1. Lube Oil Base Stocks (LOBS) Future Plans For Group II / III

2. OUT LINE Base Oil production Details of LOBS Processing schemes
LOBS quality
Basics of LOBS Manufacturing Technologies
Details of LOBS Processing schemes
Observations & Conclusions

3. LOBS Quality Present LOBS quality fall under API Group I. Spindle
Appearance
B&C VI
98-100
95-97
Pour point C -6 -1
Color, ASTM
0.5
<1.0
<2.5
<3.5
Sulphur, wt%
0.8– 0.9
Saturates, wt% NA
@ 67
@ 65
Present LOBS quality fall under API Group I.

4. LOBS Quality American Petroleum Institute (API) LOBS Categories
API Sats Sulfur VI Typical Manufacturing Process
I <90% >0.03% Solvent Processing
II >90% <0.03% Hydroprocessing
III >90% <0.03% Wax Isomerisation
IV n.a n.a Polyalphaolefins (PAO)
V All other Basestocks
American Petroleum Institute (API) LOBS Categories

5. LOBS Quality
API specs are not regulatory as in case of automotive fuels, but are set by market & customer requirements.
API specs are very broad.
What level of API specs the LOBS need to comply with?
A refiner may meet the bare minimum saturates as per Group II (90%) and yet may not meet market demand for 99% saturates.

6. LOBS Quality
The refiner with this situation must address many questions.
What are the target specs of each product?
What are the various technology options available?
Product slate (Grades of LOBS & whether wax is a product or not?)
Integration of Lube block & Fuel block
How doest it affect the over all profitability?

7. Base oil Manufacturing Technology
Crude Source
V.I. Upgrading
Dewaxing
Finishing
Base Oil
Low pressure Hydrotreating
Conventional
Solvent Refining
Solvent Dewaxing
Modern
Hydrocracking
CatalyticDewaxing
Hydrofinishing
Hydrofinishing
Alternate
Hydrocracking
Isodewaxing/MSDW
Solvent Refining/ Hydrotreating
Isodewaxing/MSDW
Alternate
Hydrofinishing

8. Base oil Manufacturing Technology
Crude Source
Base Oil
Hydrocracking/Hydrotreating
Dewaxing
Noble Metal HF
Hydrocracking/Hydrotreating
High Yield
Feed Flexibility
Satisfy Fuel & Lubes Demand
HCR/HDT boosts V.I. By converting low V.I. components to high V.I. base oils and also by cracking low V.I. components to lower boiling ranges----- Solvent refining simply removes low V.I. Aromatic components

9. Base oil Manufacturing Technology
Crude Source
Base Oil
Hydrocracking/Hydrotreating
Dewaxing
Noble Metal HF
Isodewaxing(IDW, CLG)/Mobil Selective Dewaxing (MSDW, EMRE)
High V.I. Retention resulting in higher overall Yield for Lube train
Ability to handle high wax feeds such as Slack wax.
IDW/MSDW reduces pour point primarily by Catalytic Wax Isomerization, giving higher overall product Yield and V.I. Than Solvent Dewaxing or conventional Catalytic Dewaxing.

10. ISODEWAXING Isomerization With Minimum Branching Maintains V. I
ISODEWAXING Isomerization With Minimum Branching Maintains V.I. and Lowers Pour Point
V.I
Melting Point, oC
N-Paraffin
I-Paraffin r
C20
174
164
36.6
-2.5
39.1
C30
156.5
143 66
8.6
57.4
Example of how isomerization can lower pour point, yet maintain high VI

11. Comparison of Dewaxing Processes
Solvent Dewaxing
Catalytic Dewaxing
IDW/MSDW
Wax removal
Product Pour Point
Yields
Dewaxed Product V.I.
By – Products
Operating costs
Physical – Wax Crystallization and filtration
-10 to –15 o C
Base Case
Slack wax
Base (100%)
Chemical – wax Cracking with shape selective catalyst
-10 to –50 o C
Same or Lower
Generally 5 –10 Numbers Lower
Gas, Naphtha
50 –60 %
Chemical – wax Isomerization with shape selective catalyst
Same or Higher
Generally 5 –10 Numbers Higher
Gas, Naphtha, Jet, Diesel
55 – 65%
Comparison of Dewaxing Processes

