Industrial furnace oil (ifo), also known as heavy furnace oil (hfo), is a type of residual oil derived from the distillation of crude oil. It is a highly viscous, dark-colored fuel typically used in industrial heating applications, particularly in large furnaces, boilers, and thermal power plants. Known for its high calorific value and energy output, furnace oil is commonly used in sectors such as cement manufacturing, steel production, and other heavy industries where large amounts of heat are required. Key Features: High Viscosity: Furnace oil is viscous and typically requires preheating before use to reduce its thickness and improve combustion efficiency. High Calorific Value: Provides significant energy output, making it an effective fuel for high-heat applications. Residual Product: It is a byproduct of the crude oil refining process, specifically from the vacuum distillation or atmospheric distillation of heavier crude fractions. Cost-Effective: IFO is relatively inexpensive compared to lighter distillate fuels, making it an economical choice for industries requiring large amounts of fuel for heating.