Concept

Heavy fuel oil

Summary
Heavy fuel oil (HFO) is a category of fuel oils of a tar-like consistency. Also known as bunker fuel, or residual fuel oil, HFO is the result or remnant from the distillation and cracking process of petroleum. For this reason, HFO is contaminated with several different compounds including aromatics, sulfur and nitrogen, making emissions upon combustion more polluting compared to other fuel oils. HFO is predominantly used as a fuel source for marine vessel propulsion using marine diesel engines due to its relatively low cost compared to cleaner fuel sources such as distillates. The use and carriage of HFO on-board vessels presents several environmental concerns, namely the risk of oil spill and the emission of toxic compounds and particulates including black carbon. Presently, the use of HFOs is banned as a fuel source for ships travelling in the Antarctic as part of the International Maritime Organization's (IMO) International Code for Ships Operating in Polar Waters (Polar Code). For similar reasons, an HFO ban in Arctic waters is currently being considered. HFO consists of the remnants or residual of petroleum sources once the hydrocarbons of higher quality are extracted via processes such as thermal and catalytic cracking. Thus, HFO is also commonly referred to as residual fuel oil. The chemical composition of HFO is highly variable due to the fact that HFO is often mixed or blended with cleaner fuels, blending streams can include carbon numbers from C20 to greater than C50. HFOs are blended to achieve certain viscosity and flow characteristics for a given use. As a result of the wide compositional spectrum, HFO is defined by processing, physical and final use characteristics. Being the final remnant of the cracking process, HFO also contains mixtures of the following compounds to various degrees: "paraffins, cycloparaffins, aromatics, olefins, and asphaltenes as well as molecules containing sulfur, oxygen, nitrogen and/or organometals". HFO is characterized by a maximum density of 1010 kg/m3 at 15°C, and a maximum viscosity of 700 mm2/s (cSt) at 50°C according to ISO 8217.
About this result
This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.