1. Your final effluent flow is 5 mgd and you are feeding 100 lbs per day of disinfection, what is the chlorine residual in mg/L?
a. 4.2 mg/L
b. 2.4 mg/L
c. 5.9 mg/L
d. 7.1 mg/L
2. Unit processes used for sludge dewatering include the following except _.
a. Centrifugation
b. Dissolved air floatation
c. Pressure filtration
d. Belt filter presses
3. Odors in the preliminary treatment area come from all of the following except _.
a. Anaerobic digestion gases
b. Screenings
c. Grit
d. Influent wastewater
4. Some pressure filter systems for dewatering use a _ system to help dewater sludges high in oils and grease.
a. Heating
b. Compressed air
c. Vacuum
d. Precoat
5. Sludge cake is moved through a multiple-hearth furnace by a process called _.
a. Rabbling
b. Dosing
c. Pushing
d. Turning
Answers:
1. b
2. b
3. a
4. d
5. a