Fluid Catalytic Cracking
Fluid Catalytic Cracking
Fluid catalytic cracking* (FCC) is the most important conversion process used in petroleum refineries. It is widely used to convert the high-boiling hydrocarbonfractions of petroleum crude oils into more valuable
[1][2][3]
gasoline, olefinic gases and other products.
. Cracking of petroleum hydrocarbons for conversion of heavy fractions into lighter fractions was originally done by thermal cracking which has been almost completely replaced by catalytic cracking because it produces more gasoline with a higher octane rating.
It also produces byproduct gases that are more olefinic, and hence more valuable, than those produced by thermal cracking.
The feedstock to an FCC is usually that portion of the crude oil that has an initialboiling point of 340 ° or
C
higher at atmospheric pressure and an average molecular weight ranging from about 200 to 600 or higher. The FCC process vaporizes and breaks the long-chain molecules of the high-boiling hydrocarbon liquids into much shorter molecules by contacting the feedstock, at high temperature and moderate pressure, with a fluidized powdered catalyst.
In effect, refineries use fluid catalytic cracking to correct the imbalance between the market demand for gasoline and the excess of heavy, high boiling range products resulting from the distillation of crude oil.
As of 2006, FCC units were in operation at 400 petroleum refineries worldwide and about one-third of the
crude oil refined in those refineries is processed in an FCC to produce high-octane gasoline and fuel
[4][5]
oils.
During 2007, the FCC units in the United States processed a total of 834,300,000 litres
[6]
(5,300,000 barrels) per day of feedstock and FCC units worldwide processed about twice that amount.
Flow diagram and process description:
The modern FCC units are all continuous processes which operate 24 hours a day for as much as 2 to 3 years between shutdowns for routine maintenance.
There are a number
Fluid catalytic cracking* (FCC) is the most important conversion process used in petroleum refineries. It is widely used to convert the high-boiling hydrocarbonfractions of petroleum crude oils into more valuable
[1][2][3]
gasoline, olefinic gases and other products.
. Cracking of petroleum hydrocarbons for conversion of heavy fractions into lighter fractions was originally done by thermal cracking which has been almost completely replaced by catalytic cracking because it produces more gasoline with a higher octane rating.
It also produces byproduct gases that are more olefinic, and hence more valuable, than those produced by thermal cracking.
The feedstock to an FCC is usually that portion of the crude oil that has an initialboiling point of 340 ° or
C
higher at atmospheric pressure and an average molecular weight ranging from about 200 to 600 or higher. The FCC process vaporizes and breaks the long-chain molecules of the high-boiling hydrocarbon liquids into much shorter molecules by contacting the feedstock, at high temperature and moderate pressure, with a fluidized powdered catalyst.
In effect, refineries use fluid catalytic cracking to correct the imbalance between the market demand for gasoline and the excess of heavy, high boiling range products resulting from the distillation of crude oil.
As of 2006, FCC units were in operation at 400 petroleum refineries worldwide and about one-third of the
crude oil refined in those refineries is processed in an FCC to produce high-octane gasoline and fuel
[4][5]
oils.
During 2007, the FCC units in the United States processed a total of 834,300,000 litres
[6]
(5,300,000 barrels) per day of feedstock and FCC units worldwide processed about twice that amount.
Flow diagram and process description:
The modern FCC units are all continuous processes which operate 24 hours a day for as much as 2 to 3 years between shutdowns for routine maintenance.
There are a number