What is the most common reason d) Storm events
wastewater would contain intermittent
amounts of detritus?_______ :
a) Industrial discharges
b) Commercial discharges
c) Residential discharges
d) Storm events
Combined systems contain wastewater c) Sanitary wastewater and surface runoff
from both:
a) Domestic and commercial
wastewater
b) Sanitary wastewater
c) Sanitary wastewater and surface
runoff
d) Surface runoff
In general, wastewater is what d) 0.1%
percentage solids content?
a) 1.0%
b) 0.7%
c) 0.5%
d) 0.1%
,In general, wastewater is what b) 30%
percentage suspended solids content?
a) 25%
b) 30%
c) 35%
d) 40%
Aerobic bacteria will only reproduce in d) Free or dissolved oxygen
an environment with only:
a) Free or dissolved nitrates
b) Free or dissolved phosphates
c) Free or dissolved carbon dioxide
d) Free or dissolved oxygen
Anaerobic bacteria will only reproduce d) Free or dissolved oxygen
in an environment that lacks:
a) Free or dissolved nitrates
b) Free or dissolved phosphates
c) Free or dissolved carbon dioxide
d) Free or dissolved oxygen
, c) 5 days
Biochemical oxygen demand (BOD) "The biochemical oxygen demand (BOD5) determines the amount of
test incubates for a time of: biodegradable organic material in wastewater by measuring the oxygen
a) 24 hours consumed by micro-organisms in decomposing the waste. The test is don
b) 2 days measuring the dissolved oxygen concentration of a sample before and af
c) 5 days incubation under standard conditions (usually in the dark, for 5 days at 20o
d) 7 days The BOD5 standard sample bottles are 300mL volume and the samples ca
preserved in a refrigerator at 4oC for up to a maximum holding time of 2 d
a) 20 oC
Biochemical oxygen demand (BOD)
"The biochemical oxygen demand (BOD5) determines the amount of
test incubates at a temperature of:
biodegradable organic material in wastewater by measuring the oxygen
startup.
consumed by micro-organisms in decomposing the waste. The test is don
a) 20 oC
measuring the dissolved oxygen concentration of a sample before and af
b) 21 oC
incubation under standard conditions (usually in the dark, for 5 days at 20o
c) 25 oC
The BOD5 standard sample bottles are 300mL volume and the samples ca
d) 30 oC
preserved in a refrigerator at 4oC for up to a maximum holding time of 2 d
An Imhoff cone measures: b) Volume of settleable solids
a) Clarity of the wastewater
b) Volume of settleable solids
c) Depth of sludge in a clarifier
d) Floc carry over to next process
, The major gas produced in digesters is: c) Methane
a) Hydrogen
b) Hydrogen sulphide
c) Methane
d) Carbon dioxide
What is the angle of the bars on a b) 30 o
manually cleaned bar screen?
a) 25 o
b) 30 o
c) 35 o
d) 40 o
What is the angle of the bars on a c) 45 to 60 o
mechanically cleaned bar screen?
a) 30 to 45 o
b) 35 to 50 o
c) 45 to 60 o
d) 50 to 65 o
wastewater would contain intermittent
amounts of detritus?_______ :
a) Industrial discharges
b) Commercial discharges
c) Residential discharges
d) Storm events
Combined systems contain wastewater c) Sanitary wastewater and surface runoff
from both:
a) Domestic and commercial
wastewater
b) Sanitary wastewater
c) Sanitary wastewater and surface
runoff
d) Surface runoff
In general, wastewater is what d) 0.1%
percentage solids content?
a) 1.0%
b) 0.7%
c) 0.5%
d) 0.1%
,In general, wastewater is what b) 30%
percentage suspended solids content?
a) 25%
b) 30%
c) 35%
d) 40%
Aerobic bacteria will only reproduce in d) Free or dissolved oxygen
an environment with only:
a) Free or dissolved nitrates
b) Free or dissolved phosphates
c) Free or dissolved carbon dioxide
d) Free or dissolved oxygen
Anaerobic bacteria will only reproduce d) Free or dissolved oxygen
in an environment that lacks:
a) Free or dissolved nitrates
b) Free or dissolved phosphates
c) Free or dissolved carbon dioxide
d) Free or dissolved oxygen
, c) 5 days
Biochemical oxygen demand (BOD) "The biochemical oxygen demand (BOD5) determines the amount of
test incubates for a time of: biodegradable organic material in wastewater by measuring the oxygen
a) 24 hours consumed by micro-organisms in decomposing the waste. The test is don
b) 2 days measuring the dissolved oxygen concentration of a sample before and af
c) 5 days incubation under standard conditions (usually in the dark, for 5 days at 20o
d) 7 days The BOD5 standard sample bottles are 300mL volume and the samples ca
preserved in a refrigerator at 4oC for up to a maximum holding time of 2 d
a) 20 oC
Biochemical oxygen demand (BOD)
"The biochemical oxygen demand (BOD5) determines the amount of
test incubates at a temperature of:
biodegradable organic material in wastewater by measuring the oxygen
startup.
consumed by micro-organisms in decomposing the waste. The test is don
a) 20 oC
measuring the dissolved oxygen concentration of a sample before and af
b) 21 oC
incubation under standard conditions (usually in the dark, for 5 days at 20o
c) 25 oC
The BOD5 standard sample bottles are 300mL volume and the samples ca
d) 30 oC
preserved in a refrigerator at 4oC for up to a maximum holding time of 2 d
An Imhoff cone measures: b) Volume of settleable solids
a) Clarity of the wastewater
b) Volume of settleable solids
c) Depth of sludge in a clarifier
d) Floc carry over to next process
, The major gas produced in digesters is: c) Methane
a) Hydrogen
b) Hydrogen sulphide
c) Methane
d) Carbon dioxide
What is the angle of the bars on a b) 30 o
manually cleaned bar screen?
a) 25 o
b) 30 o
c) 35 o
d) 40 o
What is the angle of the bars on a c) 45 to 60 o
mechanically cleaned bar screen?
a) 30 to 45 o
b) 35 to 50 o
c) 45 to 60 o
d) 50 to 65 o
