Question

Pulverized coal is
A. Coal free from ash.
B. Non-smoking coal.
C. Coal which burns for long.
D. Coal broken into fine particles

Answer 1

Hint: In this question, the concept of the type of coal is used to discuss the pulverized coal. First discuss pulverized coal and how it is made from coal then describe how it is used in the furnace.

Complete step by step answer:
As we know that pulverized coal is the type of coal which is broken into fine articles. Usually coal is collected as black coloured sedimentary rock and then it is broken into fine particles which is known as pulverized coal. It is used in furnaces to generate thermal energy from it.
The main advantage of using pulverized coal is that it is made fine enough, it will burn as easily as gas. Hence the pulverized coal is blown in the furnace easily. Pulverized coal is made from coal as the coals are crushed between cylindrical rollers and then it is air heated at about ${340}^{\circ }\text{C}$. After that the pulverized coal is directly blown into the burner as a fuel.
Pulverized coal is mainly used because it is fine enough that its combustion rate is very high. The combustion of pulverized coal occurs mainly at gaseous state because in this state its combustion rate can be controlled easily.
Hence, the correct option is D.

Note: Coal pulverisers are used mainly because it pulverizes the coal into very fine particles so that when it is sent to the boiler it burns very easily. There are different types of pulverising mills which are used to reduce the particle size of the coal such as Ball and tube mill.