Question

Which of the following is NOT a correct component of a modern steam power plant?
1. Induced draught mill.
2. Ash precipitators
3. Switch yard
4. Wagon tippler

Answer 1

Correct Answer - Option 1 : Induced draught mill.

Induced draft mill:

• In this system, the blower is located near the base of the chimney instead of near the grate.
• The air is sucked in the system by reducing the pressure through the system below atmosphere.
• The induced draught fan sucks the burned gases from the furnace and the pressure inside the furnace is reduced below atmosphere and induces the atmospheric air to flow through the furnace.
• The action of the induced draught is similar to the action of the chimney.
• The draught produced is independent of the temperature of the hot gases therefore the gases may be discharged as cold as possible after recovering as much heat as possible in air-preheater and economizer.
• Earlier it is part of steam power plants, but in modern steam power plants it is not a part of plant.

 

Ash Precipitators:

• 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 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.

Switchyard:

• A switchyard is a switching station that is the main link between the generating plant and the transmission system.
• It can be considered as the heart of the power plant, the generated power will only be worthy if it can be transmitted and received by the consumers.

 

Wagon tippler:

• The wagon tippling system is designed to unload materials like coal, ore, limestone, etc. from the open-type railway wagons.
• It consists of a wagon tippler, the wagon positioning equipment, underground hopper (RCC type with suitable liner or structural steel fabricated type), and feeder below the hopper for evacuating the material unloaded into the hopper