The Refining Process

Oil refining is the process of separating the hydrocarbon molecules present in crude oil and converting them into marketable, finished petroleum products, such as diesel fuel, gasoline and home heating oil.

A refinery is a complex factory. Like a paper mill that makes paper out of pulp, our refineries take crude oil and turn it into gasoline, diesel, jet fuel and many other products. How does the refining process work?

Refining Flow - click to enlarge

The refining process is basically as follows: crude oil is first distilled in a crude distillation unit (CDU). The CDU produces a number of basic products: liquefied petroleum gas, naphtha, kerosene, gas oil and fuel oil. These basic products are then further processed in upgrading units.

A refinery performs three basic steps: separation, conversion, and treatment. Each function in the refining process is designed to maximize the value of the refined petroleum products produced. Refineries run twenty-four hours a day and require a large number of dedicated employees to operate.

As a general rule, the more upgrading units a refinery has, the more complex it is. Complex refineries usually have a higher replacement value but they also yield a higher margin.

Refining Flow - Click picture to enlarge