WorksheetsWastewater Engineering Part 4
Total questions: 20
Worksheet time: 2hrs 56mins
The lighter organic material that rises to the surface of the water inside the septic tank
sludge
suspended solids
total suspended solids
scum
organic gases
Determine the length of a septic tank serving 200 persons in a commercial establishment. Assuming depth of 1.50 m, 1.20 meter width of tank per 100 persons, and a wastewater generation of 0.057 cubic meter
3.20 m
2.40 m
3.0 m
4.80 m
3.90 m
The following are gases produced inside the septic tank except
CH4
CO2
HO2
H2
None of the above
Decomposition caused by anaerobic bacteria is sometimes called as _____, is accompanied by bad odor
putrefaction
decomposition
oxidation
sedimentation
none of the above
A sewage that turns dark and smell unpleasantly due to anaerobic decomposition is called _____
gray water
black water
yellow water
septage
septic
Bacteria which still functions even with or without free oxygen
aerobic
anaerobic
facultative
septic
none of the above
Concrete sealed vault with a wooden shelter constructed for the collection of raw sewage
septic tank
privy
cesspool
public sewer
none of the above
Refers to the right choice of the right kind of fittings for a particular change of directions, turns , or offsets
Law of conservation of materials
Conservative use of fittings
Law of conservation of fittings
Law of Energy Conservation
none of the above
The ideal position of horizontal waste pipe , were those installed at ____ slope
1%
1.5%
1.75%
2.0%
2.25%
Determine the fixture unit load of a horizontal pipe to serve 5 urinals , 3 lavatories, 8 showers , and 2 slop sink. Assume units per fixture : (urinals=5; lavatories=1; shower=2;slop sink = 3)
20
30
40
50
60
As per the Plumbing Code , "no water closet shall discharge into a drain less than ___ mm diameter pipe
75 mm
100 mm
150 mm
160 mm
none of the above
Method of treatment in which the application of physical forces predominate
unit operation
unit process
advanced process
preliminary treatment
primary treatment
Flocculation, Aeration, and disinfection are examples of
unit processes
unit operations
advanced treatment
primary treatment
none of the above
In a wastewater facility laboratory, a sample was taken for analysis. As a result, the specific weight of wastewater measured 11.97 kN/m3. Thus, its specific gravity is _____
1.07
1.97
1.197
1.22
none of the above
Develop a sustained BOD peak mass loading curve for a treatment plant with a design flowrate of 1 m3/s. Assume daily BOD concentration is 200 g/m3. What is the mass loading value for BOD, kg/d?
5000 kg/d
200 kg/d
2000 kg/d
17280 kg/d
none of the above
Calculate the F/M given the following:
Influent flow rate = 10 mgd
Primary effluent COD = 200 mg/l
MLVSS = 1550 mg/l
# of aeration tanks in parallel = 4
Aeration tank dimensions:
Depth of water = 20 ft
Length = 120 ft
Width = 24ft
0.52
0.75
1.03
1.4
none of the above
Calculate the SVI for an activated sludge sample given the following: 30-minute settleable solids volume = 150 mL, MLSS = 3,000 mg/L
50 ml/g
100 ml/g
0.5 ml/g
20 ml/g
none of the above
The usual duration in conducting SVI
15 min
30 min
45 min
60 min
none of the above
Given:
Cohesion constant = 0.05
Specific gravity = 1.25
Diameter of Particles = 100 um
Friction factor = 0.025
What is the scour velocity?
0.051 m/s
0.033 m/s
0.063 m/s
0.086 m/s
none of the above
The incoming flowrate of partially treated wastewater in the clarifier is 150 m3/s. What is the overflow rate if the diameter of the tank is 10 m.
1.91 m3/s/m2
1.62 m3/s/m2
2.13 m3/s/m2
3.66 m3/2/m2
none of the above
