Wastewater Questions and Answers |
Latest Version | 2025/2026 | Correct &
Verified
What is the main concern of chlorine residual in effluent?
✔✔It can be toxic to aquatic life if not controlled.
What is the function of effluent polishing ponds?
✔✔To improve the quality of final effluent before discharge.
What is the main purpose of odor control in wastewater plants?
✔✔To protect surrounding communities from nuisance smells.
Why is dissolved oxygen important in wastewater treatment?
✔✔It supports the survival and activity of aerobic microorganisms.
What is sludge digestion?
✔✔A process that stabilizes organic matter and produces biogas.
1
,What does alkalinity help to control in wastewater treatment?
✔✔It buffers pH changes and supports biological processes.
What is the purpose of secondary treatment?
✔✔To biologically reduce BOD and suspended solids in wastewater.
What is the purpose of final disinfection?
✔✔To kill remaining harmful microorganisms before release to the environment.
What gas is produced in large quantities during anaerobic digestion?
✔✔Methane.
What is the purpose of sludge thickening?
✔✔To reduce the water content of sludge before further treatment.
Which organisms are primarily responsible for breaking down organic matter in activated
sludge?
✔✔Aerobic bacteria.
2
,What is the function of secondary clarifiers?
✔✔To separate biological solids from treated wastewater.
What is the common indicator organism used to check for wastewater disinfection efficiency?
✔✔E. coli.
Why is chlorination used in wastewater treatment?
✔✔To destroy harmful microorganisms before discharge.
What does FOG stand for in wastewater management?
✔✔Fats, Oils, and Grease.
What is the main purpose of a trickling filter?
✔✔To provide biological treatment using microorganisms attached to media.
What does an anaerobic condition mean in wastewater treatment?
✔✔It means the absence of oxygen.
3
, Why is pH monitoring important in wastewater treatment?
✔✔To ensure microorganisms can survive and treatment processes work effectively.
What is sludge dewatering designed to achieve?
✔✔It reduces sludge volume by removing water.
What is the role of return activated sludge (RAS)?
✔✔To maintain a sufficient population of microorganisms in the aeration tank.
What is the typical pH range of raw wastewater?
✔✔Between 6.5 and 8.5.
What happens if wastewater is discharged without treatment?
✔✔It can cause water pollution and spread diseases.
What is the purpose of a bar screen?
✔✔To remove large debris like rags, sticks, and plastics from influent.
4
Latest Version | 2025/2026 | Correct &
Verified
What is the main concern of chlorine residual in effluent?
✔✔It can be toxic to aquatic life if not controlled.
What is the function of effluent polishing ponds?
✔✔To improve the quality of final effluent before discharge.
What is the main purpose of odor control in wastewater plants?
✔✔To protect surrounding communities from nuisance smells.
Why is dissolved oxygen important in wastewater treatment?
✔✔It supports the survival and activity of aerobic microorganisms.
What is sludge digestion?
✔✔A process that stabilizes organic matter and produces biogas.
1
,What does alkalinity help to control in wastewater treatment?
✔✔It buffers pH changes and supports biological processes.
What is the purpose of secondary treatment?
✔✔To biologically reduce BOD and suspended solids in wastewater.
What is the purpose of final disinfection?
✔✔To kill remaining harmful microorganisms before release to the environment.
What gas is produced in large quantities during anaerobic digestion?
✔✔Methane.
What is the purpose of sludge thickening?
✔✔To reduce the water content of sludge before further treatment.
Which organisms are primarily responsible for breaking down organic matter in activated
sludge?
✔✔Aerobic bacteria.
2
,What is the function of secondary clarifiers?
✔✔To separate biological solids from treated wastewater.
What is the common indicator organism used to check for wastewater disinfection efficiency?
✔✔E. coli.
Why is chlorination used in wastewater treatment?
✔✔To destroy harmful microorganisms before discharge.
What does FOG stand for in wastewater management?
✔✔Fats, Oils, and Grease.
What is the main purpose of a trickling filter?
✔✔To provide biological treatment using microorganisms attached to media.
What does an anaerobic condition mean in wastewater treatment?
✔✔It means the absence of oxygen.
3
, Why is pH monitoring important in wastewater treatment?
✔✔To ensure microorganisms can survive and treatment processes work effectively.
What is sludge dewatering designed to achieve?
✔✔It reduces sludge volume by removing water.
What is the role of return activated sludge (RAS)?
✔✔To maintain a sufficient population of microorganisms in the aeration tank.
What is the typical pH range of raw wastewater?
✔✔Between 6.5 and 8.5.
What happens if wastewater is discharged without treatment?
✔✔It can cause water pollution and spread diseases.
What is the purpose of a bar screen?
✔✔To remove large debris like rags, sticks, and plastics from influent.
4
