VACUUM
Vacuum in the context of petroleum derivatives refers to the vacuum distillation process, which is a key technique used in the refining of crude oil. It is part of the overall refining process, specifically following atmospheric distillation, and is essential for separating heavier fractions of crude oil that cannot be distilled at atmospheric pressure. Vacuum distillation operates under reduced pressure (vacuum), allowing the separation of high-boiling-point hydrocarbons without decomposing them.
Vacuum Distillation in Petroleum Derivatives:
1. Process:
• After crude oil is initially distilled in an atmospheric distillation column, the remaining heavier fractions, such as residuum, are sent to a vacuum distillation unit.
• In a vacuum distillation column, the pressure is lowered significantly (below atmospheric pressure), allowing the heavy hydrocarbons to vaporize at much lower temperatures than they would under normal pressure conditions.
2. Fractions Produced:
• Light vacuum gas oil (LVGO): Used in the production of diesel and as feedstock for cracking processes.
• Heavy vacuum gas oil (HVGO): Used in the production of more valuable fuels or as feedstock for catalytic cracking to produce gasoline or diesel.
• Vacuum residuum: A very heavy and viscous product that can be used for asphalt, lubricants, or as feedstock for further refining processes like coking or hydrocracking.
3. Importance:
• Vacuum distillation is crucial for obtaining valuable middle and heavy petroleum products that are not available through atmospheric distillation alone.
• It enables the production of high-value fuels like diesel and high-quality lubricants and also serves as the foundation for further upgrading processes, such as cracking and hydrocracking.
