Feed water is typically heated with:

Feed water is typically heated with waste or extracted steam because this process efficiently utilizes steam that would otherwise go to waste. In many industrial and heating systems, especially those involving boilers, steam is produced and some of it is usable for heating the feed water. By using waste or extracted steam, the system maximizes energy efficiency and conserves fuel by reclaiming heat from already generated steam.

This approach aligns with energy conservation principles, as it reduces the need for additional energy sources to heat water, thus lowering operational costs and increasing overall system effectiveness. Using waste heat is common in cogeneration systems where steam byproduct is available for other uses.

The other heating methods, while potentially valid, may not be as efficient or widely implemented within standard practices in plant operations. For instance, commercial hot water heaters would require additional energy input, and using another burner would also likely lead to increases in energy consumption and costs. Superheaters are designed to increase the temperature of steam but are not typically used to heat feed water directly. Thus, waste or extracted steam emerges as the most effective and resource-conserving method for this purpose.