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How is bitumen produced in a petroleum refinery?

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Aerial view of an oil refinery complex near New Orleans, Louisiana, with storage tanks, industrial structures, and smoke rising from the facility, surrounded by open land. — petroleum refining Aerial view of an oil refinery near New Orleans.

In a petroleum refinery, refined bitumen is produced as a heavy residue through the process of vacuum distillation.12

During this process, crude oil is heated and processed in large-diameter columns operating at reduced pressures (typically 50 to 100 mm of mercury). By lowering the pressure, refineries can distill heavier materials at temperatures below those that would cause thermal cracking, generally keeping furnace temperatures below 425 °C (800 °F).2

The material that remains at the bottom of the vacuum distillation column after the lighter components have been vaporized and removed is bitumen. This residue can then be further processed or blended to create products such as road asphalt or residual fuel oil, or it may serve as a feedstock for additional conversion units like coking or thermal cracking.21