Subject : Power Plant Engineering

Topic: Chap 3: Steam Power Plants

Difficulty: Medium

Marks : 5M

This includes coal delivery, preparation, coal handling, boiler furnace, ash handling and ash storage. The coal from coal mines is delivered by ships, rail or by trucks to the power station. This coal is sized by crushers, breakers etc. The sized coal is then stored in coal storage (stock yard).

From the stock yard, the coal is transferred to the boiler furnace by means of conveyors, elevators etc. The coal is burnt in the boiler furnace and ash is formed by burning of coal, Ash coming out of the furnace will be too hot, dusty and accompanied by some poisonous gases.

The ash is transferred to ash storage. Usually, the ash is quenched to reduced temperature corrosion and dust content. There are different methods employed for the disposal of ash.

They are hydraulic system, water jetting, ash sluice ways, pneumatic system etc. In large power plants hydraulic system is used. In this system, ash falls from furnace grate into high velocity water stream. It is then carried to the slumps.