With reference to the "Aeration" process in wastewater treatment, consider the following statements: 1. It involves bubbling air through the wastewater. 2. It is a mechanical process designed to filter out fine dust particles. 3. It creates conditions that inhibit the growth of aerobic bacteria. Which of the statements given above is/are correct?

The correct option is (a). Explanation Aeration is a fundamental process in the secondary (biological) stage of wastewater treatment. It facilitates the transfer of oxygen from the air into the water to support biological activity. - Statement 1 is Correct: The process involves bubbling air or mechanically agitating the water to introduce oxygen. This ensures that the wastewater is sufficiently oxygenated to support the metabolic activities of microorganisms. - Statement 2 is Incorrect: Aeration is not a filtration process for fine dust. Physical removal of solids, such as grit, sand, and large particles, occurs during preliminary and primary treatment stages (e.g., screening and sedimentation). Aeration targets dissolved organic matter rather than particulate dust. - Statement 3 is Incorrect: The specific purpose of aeration is to promote the growth of aerobic bacteria, not inhibit them. These bacteria require oxygen to decompose organic contaminants (such as human waste and food scraps) into stable by-products like carbon dioxide and water. Key Takeaway: Aeration is employed in secondary wastewater treatment to supply oxygen, enabling aerobic bacteria to biodegrade organic pollutants.

With reference to the "Aeration"… - NCERT Class 7 Environment & Ecology MCQ

NCERT Class 7 Environment & Ecology — Chapter 2: Wastewater story

mcqmedium

With reference to the "Aeration" process in wastewater treatment, consider the following statements:

It involves bubbling air through the wastewater.
It is a mechanical process designed to filter out fine dust particles.
It creates conditions that inhibit the growth of aerobic bacteria.

Which of the statements given above is/are correct?

NCERT textbook question

From NCERT Science - class 7 · Page 160

Options

A1 only
B2 only
C1 and 3 only
D1, 2 and 3

Did you get this right?

Solution

The correct option is (a).

Explanation

Aeration is a fundamental process in the secondary (biological) stage of wastewater treatment. It facilitates the transfer of oxygen from the air into the water to support biological activity.

Statement 1 is Correct: The process involves bubbling air or mechanically agitating the water to introduce oxygen. This ensures that the wastewater is sufficiently oxygenated to support the metabolic activities of microorganisms.
Statement 2 is Incorrect: Aeration is not a filtration process for fine dust. Physical removal of solids, such as grit, sand, and large particles, occurs during preliminary and primary treatment stages (e.g., screening and sedimentation). Aeration targets dissolved organic matter rather than particulate dust.
Statement 3 is Incorrect: The specific purpose of aeration is to promote the growth of aerobic bacteria, not inhibit them. These bacteria require oxygen to decompose organic contaminants (such as human waste and food scraps) into stable by-products like carbon dioxide and water.

Key Takeaway: Aeration is employed in secondary wastewater treatment to supply oxygen, enabling aerobic bacteria to biodegrade organic pollutants.

Your note

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