1. Petroleum and Gas Processing(TKK-2136) 14/15 Fall semester Instructor: Rama Oktavian Email: rama.oktavian86@gmail.com Office Hr.: M.13-15, Tu. 13-15, W. 13-15, Th. 13-15, F. 09-11

2. Outlines 1. Fluidized Catalytic cracking 2. FCC configuration 3. FCC material balance

3. Fluidized catalytic cracking

4. FCC process The fluidised catalytic cracking (FCC) unit is the heart of the refinery and is where heavy low-value petroleum stream such as vacuum gas oil (VGO) is upgraded into higher value products, mainly gasoline and C3/C4 olefins, which can be used in the alkylation unit for production of gasoline (C7–C8 alkylates). Major developments have occurred in two areas: new catalysts and new reactor and regenerator designs.

5. Fluidized catalytic cracking Role of FCC process  The role of the FCC is to take heavy desulphurised feedstock and crack it into lighter, mainly high octane gasoline.  The FCC also produces olefins (C5+ and C4+) and LPG.

6. Fluidized catalytic cracking FCC feedstock  The main feedstock used in a FCC unit is the gas oil, which can be considered mixtures of aromatic, naphthanic and paraffinic molecules.  There are also varying amounts of contaminants such as sulphur, nitrogen and metals. To protect the catalyst, feed pre-treatment by hydrotreating is required in order to remove contaminants and improve cracking characteristics and yields.

7. Fluidized catalytic cracking FCC feedstock

8. Fluidized catalytic cracking FCC products

9. Fluidized catalytic cracking The VGO undergoes the desired ‘primary cracking’ into gasoline and LCO. A secondary reaction also occurs, which must be limited, such as a hydrogen transfer reaction which lowers the gasoline yield and causes the cycloaddition reaction. The latter could lead to coke formation (needed to provide heat for catalyst regeneration). The main reaction in the FCC is the catalytic cracking of paraffin, olefins, naphthenes and side chains in aromatics.

10. Fluidized catalytic cracking Primary reaction a.Olefins – smaller olefins b. Alkylaromatics – Dealkylation c. Alkylaromatics – Side chain cracking

11. Fluidized catalytic cracking Secondary reaction a.Isomerisation The final product is the transformation of paraffins and olefins to isoparaffins. b. Cyclisation The final result would be the cyclisation of olefins to naphthenes and possibly further cyclisation to coke.

12. Fluidized catalytic cracking FCC reaction summary

13. Fluidized catalytic cracking FCC configuration The basic configuration of the FCC unit is a reactor (riser) and a regenerator.

14. Fluidized catalytic cracking FCC configuration The basic configuration of the FCC unit is a reactor (riser) and a regenerator.

15. Fluidized catalytic cracking Process description riser Steam and VGO heated are fed to the bottom of the riser. The regenerated hot catalyst at is also fed to the bottom of the riser. 316–427 ˚C 649–760 ˚C -endothermic reactions - residence time =2–10 s

16. Fluidized catalytic cracking -Steam is injected into the stripper section, and the oil is removed from the catalyst with the help of some baffles installed in the stripper. - The oil is stripped in this way from the catalyst and the spent catalyst is sent to the regenerator. -The coke in the spent catalyst is burned off in the regenerator by introducing excess air CO, CO 2, H 2 O, Air 482–538 ˚C

17. -Hydrocyclones are installed to catch any solid particles carried out in the overheated stream. -The product gases from the reactor are sent to the fractionator. -The light gases are sent to the gas concentration unit. -The filtered decant can be used as an aromatic solvent or recycled back to the riser with the HCO.

18. Fluidized catalytic cracking Process condition

19. Fluidized catalytic cracking FCC Yield correlation

20. Fluidized catalytic cracking FCC Yield correlation example

21. Fluidized catalytic cracking Solution

22. Fluidized catalytic cracking Solution

23. Fluidized catalytic cracking Material and energy balance in FCC

24. Fluidized catalytic cracking Material and energy balance in FCC