Deck 9: Sewage Sludge and Treatment Processes

Question 1

From which of the following methods can toxic chemicals be removed?

A)Sorption
B)Adsorption
C)Absorption
D)Dewatering

Answer 1

Sorption

Question 2

What is the term used for reuse of sewage sludge?

A)Compost
B)Solids
C)Biosolids
D)Sludge

Answer 2

Biosolids

Question 3

In which year was the term Biosolids introduced?

A)1990
B)1995
C)1998
D)2000

Answer 3

1998

Question 4

What is the first step in the sewage treatment process?

A)Dewatering
B)Thickening
C)Phosphorus recovery
D)Digestion?

Question 5

What is the amount of solids released into wastewater by human beings?

A)30 gpcd
B)40 gpcd
C)60 gpcd
D)70 gpcd

Question 6

What is the percentage of aerobically digested sludge?

A)0.2-0.5
B)0.3-0.6
C)1.0-2.0
D)1.5-3.0

Question 7

Ws = Wsp + Wss What does Wsp stand for in the above equation?

A)Total dry solids
B)Raw primary solids
C)Suspended solids
D)none

Question 8

Sludge from the primary clarifier is ______

A)Brown and flocculant like appearance
B)Dark in colour
C)Gray and slimy
D)Dark brown in colour

Question 9

How does the chemical sludge appear?

A)Gray in colour and not slimy
B)Brown and flocculant like appearance
C)Red/grayish brown
D)Black in colour

Question 10

How does the activated sludge appear?

A)Gray
B)Red
C)Brown and flocculant like appearance
D)Greasy

Question 11

What is the % of dry solids assumed for a primary sludge from a settling tank at the outlet?

A)12%
B)5-7%
C)8%
D)9-11%

Question 12

What is the percentage of dry solids assumed for the sludge at the outlet of a centrifuge?

A)10-15%
B)1-3%
C)4-8%
D)9-12%