Q1: Which of the following is the most suitable for removing fine particles (< 1 micron diameter) from air below its dew point ?

ANS:B - Electrostatic precipitator

The most suitable option for removing fine particles (< 1 micron diameter) from air below its dew point is the Electrostatic Precipitator. Explanation:

1. Venturi scrubber: Venturi scrubbers are effective at removing larger particles from air by using a combination of high-velocity air and liquid droplets to capture and remove contaminants. However, they may not be as efficient in capturing fine particles below 1 micron in diameter, especially in air below its dew point.
2. Electrostatic precipitator (ESP): Electrostatic precipitators use electrostatic charges to attract and collect particles from an airflow. They are highly effective at capturing fine particles, including those smaller than 1 micron in diameter. ESPs can operate efficiently even in air below its dew point, making them suitable for a wide range of applications, including industrial emissions control and air purification.
3. Cyclone separator: Cyclone separators are primarily used for removing larger particles from air or gas streams through centrifugal force. While they may capture some finer particles, their efficiency decreases for particles below 1 micron in diameter, especially in air below its dew point.
4. Fabric filter: Fabric filters, also known as baghouses, use woven or felted fabric bags to filter particles from an airflow. They are effective at capturing a wide range of particle sizes, including fine particles. However, their efficiency may decrease in air below its dew point, as moisture can affect the performance of the fabric filter.