What are the main purposes of a deaerator?

A deaerator serves critical functions within a steam system. Its primary role is to preheat the feedwater, enabling it to enter the boiler at a higher temperature. This enhances system efficiency and helps reduce fuel consumption.

Additionally, a key purpose of a deaerator is to remove dissolved gases, particularly oxygen and carbon dioxide, from the feedwater. These gases can lead to corrosion within the boiler and associated piping, potentially causing significant damage over time. By eliminating these gases, the deaerator helps maintain the integrity of the system and extends the lifespan of essential components.

Lastly, the deaerator also provides storage for the feedwater. Having a storage capacity allows for a consistent supply of feedwater to the boiler, facilitating smooth operation and better management of water levels within the system.

These functions collectively contribute to the efficiency, safety, and longevity of a steam boiler system, making option C the correct choice.