Question

Arrange the following devices in increasing order of particulate collection efficiency for fine particles: \[ \begin{aligned} A.&\ \text{Gravity settling chamber}\\ B.&\ \text{Cyclone separator}\\ C.&\ \text{Electrostatic precipitator} \end{aligned} \]

• A. \(A\lt C\lt B\)
• B. \(A\lt B\lt C\)
• C. \(B\lt A\lt C\)
• D. \(A\gt B\gt C\)

Hint:

Increasing collection efficiency: \[ \boxed{ \text{Gravity Chamber} \lt \text{Cyclone} \lt \text{ESP} \lt \text{Fabric Filter} } \]

Answer 1

The Correct Option is B

Step 1: Rank each device by its working principle.
Gravity settling chambers only let heavy, coarse particles fall out under gravity, so they catch the least.
Step 2: Place the cyclone separator next.
Cyclone separators use centrifugal force, which handles smaller particles better than plain gravity settling but still struggles with very fine dust.
Step 3: Put the electrostatic precipitator at the top.
ESPs use electric charge and field forces, which remain effective even for fine and sub-micron particles, giving them the best efficiency of the three.
Step 4: Write the final order.
Increasing efficiency runs from gravity settling chamber, to cyclone separator, to electrostatic precipitator, that is, A less than B less than C.
\[ \boxed{A \lt B \lt C} \]