Correct Answer - Option 3 : 55°
Concept:
- The exhaust gases leaving the boiler contain particles of solid matter in suspension smoke, fly ash, dust soot, and smoke.
- Fuel dust is greater with pulverized fuel.
- Removal of dust from the exhaust gases is very important. Basically, gas cleaning devices called dust collectors.
Dust collectors:
- Dust collectors are classified into mechanical and electrical ones.
- Electrical ones include electrostatic precipitators hoppers.
Electrostatic Precipitator Hoppers:
- Electrostatic precipitator hopper has the advantage of higher efficiency, low-pressure drop, easy removal of collected particles, and capacity of handling a large volume of flue gases.
- The minimum valley angle of an ash hopper used in a dry electrostatic precipitator is generally 55°
