enki products
- Media Filters
- Activated Carbon Filter
- Calcite Filter
- Horizontal Pressure Sand Filter
- Softener
- Brackish Water Reverse Osmosis
- Membrane Cleaning Unit (CIP)
- CO2 Degasser
- Mixed-bed Ion Exchanger
- Industrial Ultrafiltration
- Cooling Water Filtration
- Odor Removal Systems
- Package Water Treatment Plant
- Disinfection Unit
- Sewage Treatment Plant STP
- Containerized Reverse Osmosis
- Membrane Bioreactor (MBR)
- Sea Water Reverse Osmosis
- Demineralizers (Ion Exchanger)
- Electrodeionization (EDI)
- Chemical Dosing Unit
- Iron Manganese Filter
- Price List
- Dosing / Storage Tank
- Self Cleaning Filter TEKLEEN
WATER HARDNESS
Water is an very good solvent and readily dissolves minerals it comes in contact with. As water moves through soil and rock, it dissolves very small amounts of minerals (like Ca+2 and Mg+2) and holds them in solution.
Water hardness is defined the sum of equivalent concentration of the Calcium and Magnesium ions in water.
The classification of water according to hardness is given in below table
mg Ca+2/l |
mg CaCO3/l |
French Degrees |
German Degrees |
Hardness |
<30 |
<75 |
<7.5 |
<4.2 |
Very soft |
30-50 |
75-125 |
7.5-12.5 |
4.2-7.0 |
Soft |
50-100 |
125-250 |
12.5-25.0 |
7.0-14.0 |
Moderate hard |
100-150 |
250-375 |
25.0-37.5 |
14.0-21.0 |
Hard |
>150 |
>375 |
>37.5 |
>21.0 |
Very hard |
Forms of Hardness
There are two forms of hardness: temporary and permanent. Temporary hardness is the portion of the total hardness that is associated with alkalinity. Permanent hardness is all of the rest. The term ‘temporary hardness’ is a result of the reversibility of the calcium carbonate precipitation reaction with heat. Heating a solution ‘temporarily’ precipitates the hardness; cooling re-dissolves it. Permanent hardness, on the other hand, is not removed by heating.
Advantages of Hardness Removal
- Smaller amount of dish washing and laundry detergent is needed.
- Reduced mineral deposits in plumbing, water heaters, and on pots and pans.
- Fewer water spots on air-dried dishes and glassware.
- Hair and skin will often feel softer after bathing or washing.
What are the health effects of Hardness?
Hardness does not pose a health risk. In fact, calcium and magnesium in your drinking water can help ensure you get the average daily requirements for these minerals in your diet. There are no Standard for Hardness.
Hardness Removal Methods
- Ion exchange softening
- Reverse-osmosis
- Nanofiltration
- Electrodialysis
- Distillation
- Lime Soda Process