Coagulation/flocculation

Question 1

what is coagulation/flocculation

Answer 1

Coagulation flocculation is a treatment process that removes non-settlable and colloidal particles from water.

Question 2

Overview on colloidal particles

Answer 2

Colloidal particles carry surface charges around it, which make it in suspension in water thus it doesnt settle.The system is considered to be stable.

Question 3

What is coagulation

Answer 3

Coagulation is the addition and rapid mixing of a coagulant which result in the destibilazation of the colloidal and the remainig suspended particles which cause the initial aggregation of the suspended particles.

Question 4

What is flocculation

Answer 4

Flocculation is slow stirring of water to allow further aggregation of the coagulated particles to form a flocc.

Question 5

Eta potential represents

Answer 5

a high electrokinetic potential will cause stability of molecule

Question 6

Zeta potential represents

Answer 6

a low electrokinetic potential will cause instability of molecule

Question 7

Upon addition of coagulant three reactions could occur

Answer 7

refer to booklet

Question 8

Types of Coagulant

Answer 8

We have five types of coagulants based on PH
PH 4to7 we add Aluminum sulfate Al2(SO4)3
PH 8.5 and above we add Ferrous sulfate FeSO4
pH 3.5 to 6.5 and above 8.5 we add Ferric chloride FeCl3
pH 3.5to7 and above 9 we add Ferric sulfate Fe2(SO4)3
pH above 10.5 we add Magnesium Hydroxide Mg(OH)2

Question 9

Derivation of mean velocity gradient G

Answer 9

Refer to booklet