Question:
The bacteria mainly responsible for crown corrosion in a sewer is ___________.
The bacteria mainly responsible for crown corrosion in a sewer is ___________.
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Crown corrosion in sewers is due to biological activity of sulphur reducing bacteria which produce hydrogen sulphide, leading to sulphuric acid formation.
Updated On: Apr 3, 2025
- Methanogenic bacteria
- Denitrifying bacteria
- Sulphur reducing bacteria
- Pseudomonas bacteria
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The Correct Option is C
Solution and Explanation
Sulphur reducing bacteria (SRB) are anaerobic bacteria that reduce sulphates to hydrogen sulphide gas (H\(_2\)S) in sewage systems.
This hydrogen sulphide, upon reaching the crown of the sewer where oxygen is present, gets oxidized to sulphuric acid.
The sulphuric acid reacts with the concrete and leads to deterioration of the sewer crown, a process known as crown corrosion.
Hence, the correct answer is (C).
This hydrogen sulphide, upon reaching the crown of the sewer where oxygen is present, gets oxidized to sulphuric acid.
The sulphuric acid reacts with the concrete and leads to deterioration of the sewer crown, a process known as crown corrosion.
Hence, the correct answer is (C).
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