Process units

A refinery is a plant that includes a number of different processing units. Each of these plays a role in the overall process of converting crude oil into finished petroleum products. A typical refinery will have a dozen or more of these processing units. These fall into four broad categories:

  • Separation units - Some process units separate a hydrocarbon mixture into its components through distillation or extraction. The most common separation units are atmospheric distillation and vacuum distillation
  • Conversion units - Conversion units take individual hydrocarbon streams and convert them to other hydrocarbons by changing their size and chemical structure. Examples are the coker, FCC, and alkylation unit
  • Treating units - A number of process unites improve a hydrocarbon stream by removing impurities and changing some chemical properties, but without changing the refinery's product yield. Good examples of this are the hydrotreaters
  • Supporting process units - This includes utilities and and other non-hydrocarbon processing units

Typical process units in a refinery include:

The Refinery Reference Desk includes content derived from our industry experts as well as from public data sources such as company websites. Nothing herein is intended to serve as investment advice. This material is based on information that we believe to be reliable and adequately comprehensive, but we do not represent that such information is in all respects accurate or complete. McKinsey Energy Insights does not accept any liability for any losses resulting from use of the content.



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