chap 10

Question 1

10.1a. factors in the Stoke equation are used to decrease te time needed to remove TSS

Answer 1

• Coalescence: the diameter of particles
• inclined plane settlers: particles falling distance
• tube settles that use the waste heat from another process : the viscosity of the water
• centrifugation: the gravitational constant

Question 2

10.1f. Adv to have a shallow stream running up an inclined plane settler

Answer 2

shorter falling distance - less time will be required

Question 3

10.2b. the particle in a depth filter must match the distribution of sizes of the TSS that is to be separated

Answer 3

2 # densities and size ranges are used for the 2 media then after fluidization, the settling rates will result in separation of the two materials (eg. fine GAC and course silica sand)

Question 4

10.4c what will done to waste stream from a depth filter if there is no possibility of deep well disposal

Answer 4

remove the water mechanically so as to reduce the cost of landfill

Question 5

10.3a. A sludge blanket clarifier:

Answer 5

• Coagulation: rapid mix
• flocculation: slow mix
• stoke law: settling

Question 6

10.3a. Kinetic of the process

Answer 6

• rapid mix zone: agitation serves to improve the chance of charged colloidal particles meeting the coagulating agents
• slow mix: the floc is mixed to improve the chance of the different particles forming the floc
• the rates are set that coagulation occurs before flocculation
• sedimentation is also rate controlled process