Which formula is used to calculate the Btu/lb heat content of fuel oil?

The formula used to calculate the Btu/lb heat content of fuel oil is based on the American Petroleum Institute (API) gravity, which provides a measure of the density of petroleum liquids. The correct formula incorporates the specific coefficients that accurately relate the API gravity to the heat content.

This particular formula, which is expressed as 17,687 + 57.7 x API @ 60 degrees F, indicates that for each degree increase in API gravity, the heat content increases by 57.7 Btu/lb. The constant 17,687 in the formula represents a baseline heat content for fuel oil at a specific density (API gravity) at 60 degrees Fahrenheit.

Utilizing this formula is essential for evaluating energy content in various heating applications, ensuring the efficiency of fuel use and supporting calculations needed for design and operational optimization in systems utilizing fuel oil. Understanding this relationship helps professionals make informed decisions regarding fuel selection and combustion systems.