Question

At this stage of wastewater treatment, methanogenic microbes are the most significant

(a) Sludge digestion

(b) Primary treatment

(c) Secondary treatment

(d) Biological oxidation
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Answer 1

At the (a) Sludge digestion stage of wastewater treatment, methanogenic microbes are the most significant.

• Sewage treatment is a process that aims at removing pollutants from wastewater.
• The various steps include Physical Treatment, Biological Treatment, Sludge digestion (Anaerobic Treatment), and Chemical Treatment.
• After the organic matter is digested by the aerobic bacteria in the biological treatment, the water is sent to anaerobic sludge digesters for treatment.
• In sludge digestion, the flocs of aerobic bacteria and fungi are digested by anaerobic bacteria like Methanogens.

Answer 2

Wastewater treatment or Sewage treatment is a process of removing substrates, harmful microbes, etc and chemically treating it to provide water which can be recycled.

Explanation:

Wastewater treatment or Sewage treatment is a process of removing substrates, harmful microbes, etc and chemically treating it to provide water which can be recycled.

Wastewater treatment can be classified into 4 stages:

1. Primary Treatment
2. Secondary Treatment
3. Tertiary Treatment
4. Biological oxidation

• Sludge digestion is the process where remnants are treated.
• It is a biological process where the organic matter is decomposed into stable form. This often happens during secondary treatment.
• Treatment  happens through anaerobic respiration during which the methanogens break down the organic matter to produce carbon dioxide, methane, nitrogen and other substances.
• Methanogens are found in abundance in the process of sludge digestion where they actively reduce the organic matter into simpler forms and release gases.

Sludge digestion is the stage of wastewater treatment where Methanogens are present in abundance.