Certification Practice Exam Questions And

Textile Industry Waste Treatment Operator Certification Practice Exam Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf Covers wastewater processes, textile chemistry, pollution control, safety, and regulations.)

1. The primary purpose of a textile wastewater treatment plant is to:

a) Produce drinking water

b) Recover dyes for reuse

c) Remove pollutants before discharge

d) Reduce textile production cost

Rationale: Treatment removes chemical, physical, and biological

contaminants to meet discharge standards.

2. The main source of Biological Oxygen Demand (BOD) in textile effluent is:

a) Sodium hydroxide

b) Hydrogen peroxide 1 / 3

c) Sizing and starch materials

d) Sulfuric acid

Rationale: Starch and other organic sizing agents are biodegradable and

increase BOD.

3. High pH in textile wastewater is typically due to:

a) Acid dyes

b) Alkali used in scouring and bleaching

c) Salt addition

d) Sulfide compounds

Rationale: Sodium hydroxide and soda ash raise the pH during scouring

and bleaching.

4. The process that removes suspended solids by gravity is:

a) Sedimentation

b) Filtration

c) Aeration

d) Chlorination

Rationale: Sedimentation tanks allow heavier solids to settle by gravity.

5. Color in textile wastewater mainly comes from:

a) Detergents

b) Enzymes

c) Dyes and pigments

d) Oils and greases

Rationale: Residual dyes are the major cause of visible color in effluent. 2 / 3

• Which treatment step removes oil and grease effectively?

a) Aeration

b) Neutralization

c) Dissolved Air Flotation (DAF)

d) Coagulation

Rationale: DAF separates light, hydrophobic materials like oil and grease

using air bubbles.

7. COD stands for:

a) Carbon Oxygen Demand

b) Chemical Oxygen Demand

c) Combined Oxygen Demand

d) Compound Oxidation Degree

Rationale: COD measures total oxidizable compounds, both biodegradable

and non-biodegradable.

• The main parameter used to measure acidity or alkalinity of wastewater

is:

• pH

b) Conductivity

c) Alkalinity

d) Turbidity

Rationale: pH quantifies hydrogen ion concentration indicating acidity or

basicity.

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