capacity of ion exchange resin
• Ion exchange soft water equipment
• Issues that should be paid attention to in ion exchange operation and regeneration
• Storage of ion exchange resin
• Application of ion exchange resin
• Matters needing attention in using ion exchange resin
• Ion exchange resin classification
• Questions and answers about ion exchange water treatment equipment
• Overview of ion exchange pure water equipment
• Characteristics and application of ion exchange resin
• Features of ion exchange resin
• Technical requirements for automatic control sodium ion exchanger
• Technical terms and definitions of automatic control sodium ion exchanger
• Industrial wastewater treatment equipment-ion exchange membrane separation equipment
• What is ion exchange resin? What is the preservation method and regeneration method?
• Factors affecting the exchange capacity of the fully automatic sodium ion exchanger
• C100E ion exchange resin