Two of the mostly used methods of removing hardness from water is discussed briefly

1. WATER SOFTENING
Kazi Ismile Hossain
Lecturer,
Department of CE, UCTC

2. Removal of hardness from water.
Hardness is caused by the presence of Ca+2 and Mg+2
ions in water.

3. Methods of Water Softening
Softening
Methods
Chemical
Precipitation
Lime Soda
Ash Method
Caustic Soda
Method
Ion
Exchange

4. Lime Soda Ash Method
All forms of Carbonate and Non Carbonate Hardness can
be converted to the precipitating species by the addition of
lime and soda.

5. Lime Soda Ash Method
.

6. Caustic Soda (NaOH) Process
All forms of hardness can be converted to the precipitating
species by the addition of NaOH.

7. Ion Exchange
.

8. Ion Exchange
.

9. Ion Exchange
Ion exchange process can remove 100% hardness from
water.
But, some hardness is desirable in drinking water.
How to maintain?

10. Ion Exchange