Residual fuel oil

Also known as: resid, No. 6 fuel oil, heavy fuel oil, 6 oil

Residual fuel oil is one of the lowest-value petroleum products from a refinery. It is essentially a by-product of producing the light products that are the primary focus of a refinery.

The primary end use for residual fuel oil is as a fuel in simple furnaces such as power plants and industrial boilers. It is also the primary fuel used on ocean-going ships, where it is called bunker fuel.

Nonetheless, residual fuel oil has some quality specifications that it must meet, for performance and environmental reasons. The most important are:

  • Viscosity - This is a measure of a fluid's tendency to resist flow. Lower viscosity is more desirable
  • Sulfur content - Fuel oil has a maximum sulfur content determined by environmental concerns. This is typically set as a maximum sulfur content in wt %.

Residual fuel oil is the heaviest among a range of different fuel oil grades.

The Refinery Reference Desk includes content derived from our industry experts as well as from public data sources such as company websites. Nothing herein is intended to serve as investment advice. This material is based on information that we believe to be reliable and adequately comprehensive, but we do not represent that such information is in all respects accurate or complete. McKinsey Energy Insights does not accept any liability for any losses resulting from use of the content.



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