What action is recommended if there is a fire in the pulverizer?

When addressing a fire in the pulverizer, reducing the air supply is a crucial action. In a combustion process, the ignition of volatile materials requires oxygen, and controlling the air supply can limit the amount of oxygen available to sustain the fire. By cutting back on the air supply, the fuel cannot burn efficiently, which helps to extinguish the flames effectively.

It is important to note that increasing the air supply would promote combustion, making the situation worse, as it would provide more oxygen for the fire. Shutting down the boiler may be an appropriate action in some emergency situations, but it does not directly address the immediate danger of the fire in the pulverizer itself. Discharging water into the pulverizer could also exacerbate the issue by introducing an uncontrolled reaction with the burning materials and potentially spreading the fire.

Therefore, reducing the air supply is the most fitting method to help control and extinguish a fire in the pulverizer.