Steam, hot water and electricity are used for heating hydrocarbon mixtures in separating columns, preheating crude oil, heating piping systems and in distillation processes such as fractional distillation. 

Steam injection is an increasingly common method of extracting heavy crude oil. It is considered an enhanced oil recovery (EOR) method and is the main type of thermal stimulation of oil reservoirs. There are several different forms of the technology, with the two main ones being Cyclic Steam Stimulation and Steam Flooding. Both are most commonly applied to oil reservoirs, which are relatively shallow and which contain crude oils that are very viscous at the temperature of the native underground formation. 

Another contributing factor that enhances oil production during steam injection is related to near wellbore clean-up. In this case, steam reduces the viscosity that ties paraffins and asphaltenes to the rock surfaces. That while steam distillation of crude oil light ends creates a small solvent bank that can remove miscible trapped oil.