The primary purpose of an oil refinery is to separate the varying hydrocarbon chains which crude oil is composed of into usable products such as gasoline, diesel and aviation fuel. Three major processes transform crude oil into petroleum products:
- Distillation
- Conversion
- Purification
Distillation
The first step in the refining process is to separate the different hydrocarbon chains that comprise crude oil. Because hydrocarbons vaporize at different temperatures, crude oil is heated to over 700 degrees Fahrenheit and then is sent to a distillation tower. The temperature decrease as the vapors rise through the tower and the components of the crude oil condense at different heights. Distillation separates the crude oil into unfinished products, some of which must be converted into the products that are demanded by today's consumers.
Conversion
A modern, complex, full conversion refinery will take the heavy unfinished products from the crude distillation unit and turn them into more valuable lighter products such as gasoline and diesel fuel. This is the function of the hydrocracking unit and delayed coker which essentially reduce the length of long hydrocarbon carbon chains.
Purification
Once crude oil has gone through the distillation unit and conversion units, natural impurities must still be removed from the petroleum products. Impurities are removed so that when these fuels are consumed they will burn cleaner. Sulfur is a constituent in most crude oil and it must be removed to produce clean fuels such as ultra-low sulfur gasoline and ultra-low sulfur diesel. This is done so by hydrotreating.
A simplified diagram demonstating the Refining process at the Hyperion Energy Center.
Information is subject to change based on crude slates, site selection and site specific engineering.