Mazut is a heavy, low quality fuel oil, used in
generating plants and similar applications. In
the United States and Western Europe, mazut is
blended or broken down, with the end product
being diesel. Mazut-100 is a fuel oil that is
manufactured to GOST specifications, for example
GOST 10585-99. Mazut is almost exclusively
manufactured in the Russian Federation,
Kazakhstan, Azerbaijan, and Turkmenistan. The
most important thing when grading this fuel is
the sulphur content.
Mazut 100-75 VLS and Mazut 100-99 Grade I are
actually the same thing. GOST merged the old
classifications of 75 and 99 into a new seven
grade classification, all under 100-99. For
whatever reason, many people still use the old
75 classification; particularly the Chinese.
The grades are represented by these sulphuric
levels:
”Very Low Sulphur” is mazut with a sulphur
content of 0.5% ”Low Sulphur” is a mazut
with a sulphur content of 0.5-1.0% ”Normal
Sulphur” is a mazut with a sulphur content of
1.0-2.0% ”High Sulphur” is a mazut with a
sulphur content of 2.0-3.5%.