Fluidized cataltic cracking.

A presentation by - vivek bhargude (BE Chemical)

1. Pad. Dr. D.Y. PATIL College of Engineering, Management & Research, Akurdi . DEPARTMENT OF CHEMICAL ENGINEERING, PRESENTATION ON FLUIDIZED CATALYTIC CRACKING Guidance DR. SWAPNIL DHARASKAR Presented by vivek d. bhargude

2. Content What is FCC? General Overview Of FCC: a) Reactor b) Regenerator Process Description Advantages and Disadvantages CASE STUDY

3. What is FCC? FCC “heart” of the Modern Refineries it Contributes the Highest volume to the Gasoline pool One of the most important & sophisticated contributions to petroleum refining technology Primary conversion process in the petroleum refinery The purpose is to convert high-boiling petroleum fractions (gas oil) to high-value, high-octane gasoline and heating oil. Zeolite catalyst is used when properly aerated

4. General Overview of FCC The FCC assembly consists of reactor and regenerator. Further the product coming from FCC unit is charged to the Fractionator. Regenerator helps to reactivate the catalyst and reactivation of catalyst is done using the hot air or by passing the steam through the regenerator

5. FCC Reactor-Regenerator

6. Description of the Process Reactor Riser Cyclone Stripper Regenerator Stand pipe and Slide valve

7. REACTOR THE REACTOR USED IN CASE OF FCC IS THE FLUIDIZED BED REACTOR THAT WORKS ON THE PRINCIPLE OF FLUIDIZATION. THE FEEDSTOCK IS FED AT THE BOTTOM AND THE FINAL PRODUCT IS TAKEN OUT FROM THE TOP SECTION. THE RACTOR HAS THE CATALYTIC BED ARRANGEMENT INSIDE IT OVER WHICH THE CATALYST IS SPREAD.

8. Riser Dimensions Diameter: 1.2 m (4 ft) Height : 36.6 m (120 ft) Plug flow with minimum back-mixing Steam is used to atomize the feed Increases the availability of feed

9. Cyclones Located at the end of the riser to separate the bulk of the catalyst It can be used as the deflector to turn the direction of catalyst to separate the remaining of the Catalyst in the regenerator.

10. Stripper The spent catalyst falls into the stripper Some valuable Hydrocarbons are absorbed within the catalytic bed steam at a rate of 4 Kg per 1000 Kg of catalyst is used to strip the hydrocarbon from the catalyst

11. Regenerator Two functions: 1.Restores catalyst activity 2.Supplies heat to crack the feed Air is the source of oxygen for the combustion of coke The air blower with 1m/s (3 ft/s) air velocity to maintain the catalyst bed in a fluidized state 14 kPa (2 psi) pressure drop in air distributors to ensure positive air flow through all nozzles

12. Standpipe & Slide Valve The catalyst density in standpipe is 642 kg/m 3 (40 lbs/ft 3 ) Standpipe provides the necessary pressure head needed to circulate the catalyst around the unit. Slide valve is used to regulate the flow rate of the regenerated catalyst to the riser Slide valve function is to supply enough catalyst to heat the feed and achieve the desired reactor temperature

13. Advantages and Disadvantages Advantages No need to add the hydrogen to reduce the coke formation Could be routed to hydrocracker to produce diesel Coke production is small but very important as it will helpful for providing the heat for the cracking of reaction Disadvantages Desulfurisation is to be done properly for the prevention of formation of poisonous catalyst Low Cetane number The products coming out from the reactor sometimes have same boiling range so azeotropic distillation is to be done in the Fractionator

14. Case study Jiddah Refinery/FCC Catalyst selectio n OBJECTIVE : To implement a program that results in the cost-effective management of catalysts and desiccants for the company.

15. FEEDSTOCK PROPERTIES Feed Rate, MBPD : 20 Feed Stock Gas Oil : (240 – 630 CELCIUS) Specific gravity : 0.91 Sulphur wt. : 2.6% Carbon wt. : 0.24% Refractive index : 1.52 Viscosity : cSt26

16. OPERATING CONDITIONS Combined Feed T , :235 DEG.CELSIUS ROT, :514 DEG.CELSIUS Flue Gas T , : 736 DEG.CELSIUS • Reg . CATALYST, : 689 DEG.CELSIUS Cat . Circulation , : 16 ton/min Catalyst addition rate , : 1.0 TPD

17. LAB SCALE RESULT

18. Conclusions Stripping steam of 4 kg per 1000 kg circulating catalyst is required. Overall endothermic Heat of Reaction is 86 MBtu/hr. Pressure buildup in spent catalyst standpipe is 27 kPa (4 psi). Pressure buildup in regenerated catalyst standpipe is 55 kPa (8 psi).

19. REFERENCE A HANDBOOK ON PETROLEUM REFINERY ‘ B. K. BHASKARRAO’ Catalyst Management Protocols in Saudi Aramco www3.kfupm.edu.sa/catsymp/symp16th/pdf%20papers/13alloush.pdf

20. THANK YOU