Calorific Value of Fuel

Definition: The calorific value of fuel refers to the heat released when 1kg of fuel (gas fuel is 1m3) is completely burned, and the unit is kJ/kg (or kJ/Nm3). The calorific value of fuel is divided into high calorific value and low calorific value.

High calorific value:

All the heat released when the fuel is completely burned. It contains the latent heat of vaporization of the water vapor generated when the fuel is burned, that is, it is considered that the water vapor in the flue gas is completely condensed into water and releases the latent heat of vaporization. However, when the boiler is actually running, the flue gas still has a temperature of 160-200°C when it leaves the boiler, and the water vapor in the flue gas cannot condense into water and release the latent heat of vaporization. Therefore, the heat that the boiler can actually utilize does not include the latent heat of vaporization of water vapor.

Low calorific value:

The calorific value after deducting the latent heat of vaporization from the high calorific value. In practical engineering it often uses the received base low heat.