What is Liqui Deionization?

Liqui Deionization or LDI is a water purification & softening technology that removes ions from water through an electrical field. The technology involves the application of a low voltage electric field in water/liquid using porous electrodes. The impure mineral salts present in water as ions are absorbed on the surface of these porous electrodes, thereby purifying water.

The negatively charged impurities like chloride, nitrate, sulphate, etc. are attracted by the positively charged porous electrodes, whereas, the positively charged impurities like sodium, calcium, magnesium, etc. are attracted by the negatively charged porous electrodes. The porous electrodes are made of carbonaceous materials like activated carbon, graphene, etc. depending on the quality of water to be deionized.

In traditional deionization processes like ion exchange resin deionization, there is a requirement of various ion-exchange chemicals and additional processes for the generation and regeneration of ion exchange resins. In the LDI, the regeneration process involves the removal of the electrical field which is much easier compared to the complex exchange systems.

1Ion Removal

When Water passes between the electrodes, the ions get attracted to opposite charged electrodes. The water void of these salts and metals come out of the system.


With more and more ions sticking to the electrodes, they become saturated – when this happens, the system automatically changes the polarity. The ions sticking to the electrodes fall off.


Water is then flushed between the electrodes and the wasted ions are flushed to drain. The Polarity is reversed back and the Ion removal process (Step 1) starts again.


Reverse osmosis (RO) water purification system is the advanced form of the separation process. A nano-sized pore of RO Membrane filters the liquid. Most of the ions are bigger than the pore size of the RO membrane; hence, affecting the accuracy of the RO system.

Moreover, during the Reverse Osmosis process, the water loses about 95% of its minerals. Thus the health quotient of the water is not optimum. The water obtained post RO process does not contain sufficient minerals and vitamins. There are certain norms laid by government institutions and regulatory bodies for filtered and mineralized water. The by-product of RO does not match the mineral norms laid by these institutions.

Retaining natural minerals is not possible in RO water purifier technology. It can only be increased by mixing high TDS impure water and adding it to low mineral purified water or mixing synthetic minerals. Further, due to its separation character, it rejects around 75% of water during the purification process which is a COMPLETE WATER WASTAGE and a dent in the "SAVE WATER MISSION" of India.

Liqui deionization is a modern method of water purification. It retains a considerable amount of natural minerals in the water. It functions by adjusting the ions through a process called ion exchange and maintains the taste & mineral content in the water.

One of the greatest advantages of LDI is that it is zero wastage. THE LDI systems do not have any rejection or wastewater outlet. It operates with a self-controlled backwash system. This system consumes about only 20% of the water. Thus, one gets maximum purified water.

LDI Technology is versatile and multipurpose as it purifies & balances ions and also removes the hardness from the water. It works as a water softener as well. The automatic next-generation LDI works beyond the traditional process of resin-based softening process. The LDI functions independently and does not demand frequent resin regeneration.