What component uses heat from the boiler exhaust gases to preheat the feedwater?

What component uses heat from the boiler exhaust gases to preheat the feedwater?

• A. Economizer
• B. Steam drum
• C. Heat exchanger
• D. Air preheater

Answer: (A)

The component that uses heat from the boiler exhaust gases to preheat the feedwater is the economizer. Economizers are designed to capture waste heat from the flue gases that are expelled after combustion in the boiler. By doing so, they improve the overall efficiency of the boiler system. When the economizer heats the feedwater before it enters the boiler, it reduces the amount of fuel required to bring that water up to the desired temperature for steam generation. This process enhances system efficiency by recovering energy that would otherwise be lost, thereby lowering operational costs and reducing emissions. In contrast, while the steam drum is a critical part of the boiler where steam and water interaction takes place, it does not serve the function of preheating feedwater with exhaust heat. Heat exchangers can perform various heat transfer functions, but the specific application of recovering waste heat from flue gases to preheat feedwater is specifically the role of an economizer. An air preheater is designed to heat incoming air for combustion, rather than preheating feedwater. Thus, the economizer is the correct component for this function.

The component that uses heat from the boiler exhaust gases to preheat the feedwater is the economizer. Economizers are designed to capture waste heat from the flue gases that are expelled after combustion in the boiler. By doing so, they improve the overall efficiency of the boiler system.

When the economizer heats the feedwater before it enters the boiler, it reduces the amount of fuel required to bring that water up to the desired temperature for steam generation. This process enhances system efficiency by recovering energy that would otherwise be lost, thereby lowering operational costs and reducing emissions.

In contrast, while the steam drum is a critical part of the boiler where steam and water interaction takes place, it does not serve the function of preheating feedwater with exhaust heat. Heat exchangers can perform various heat transfer functions, but the specific application of recovering waste heat from flue gases to preheat feedwater is specifically the role of an economizer. An air preheater is designed to heat incoming air for combustion, rather than preheating feedwater. Thus, the economizer is the correct component for this function.