Marine diesel oil

Marine Diesel Oil (MDO) is a type of fuel oil and is a blend of gasoil and heavy fuel oil, with less gasoil than intermediate fuel oil used in the maritime field. Marine Diesel Oil is also called "Distillate Marine Diesel". MDO is widely used by medium speed and medium/high speed marine diesel engines. It is also used in the larger slow speed and medium speed propulsion engine which normally burn residual fuel. Those fuels resulting from a catalytic cracking/visbreaking refinery. Marine diesel oil has been condemned for its nimiety of sulfur, so many countries and organizations established regulations and laws on MDO use. Due to its lower price compared to more refined fuel, MDO is favored particularly by shipping industry.

Specification

ISO 8217 of the International Standards Organization (ISO) is the primary standard of MDO.

Marine fuels range in viscosity from less than one centistoke (see viscosity) (cSt) to about 700 cSt at 50°C (122°F). (1 cSt = 1 mm2/s.) And higher viscosity grades are preheated during use to bring their viscosity into the range suitable for fuel injection (8 to 27 cSt). But MDO does not need to be preheated before using. According to Chevron, MDO has a sulfur limit varies from 1 to 4.5 percent by mass for different grades and Sulfur Emission Control Areas (SECAs).

Diesel fuel

Diesel fuel /ˈdiːzəl/ in general is any liquid fuel used in diesel engines, whose fuel ignition takes place, without spark, as a result of compression of the inlet air mixture and then injection of fuel. (Glow plugs, grid heaters and heater blocks help achieve high temperatures for combustion during engine startup in cold weather.) Diesel engines have found broad use as a result of higher thermodynamic and thus fuel efficiencies. This is particularly noted where diesel engines are run at part-load; as their air supply is not throttled as in a petrol engine, their efficiency still remains very high.

The most common type of diesel fuel is a specific fractional distillate of petroleum fuel oil, but alternatives that are not derived from petroleum, such as biodiesel, biomass to liquid (BTL) or gas to liquid (GTL) diesel, are increasingly being developed and adopted. To distinguish these types, petroleum-derived diesel is increasingly called petrodiesel.Ultra-low-sulfur diesel (ULSD) is a standard for defining diesel fuel with substantially lowered sulfur contents. As of 2016, almost all of the petroleum-based diesel fuel available in UK, Europe and North America is of a ULSD type. In the UK, diesel fuel for on-road use is commonly abbreviated DERV, standing for diesel-engined road vehicle, which carries a tax premium over equivalent fuel for non-road use (see Taxation). In Australia diesel fuel is also known as 'distillate'.