What is a key disadvantage of a separately fired superheater?

The key disadvantage of a separately fired superheater is indeed the higher first cost associated with its installation and operation. A separately fired superheater requires an additional burner and control system to provide the necessary heat to superheat the steam, which increases both the initial capital investment and the complexity of the system.

This additional equipment includes separate combustion systems, fuel handling, and automation controls, contributing to the overall cost. The complexity also often results in higher maintenance requirements and potential for operational challenges. In contrast, integral superheaters are built directly into the boiler and benefit from a more streamlined design, which is generally less expensive upfront.

Although other options might present concerns in different contexts, such as steam temperature or efficiency, they do not encompass the primary financial burden associated with adopting a separately fired superheater system. The focus here is primarily on the initial expenses required to implement this additional layer of heating capability.