Operators control the refining processes using hi-tech computers located in control centers situated throughout the refinery. Hi-Tech Process Control Using the latest electronic technology to monitor and control the plants, operators run the process units 24 hours a day, 7 days a week. From control rooms located in each Operations area, operators use a computer-driven process control system with console screens that display color interactive graphics of the plants and real-time data on the status of the plants. With redundancy designed into the control system, safe operations are assured in the event of plant upset.
Treatment Separation Modern separation involves piping crude oil through hot furnaces. The resulting liquids and vapors are discharged into distillation units. All refineries have atmospheric distillation units, while more complex refineries may have vacuum distillation units.
Fluid catalytic cracking distillation unit Source: Refining workers overlooking a refinery Source: Inside the distillation units, the liquids and vapors separate into petroleum components called fractions according to their boiling points. Heavy fractions are on the bottom and light fractions are on the top.
The lightest fractions, including gasoline and liquefied refinery gasesvaporize and rise to the top of the distillation tower, where they condense back to liquids. Medium weight liquids, including kerosene and distillatesstay in the middle of the distillation tower.
Heavier liquids, called gas oils, separate lower down in the distillation tower, while the heaviest fractions with the highest boiling points settle at the bottom of the tower. Conversion After distillation, heavy, lower-value distillation fractions can be processed further into lighter, higher-value products such as gasoline.
This is where fractions from the distillation units are transformed into streams intermediate components that eventually become finished products. The most widely used conversion method is called cracking because it uses heat, pressure, catalysts, and sometimes hydrogen to crack heavy hydrocarbon molecules into lighter ones.
A cracking unit consists of one or more tall, thick-walled, rocket-shaped reactors and a network of furnaces, heat exchangers, and other vessels.
Cracking is not the only form of crude oil conversion. Other refinery processes rearrange molecules to add value rather than splitting molecules. Alkylationfor example, makes gasoline components by combining some of the gaseous byproducts of cracking.
The process, which essentially is cracking in reverse, takes place in a series of large, horizontal vessels and tall, skinny towers. Reforming uses heat, moderate pressure, and catalysts to turn naphtha, a light, relatively low-value fraction, into high-octane gasoline components.
Treatment The finishing touches occur during the final treatment. To make gasoline, refinery technicians carefully combine a variety of streams from the processing units.
Octane level, vapor pressure ratings, and other special considerations determine the gasoline blend.• Oil refining is a key activity in the CPI. • Over refineries worldwide have a total annual capacity 6of more than x 10 tonnes.
• Goal of oil refining is twofold: i. production of fuels for transportation, power generation and heating; and ii.
production of raw materials for the CPI. The oil refining process starts with a fractional distillation column. On the right, you can see several chemical processors that are described in the next section.
Very few of the components come out of the fractional distillation column ready for market. The cost of refining oil using the conversion process is somewhat higher than the extraction process. This extra cost incurred by the refiner is eventually passed on to the customer. However, in this case, the customer typically gets what he pays for - a higher quality base oil at a higher initial price.
Petroleum refining processes are the chemical engineering processes and other facilities used in petroleum refineries (also referred to as oil refineries) to transform crude oil into useful products such as liquefied petroleum gas (LPG), gasoline or petrol, kerosene, jet fuel, diesel oil and fuel oils.
You basically heat crude oil up, let it vaporize and then condense the vapor. Newer techniques use Chemical processing on some of the fractions to make others, in a process called conversion. Chemical processing, for example, can break longer chains into shorter ones.
in the refining process is the separation of crude oil into various fractions or straight‐run cuts by distillation in atmospheric and vacuum towers.