Propane Precooling Cycles for increased LNG train capacity

1. Propane Precooling Cycles for increased LNG train capacity Henri Paradowski , Mohamed Ould Bamba and Christian Bladanet Process Division Technip France LNG 14 Conference , March 2004 Doha , Qatar

2. Propane Precooling cycles for increased LNG capacity Introduction • LNG faces rapid market growth • Today train size is 5 Mtpa of LNG in rundown line • Should this capacity be increased to 6 , 8 or 12 Mtpa? • Is the C3-MR process the most appropriate?

3. APCI C3-MR in split MR line up

4. Propane Precooling cycles for increased LNG train capacity • The C3-MR is robust, efficient and economic • The process invented by APCI has a leading position. • The main challenge is the propane compressor design. • Is it possible to reach 6 Mtpa , 8 Mtpa or more with proven process and equipment ?

5. Basis of study for parametric study • Qatar North Field natural gas composition N2 4.0 %mol C1 87.5 C2 5.5 C3 2.1 C4 0.8 C5 0.1 (No NGL production) • Cooling Water: 29°C • NG flow in MCHE: 0.8 BSCFD

6. Selected turbines and compressors for base case Drivers Available gas turbine site power GE 7 EA 3600 RPM 74 MW GE 9 3000 RPM 106 MW Additional power from helper 9 MW Propane compressor Max. flow coefficient 0.14 Max. volume flow 170 000 Am3/h at impeller eye at 3600 RPM

7. Parametric study to optimize the propane compressor • MR composition • Precooling temperature • MR vaporisation pressure • MCHE outlet temperature Selected parameters

8. Technip Total Nitrogen removal Process : to increase LNG LNG FROM MCHE: 0.8 BSCFD +4.8 % + 6.2 % DRY NG CW NRU RECYCLED GAS GE D NRU GAS TO FUEL 30 bars LNG TO STORAGE: 5.74 MTPA

9. Effect of C1 content in MR Precooling at –34°C , MR vaporization at 4.2 bars

10. Effect of Propane precooling temperature C1 in MR 44.5% , MR vaporization pressure 4.2 bars

11. Effect of MR vaporization pressure Precooling at –31°C , MR C1 44.5 to 45.5%

12. Effect of MCHE outlet temperature Precooling at –31°C, MR : vaporization at 4.4 bars , 45% C1

13. Optimized LNG train with 2 GE 7 Selected parameters for C3-MR process • Methane content in MR 45% • Propane precooling temperature –31°C • MR vaporization pressure 4.4 bars • LNG at MCHE outlet temperature –148°C • LNG production 5.7 Mtpa in run-down line (5.5 Mtpa in storage)

14. Maximum LNG train capacity with a single casing C3 compressor GE9 GE6 + gear GE7 GE5D

15. 8 Mtpa LNG train using C3-MR and GE 7’s How to design an 8 Mtpa LNG train using GE 7’s ? • 3 GE Frame 7 are required How to design the propane cycle of this 8 Mtpa train using The C3-MR process ? • Two line-ups of refrigerant compressors are possible.

16. Line up 1 : 2 // C3-LP MR compressors + 1 HP MR compressor CW CW GT LLP PR HP PR LP MR LP PR MP PR GT CW HP MR TO CHILLERS ASC GT LLP PR LP MR HP PR LP PR MP PR 8 Mtpa LNG train with 3 GE7

17. 8 Mtpa LNG train : C3-MR first line up of compressors • 2 C3-LP MR compressors in parallel • 1 HP MR compressor • From 5.5 to 8 Mtpa the capacity is multiplied by 1.5 • The volume flow of the C3 compressor is multiplied by 0.75 • All volume flow rates are below 170 000 m3/h • All flow coefficients are lower than 0.10

18. Line up 2 : 2// MR compressors + 1 C3 compressor in 2 casings GT CW MR HHP MR LP GT MR LP KA CW GE7 KB CW C3 LIQUID HP C3 MP C3 LLP C3 LP C3 8 Mtpa LNG train with 3 GE7

19. Conclusions on the 8 Mtpa LNG train with 3 GE7 8 Mtpa C3-MR train is feasible and economic 2 possibilities for compressors : • 2 LP MR - propane compressors in parallel and a HP MR compressor • Proven equipment , flexible • 2 MR compressors in parallel and a 2 casing propane compressor • Less costly

20. Capacity increase of an existing C3-MR LNG train Strategy • Target : 30% capacity increase • No modifications to kettles, drums, columns, C3 condensers • Modification of internals • Modification of compressors

21. LNG debottlenecking : Propane Precooling capacity increase HP MR HHP C3 CW M 5B 5B 5B CW CW CW LP MR LLP C3 HP C3 LP C3 MP C3 Compressor line up before modification 67 MW

22. LNG debottlenecking : Propane Precooling capacity increase HP MR HHP C3 CW 5B 5B 5D 5D CW CW CW LP MR LLP C3 MP C3 LP C3 HP C3 Compressor line up after modification : 93 MW New New 5B 5B 5D 5B 5D

23. LNG debottlenecking : Propane Precooling capacity increase Main modifications to compression : Total power increase from 67 to 93 MW : + 26 MW MR compressor turbines : GE5B modified to 5D : +11 MW Propane power : +15 MW New main Propane compressor rotating at 3600 RPM driven by GE5B ( gear box ) New Propane booster compressor driven by GE5B

24. LNG debottlenecking : Propane Precooling capacity increase Concluding remarks : Modification of propane compression is necessary Increase of hydraulic and thermal capacity of some equipment • High efficiency internals in suction drums • High efficiency Wieland tubes in kettles Possible additional savings • Addition of an economizer and creation of a 5th stage on propane compression

25. Propane Precooling Cycles for increased LNG train capacity Conclusions from the studies The C3-MR process can be easily debottlenecked The C3-MR process can be easily designed for a 5.5 Mtpa LNG train using 2 GE7 The C3-MR process can also be designed for a 8 Mtpa LNG train using 3 proven GE7 or 2 GE9 Future Train Is it necessary to increase the train size to 11 Mtpa by using 4 GE7 or 3 GE9 ?

26. Propane Precooling Cycles for Increased LNG train capacity Epilogue The propane cycle is not a limitation to LNG train size The C3-MR process can be used for large trains 8 Mtpa seems to be a good target for the next generation of LNG trains Thank you for your attention