Biological Processes for Industrial and Domestic Effluents

What is the main purpose of biological wastewater treatment?

To remove contaminants after primary treatment (correct)
To increase pollution incidents
To discharge untreated wastewater
To generate more wastewater

Which of the following is NOT mentioned as a source of wastewater in the text?

Industrial activities
Commercial activities (correct)
Agricultural activities
Military activities

What types of microorganisms are used in biological wastewater treatment?

Insects, mammals, reptiles
Bacteria, nematodes, algae (correct)
Protozoa, rotifers, fungi
Viruses, arthropods, annelids

Why is accidental spillage mentioned as a concern in the text?

To demonstrate potential consequences of pollutants getting into the environment (B) Signup and view all the answers

What does biological treatment help transform dissolved materials into?

Stable inorganic forms (D) Signup and view all the answers

How are biological treatments classified based on the text?

Based on process (A) Signup and view all the answers

What is the main difference between biological aerobic treatment and biological anaerobic treatment?

Presence of oxygen in aerobic treatment and absence of oxygen in anaerobic treatment (C) Signup and view all the answers

Which type of treatment yields a cleaner water effluent, resulting in high-quality effluent production?

Biological aerobic treatment (B) Signup and view all the answers

What is the key feature of the activated sludge process mentioned in the text?

Highly concentrated microorganisms to degrade organics (C) Signup and view all the answers

Why is biological aerobic treatment considered a rapid and efficient waste treatment process?

Due to the presence of oxygen (A) Signup and view all the answers

Which microorganisms are primarily responsible for utilizing organic matter in biological wastewater treatment?

Bacteria, algae, and fungi (D) Signup and view all the answers

What is the reason behind the activated sludge process being widely used in the secondary stage of wastewater treatment?

Efficient degradation of organics and nutrient removal (D) Signup and view all the answers

What is the main purpose of aeration in the activated sludge process?

To promote the growth of microorganisms that degrade organic matter (D) Signup and view all the answers

What is the purpose of the settling tank in the activated sludge process?

To separate the microbial mass (sludge) from the treated wastewater (D) Signup and view all the answers

What is the purpose of trickling filters in wastewater treatment?

To remove compounds like ammonia from the wastewater after primary treatment (C) Signup and view all the answers

What is the function of the biological film or slime layer in trickling filters?

To provide a surface for microorganisms to attach and degrade organic material (B) Signup and view all the answers

What is the purpose of aeration in aerated lagoons?

To introduce oxygen into the lagoon to promote biological oxidation of the wastewater (B) Signup and view all the answers

Which of the following is NOT a type of aerobic wastewater treatment method discussed in the text?

Anaerobic digestion (D) Signup and view all the answers

What is the primary purpose of oxidation ponds?

To facilitate the interaction between sunlight, bacteria, algae and other organisms to break down organic matter (B) Signup and view all the answers

What is a disadvantage of oxidation ponds?

They require a large area of land (A) Signup and view all the answers

Which statement is true about biological anaerobic treatment?

It is used to treat high-strength wastewater before discharge to a municipal sewer system (C) Signup and view all the answers

What is a characteristic of anaerobic digestion?

It is used for sludge degradation and stabilization in wastewater treatment plants (D) Signup and view all the answers

What is a benefit of anaerobic treatment?

It is able to stabilize the water with little biomass production (A) Signup and view all the answers

Which statement is true about the effluent from aerated ponds?

It may be reused or used for recharge (C) Signup and view all the answers

What is the role of methanogenic archaea populations in anaerobic wastewater treatments?

Enforce anaerobic conditions (D) Signup and view all the answers

How deep should an anaerobic lagoon typically be for more efficiency?

Deeper than 2.5 m (D) Signup and view all the answers

What distinguishes anaerobic lagoons from aerobic lagoons?

Presence of dissolved oxygen (B) Signup and view all the answers

What fills an anaerobic filter for wastewater treatment?

Plastic media (D) Signup and view all the answers

In which direction does the flow occur in an anaerobic filter filled with rocks?

Upward (D) Signup and view all the answers

Why are deeper anaerobic lagoons considered more efficient in wastewater treatment?

To allow anaerobic conditions to prevail (C) Signup and view all the answers