The distillation of the ‘Light Ends’ from crude oil

The ‘light ends’ unit is the only process in a refinery configuration that is designed to separate ‘almost’ pure components from the crude oil. Its particular growth has resulted from the need of those components such as the butanes and propanes to satisfy a market of portable cooking fuel and industrial fuels. That these products can be suitably compressed and stored in small, easily handled containers at ambient temperatures provided the market popularity for these products, suitably titled Butane LPG and Propane LPG. The term LPG referring to Liquefied Petroleum Gas.

The introduction of the ‘No Lead’ in gasoline program during the late 1960s set the scene for the need of Octane sources additional to the Aromatics provided by high severity catalytic reforming. A source of such high-octane additives is found in some isomers of butane and pentane. This added to the need for light end processes which in many cases included the separation of iso butanes from the butane stream and also iso pentanes from the light naphtha stream.