Coagulation and flocculation

Question 1

Coag aids add

Answer 1

Density to slow settling floc and add toughness to floc so they will not break up during mixing and settling

Question 2

Importance of floc speed

Answer 2

If flocculator speed is too slow short circuiting may occur

Question 3

Jar test when

Answer 3

80% settled in less than 2 minutes floc is too heavy

Question 4

(3) uses of coag aids

Answer 4

1. Lime
2. Weighting agents
3. Polymers
   
   • cationic +
   • anionic -
   • nonionic

Question 5

Baffles

Answer 5

prevent short circuiting and direct flow

Question 6

Inlet should be designed to

Answer 6

Minimize high flow near bottom

Question 7

Weirs have

Answer 7

V notches at every foot