As an essential resource for human survival, life and production activities, the importance of water is obvious, but the increase in industrial pollution has also made the removal of impurities in the water particularly important. As a part of the softened water in the water treatment process, the softened water equipment plays an important role. And what is the principle of water softening equipment? How does it convert hard water into soft water?
The softening principle of hard water
Water softeners, in terms of operation and use, are divided into two categories: electronically controlled automatic type and manual clock-controlled type, both of which use ion exchange principles. By replacing the calcium and magnesium ions in the source water, the water that flows out is softened water with extremely low hardness without calcium and magnesium ions. When the ion resin absorbs a certain amount of calcium and magnesium ions, it must be regenerated-soak the resin layer with saturated salt water to replace the calcium and magnesium ions on the resin to restore the exchange capacity of the resin and discharge the waste liquid sewage. The most advanced automatic control system is to automate the whole process of softening, backwashing, salt absorption, slow washing, quick washing, and salt tank water injection.
Operation mode of water softener and resin regeneration
The circulation process of the electronically controlled full-automatic and manual clock-controlled water softener consists of the following steps:
1.Operation: Under a certain pressure and flow rate, the source water flows through a container (water softener) containing ion exchange resin to exchange the exchangeable Na+ contained in the resin with cations (Ga2+, Mg2+, Fe2+, etc.) in the water. The content of Ca2+ and Mg2+ ions in the effluent of the container is greatly reduced to meet user requirements.
2.Backwashing: The resin becomes invalid after adsorbing a certain amount of calcium and magnesium ions, and backwashing with water from the bottom up before regeneration. There are two purposes of backwashing. One is to loosen the compressed resin layer during operation by backwashing, which is conducive to the full contact of resin particles with the backwash liquid. The other is to accumulate suspended solids on the surface of the resin during operation and some broken resin. The particles are also removed with the backwash water flow. In this way, the water flow resistance of the exchanger will not become larger and larger. In order to prevent the complete particles of resin from being washed away during backwashing, when designing the water softener, a certain amount of backwashing space is left on the resin layer, and the greater backwashing strength is. The larger the backwash space. The quality of backwash directly affects the regeneration effect.