Home heating fuel viscosity

Fuel Oils Any liquid or liquifiable petroleum product burned for the generation of heat in a furnace or firebox or for the generation of power in an engine, Typical fuels include clean distillate fuel for home heating and higher-viscosity residual fuels for industrial furnaces. 

Residual fuel oil, the bottom fraction of the distillation colunrn, contains most of the undesirable sulfur, metals, and carbon deposits from crude oil. It has a very high viscosity and can solidify in cold weather. Its use requires high-pressure nozzles and heated containers, making it unsuited for home heating. It is primarily used in industrial, utility, and marine boilers. 

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