Name: Score:
80 Multiple choice questions
Term 1 of 80
Which is true about chlorine gas?
It is 2.5 times lighter than air
it is 2.5 times heavier than air
It is 1.5 times heavier than air
It is 1.5 times lighter than air
Term 2 of 80
What is a "dead spot" in an activated sludge process?
An area in the secondary clarifier with rising sludge
An area in the aeration tank that has insufficient mixing
An area in the aeration tank that has high concentration of DO
An area in the secondary clarifier with may dead viruses
Term 3 of 80
What is the most common type of grit collector?
Deflectors
Weirs
Chain driven scrapers called "flights"
Parshall flume
,Term 4 of 80
What is sludge bulking in an activated sludge process?
When mixed liquor solids settle slowly and compact to a limited extent
When old sludge denitrify and cause sludge to rise as a result of gastrification
When sludge form large aggregates and cause sludge to settle quickly
When compaction in the secondary clarifier is improved due to chemical injection
Term 5 of 80
What is true if the F/M ratio increases?
Less DO is required
Less BOD is available
DO will not be affected by an increase in F/M ratio
More DO is needed
Term 6 of 80
Why is mixing important in an anaerobic digester?
Increases the build up of grit
Speeds up digestion rate
Achieves heterogeneous content in the digester
Forms a scum blanket
, Term 7 of 80
Where is the proper sampling location for an effluent from a wastewater treatment plant?
Next to the chlorinator equipment
At the end of a solids handling facility
Prior to discharge into receiving waters
At the head of a chlorine contact chamber
Term 8 of 80
Who must be included in a hearing conservation program to prevent hearing loss?
Employees whose normal noise exposure equals or exceeds 65 decibels
Employees whose normal noise exposure equals or exceeds an 8 hour time weighted
average of 85 decibels
Employees whose normal noise exposure exceeds 45 decibels at any time
Employees whose normal noise exposure exceeds and 8 hour time weighted average of 25
decibels
Term 9 of 80
What is used to control filamentous organisms?
Polymer
Sulfur Dioxide
Coagulant
Chlorine
80 Multiple choice questions
Term 1 of 80
Which is true about chlorine gas?
It is 2.5 times lighter than air
it is 2.5 times heavier than air
It is 1.5 times heavier than air
It is 1.5 times lighter than air
Term 2 of 80
What is a "dead spot" in an activated sludge process?
An area in the secondary clarifier with rising sludge
An area in the aeration tank that has insufficient mixing
An area in the aeration tank that has high concentration of DO
An area in the secondary clarifier with may dead viruses
Term 3 of 80
What is the most common type of grit collector?
Deflectors
Weirs
Chain driven scrapers called "flights"
Parshall flume
,Term 4 of 80
What is sludge bulking in an activated sludge process?
When mixed liquor solids settle slowly and compact to a limited extent
When old sludge denitrify and cause sludge to rise as a result of gastrification
When sludge form large aggregates and cause sludge to settle quickly
When compaction in the secondary clarifier is improved due to chemical injection
Term 5 of 80
What is true if the F/M ratio increases?
Less DO is required
Less BOD is available
DO will not be affected by an increase in F/M ratio
More DO is needed
Term 6 of 80
Why is mixing important in an anaerobic digester?
Increases the build up of grit
Speeds up digestion rate
Achieves heterogeneous content in the digester
Forms a scum blanket
, Term 7 of 80
Where is the proper sampling location for an effluent from a wastewater treatment plant?
Next to the chlorinator equipment
At the end of a solids handling facility
Prior to discharge into receiving waters
At the head of a chlorine contact chamber
Term 8 of 80
Who must be included in a hearing conservation program to prevent hearing loss?
Employees whose normal noise exposure equals or exceeds 65 decibels
Employees whose normal noise exposure equals or exceeds an 8 hour time weighted
average of 85 decibels
Employees whose normal noise exposure exceeds 45 decibels at any time
Employees whose normal noise exposure exceeds and 8 hour time weighted average of 25
decibels
Term 9 of 80
What is used to control filamentous organisms?
Polymer
Sulfur Dioxide
Coagulant
Chlorine
