Mazut a heavy lowquality fuel used in power generating plants and similar applications In the US and Western Europe mazut is blended or broken down with the final product that is diesel The Mazut100 is a fuel that is produced under the GOST specifications for example GOST 1058599 Mazut is almost exclusively manufactured in the Russian Federation Kazakhstan Azerbaijan and Turkmenistan The most important thing is to qualify the fuel sulfur content The VLS Mazut 10075 and 10099 Mazut Grade I are actually the same thing GOST merged the old classifications of 75 and 99 in a new classification of seven degrees all under 10099 For some reason many people still use the old adjective 75 particularly the Chinese