What is the outlet temperature of the air heater?

The correct answer, which indicates an outlet temperature of 350°C for the air heater, can be understood in the context of typical operating parameters for industrial air heaters. Air heaters are designed to raise the temperature of air used in various processes, including combustion in boilers or gas turbines, by transferring heat from flue gases or other hot substances.

In many heating applications, the outlet temperature needs to be sufficiently high to ensure optimal efficiency. A temperature of 350°C is realistic and often required to achieve effective thermal energy transfer in many industrial systems. This temperature allows the heated air to effectively support combustion processes or to enable preheating of combustion air, thus enhancing fuel efficiency and reducing emissions.

In contrast, other temperatures such as 27°C might be too low for an air heater's intended application, representing more of an ambient or initial temperature rather than an outlet temperature. Similarly, 170°C could be achievable in specific low-temperature applications but would not be typical for systems requiring significant heat input for combustion. Lastly, temperatures like 600°C are generally beyond the design limits for most air heaters to avoid material degradation or failure, making 350°C the optimal choice for practical applications.