What is the function of a feedwater heater?

The function of a feedwater heater is to heat feedwater before it enters the boiler. This process is vital for improving the overall efficiency of the steam generation system. By raising the temperature of the water, the feedwater heater reduces the amount of energy required for the boiler to convert water into steam. This not only minimizes the fuel consumption but also enhances the thermal efficiency of the boiler operation.

In addition, preheating the feedwater helps to reduce thermal shock to the boiler as it minimizes the temperature differential between the incoming feedwater and the water already present in the boiler. This contributes to safer operation and prolongs the lifespan of the boiler components by preventing stress caused by rapid temperature changes.

In contrast, cooling water before it enters the boiler would be counterproductive, as the goal is to make the water suitable for efficient steam production. While some systems may have filtration processes, the primary role of a feedwater heater is specifically to elevate the temperature of the feedwater. Storing excess steam is a function of steam accumulators or other devices, not of the feedwater heater itself.