Practice Exam | Questions And Answers With
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1. What is the primary purpose of industrial wastewater treatment?
A. Increase wastewater temperature
B. Remove contaminants before discharge or reuse
C. Add oxygen to groundwater only
D. Increase production costs
Answer: B
Rationale: Industrial wastewater treatment protects public health and the
environment by removing harmful pollutants.
2. Which industrial wastewater characteristic is commonly measured to
determine organic strength?
A. pH
B. BOD
C. Temperature
D. Conductivity only
Answer: B
Rationale: Biochemical Oxygen Demand measures biodegradable organic
pollution strength.
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,3. What does COD measure?
A. Chlorine oxygen demand
B. Chemical oxygen demand
C. Clarifier overflow density
D. Carbon oxidation depth
Answer: B
Rationale: COD measures oxygen required to chemically oxidize
contaminants.
4. Which treatment process removes large solids from industrial
wastewater?
A. Screening
B. Chlorination
C. Aeration
D. Digestion
Answer: A
Rationale: Screening removes large debris before downstream treatment.
5. Which industrial waste characteristic can inhibit biological treatment?
A. Adequate nutrients
B. Toxic compounds
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,C. Proper pH
D. Stable temperature
Answer: B
Rationale: Toxic chemicals may harm or kill treatment microorganisms.
6. Which process adjusts wastewater acidity or alkalinity?
A. Neutralization
B. Sedimentation
C. Filtration
D. Aeration
Answer: A
Rationale: Neutralization balances pH to protect equipment and biological
systems.
7. What is the ideal pH range for most biological treatment systems?
A. 2.0–4.0
B. 6.5–8.5
C. 10.5–12.0
D. 12.5–14.0
Answer: B
Rationale: Most microorganisms function effectively in near-neutral
conditions.
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, 8. Which treatment method removes suspended solids by gravity settling?
A. Clarification
B. Oxidation
C. Chlorination
D. Equalization
Answer: A
Rationale: Clarifiers allow solids to settle from wastewater.
9. What is the purpose of equalization tanks?
A. Increase flow fluctuations
B. Balance flow and pollutant concentrations
C. Eliminate dissolved oxygen
D. Remove all pathogens
Answer: B
Rationale: Equalization stabilizes wastewater flow and strength.
10. Which process uses microorganisms to degrade organic pollutants?
A. Biological treatment
B. Screening
C. Filtration
D. Disinfection
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