Hardness of Water

1
Hardness of Water

• DEFINITION
• The property of water to form an insoluble
  curd with soap instead of lather. In other words
  it is the soap destroying property due to the
  presence of Bicarbonates, Sulphates and Chlorides
  of Calcium and Magnesium.

2
Types of Hardness

• TEMPORARY HARNESS
• It is due to the presence of Bicarbonates
  of Calcium Magnesium and can be removed by
  boiling.
• PERMANENT HARDNESS
• It is due to the presence of Sulphates,
  Nitrates and Chlorides of Calcium Magnesium.

3
Measurement of Hardness

• Hardness of water is expressed / measured in
  terms of milli equavilant / litre
• 1 milli-equavilant 50 mgs.of CaCO3 / litre

4
Classification of Hardness

• Soft water-------------------- 1 m.Eq. / litre
• Moderately hard water--- 1-3 m.Eq. / litre
• Hard water----------------- 3-6 m.Eq. / litre
• Very hard water---- 6 and gt 6 m.Eq. / litre

5
Advantages of Hardness

• Reduced prevalence of,
  1.Arteriosclerotic heart disease
• 2. Degenerative heart disease
• 3. Sudden death due to Cardiac arrest
• 4. Hypertension and
• 5. Tetny

6
Disadvantages

• Are in the form of economic loss of a community
  and a country at large such as
• More consumption of soap detergents
• More consumption of fuel due to scaling formation
  in the boilers in industries
• Discoloration of foods
• Short life of clothes due to deposition of salts
  in fabrics
• Disturbance of dyeing process
• High prices of products
• Decreased life of cisterns and Pipes

7
Removal of Hardness

• A. FOR TEMPORARY HARDNESS
• Boiling
• Addition of Lime
• B. FOR PERMANENT HARDNESS
• Addition of Lime
• Addition of Sodium Carbonate
• Base Exchange method / Permutit Process