Light ends Sweetening & LPG Treating and Fractionation

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Light ends Sweetening

Fraction of unit 

* Removing hydrogen sulfide (H2S) from light gases and cracked gases fromallrefining units. 

* In order to produce sweet fuel gas to heaters then reducing natural gas consumption.

LPG Treating and Fractionation

Function of Unit

* Removing hydrogen sulfide (H2S) and sulfur compounds (Mercaptanes RSH) from LPG produced from Crude atmospheric distillation, Hydrocracking, Delayed coking, FCC and Gasoline reforming.

* In order to produce sweet and stabilized LPG and splitting it into propane & butane. 

* Splitting C3 and C4 is useful to reach the required specification of summer and winter, also C3 is needed for cooling purposes.

Sand Filter

•Function :Sand is used to filter LPG free from entrained caustic before it is fractionated.

•Quality :

-Type : Quartz or silica sand.

- Density: 1600 Kg /m3 .

•Consumption : - Sand is regenerated by water washing when it loses its filtration activity. 

Stabilization and Fractionation of LPG

Stabilization : After LPG treatment LPG fed into deethanizer, in the bottom vapor is generated by the reboiler 

,the vapors travel upwards in the column and pass contact

vapor, de-ethanizer stabilization controls LPG vapor 

trays where they are mixed with the down flowing LPG ,the light ends vaporize from the LPG and take with the flowinglight ends vaporize from the LPG and take with the flowing vapor, de-ethanizer stabilization controls LPG vapor pressure.

Fractionation : The stabilized LPG leaving the bottom of the column is separated into propane and butane by

fractionation this help to control LPG composition at winter and summer, also propane isused atsome coolingsystems.