MCQ Detailed View

Gravity settling chambers are industrial devices designed to remove suspended particulate matter (SPM) from air, gas, or smoke streams. Industries such as cement plants, steel factories, and power plants often generate dust and particulate emissions. These suspended particles can be harmful to human health and the environment, so removing them before release is essential.

The chamber works on the principle of gravity settling, where heavy particles settle out of the gas stream due to their weight. As the polluted gas enters the chamber, it slows down, allowing the suspended particles to fall to the bottom of the chamber, while the cleaner gas exits from the top. This process is simple, cost-effective, and suitable for large particles (typically greater than 50 micrometers).

Other options in the question are incorrect:

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  NOx (Nitrogen oxides) and SOx (Sulfur oxides) are gaseous pollutants and cannot be removed by gravity settling; they require chemical or catalytic treatment.

  
  


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  CO (Carbon monoxide) is a gas and also cannot be removed by settling chambers.

  
  

Gravity settling chambers are often used as a pre-treatment step before more advanced filtration systems, such as electrostatic precipitators or bag filters, which can remove smaller particles. Understanding their role is essential in industrial hygiene, environmental science, and chemical engineering, as controlling particulate matter reduces air pollution, protects machinery, and ensures compliance with environmental regulations.

In summary, the correct answer is Suspended particulate matter, as gravity settling chambers are specifically designed to allow heavy particles in industrial emissions to settle out, resulting in cleaner air and safer industrial operations.