What does an air heater do with waste heat from flue gases?

An air heater functions by utilizing waste heat from flue gases to warm up the combustion air that is introduced into the boiler. By pre-heating the combustion air, it enhances the efficiency of the combustion process inside the boiler. The higher temperature of the air entering the combustion chamber helps to improve fuel combustion efficiency, resulting in better energy utilization and lower emissions.

The purpose of this process is to recover energy that would otherwise be lost with the exhaust gases, thereby improving overall system performance. This not only conserves energy but also supports regulatory compliance by reducing the emission of pollutants associated with combustion.

In contrast, while heating water in the boiler and pre-heating fuel may seem beneficial, air heaters specifically focus on increasing the temperature of combustion air. Dispersing excess heat does not align with the primary function of an air heater, as it instead aims to improve the energy recovery and efficiency of the heating system.