How Heat Is Transferred in Industrial Furnaces

Industrial furnaces, also known as industrial process furnaces or direct fired heaters, are furnaces or heaters especially used for processes and operations in metal industries, glass industries, oil industries, and any other fields.

Heat transfer process

Some industrial furnaces make use of electricity in producing and processing heat. These industrial processes are mainly used in steel and other similar industries. Most other industries, however, make use of fuel and fuel systems.

Industrial furnaces that make use of fuel and fuel systems are equipped with burners that burn the fuel with the help of air blown by internal air blowers. In some cases, these burners are arranged into cells, mounted on the furnace floor, on the furnace walls, or on the furnace roof. These burners or cells heat up a set of tubes through the flames produced by the burners. These tubes, in turn, heat the fluid contained in the firebox or radiant section of the industrial furnace.

Combustion takes place in the radiant section of the furnace. Heat is then radiated to the tubes surrounding the fire in the chamber. The heating fluid passes flows through the tubes and combustion gases are released. These gases are referred to as “flue gas”. When this gas leaves the firebox, it usually goes to a convection section for further heat extraction and recovery. After that, flue gas is released into the atmosphere through industrial furnace parts called flue gas stacks.

The important thing to note is that heat in this type of furnace is transferred through radiation, which means that heat travels through the air directly to where it’s supposed to go.