QUESTION
Objective Question
The alum added as a coagulant in water treatment functions when the raw water is
Answer
( Option C)
Alkaline with high turbidity
Solution
Alum reacts with alkalinity present in water and result in formation of sticky gelantinous precipitate of aluminium hydroxide
which attract fine suspended impurities over its surface, thus grow in size and gets easily settled in the following
sedimentation process.
For sweep computation to work water should have high alkalinity and high turbidity.
