TREATMENT OF WATER (Basic Definition and steps )

Water treatment is the process that makes water more acceptable for a specific end–use, mostly for drinking. During treatment the impurities present in water are not removed to zero but to a level which will not be harmful for intended use as per the standard.

Treatment process of water generally involves following steps:

i)          Screening: To remove all large suspended and floating matters like leaves, fish, dead bodies, tree branches bushes etc. and generally provided at intake point.

ii)         Plain sedimentation: To settle down coarse and heavy suspended particles such as sand, silt etc and few colloidal particles through the force of gravity.

iii)       Sedimentation with coagulation: To remove the fine suspended particles and colloidal particles.

iv)        Filtration: To remove microorganisms, very fine suspended particles and colloidal impurities escaped from the sedimentation tank. It mainly involves the process of passing the water in a filter media, mostly sand.

v)         Disinfection: To kill the pathogenic microorganisms present in water.

vi)        Softening and hardening: To maintain hardness and softness.

vii)      Other miscellaneous: Softening of water, aeration of water, removal of color, odor, taste, iron and manganese etc. 

Typical Layout of water treatment plant

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Water Supply by Dr. BC Punmia