12. Isodewaxing preserves V.I. and viscosity of waxy oil.
Product Comparison of Different Dewaxing Processes – Constant Refining Severity
IDW/MSDW
SDW
V.I
Waxy V.I.
CDW
Dewaxed V.I.
Dewaxed Viscosity
CDW
Viscosity
Waxy Viscosity
SDW
IDW/MSDW

13. ISODEWAXING During the Dewaxing Step, Wax Molecules Are Either Removed, Cracked, or Converted
Example: nC20, 174 V.I., Melting Point 37 oC
^^^^^^^^^^^^^^^^^^^^^^^^^
Isodewaxing/MSDW
Solvent Dewaxing
Conventional Catalytic
Dewaxing
^^^^^^^^^^
^ + ^^
C C4, C5, C6
^^^^^^^^^^^
iC20: 164 V.I., Melting Point –2.5oC
Wax
Wax Cracked to Light gases & Naphtha
Wax Isomerized to Lube Oil
Wax separated from Oil

14. Existing Refinery – Over view
Integrated Lube and Fuel complex which operate in tandem
Segregated crude/vacuum units which process low sulfur/non lube bearing and lube bearing crudes.
Fuel Block
Fluid Catalytic Cracking (FCC)
Diesel Hydrodesulphuriser
Lube Block
Extraction units
Hydrofinishing units
Solvent dewaxing unit

15. SIMPLIFIED REFINERY- EXISTINGC D U 1
SIMPLIFIED REFINERY- EXISTING
LPG
High Sulfur Crude
NAPHTHA
CDU 2
DHDS
DIESEL
Low Sulfur Crude F C
GASOLINE
VDU 1
SR Naphtha H2 H2
FUELS BLOCK S E U S D U
SPINDLE V DU 2
150 N
500N V DU 3 BS
LUBE
BLOCK
IO-100
DAO
PDA VR
IO-1600

16. LUBE REFINERY PROCESS UNITS
TOBS
SEU
VDU
150N PG
LOBS
500N
P DU
RCO
( 3 Nos )
1300N BS
IOH
IO-100
PDA
VTB
ASPHALT

17. Base Oil Processing Scheme- Existing
Group I Base Oil
Extracts
Spindle Raffinate
VPS
Spindle
EXTRACTION
NMP S DU
Spindle
SS-I
150 N Raffinate
150 N
SS-II
500 N
500 N Raffinate
BS Raffinate BS
IO-100
IO-100
SDA
IO- 1600
IO -1600
DAO
Notes
Arab Mix Crude processed in Lube block

18. VACUUM DISTILLATION UNIT
DISTILLATION IS SEPARATION OF PRODUCTS BY DIFFERENCE IN BOILING POINT
DISTILLATION OF REDUCED CRUDE OIL UNDER VACUUM
SEPARATION UNDER VACCUM TO AVOID DECOMPOSITION OF CRUDE
MAIN PRODUCTS ARE VACUUM GAS OIL, DISTILLATES FOR LUBES & VTB.
COLOR, VISCOSITY, FLASH POINT OF SIDESTREAMS AND VTB PEN ARE MONITORED.

19. SOLVENT EXTRACTION UNIT
REMOVAL OF AROMATICS FROM DISTILLATE USING NMP AS SOLVENT BY LIQUID - LIQUID EXTRACTION PROCESS . ORIGINALY PHENOL WAS USED AS SOLVENT.
IMPROVES VISCOSITY INDEX.
IMPROVES COLOR, THERMAL & OXIDATION STABILITY.
REDUCES AROMATIC CONTENT

20. HYDROFINER UNIT FIXED BED CATALYTIC HYDROGENATION PROCESS
HYDROGEN IS USED AS TREAT GAS
IMPROVES COLOR,COLOUR STABILITY, OXIDATION STABILITY.
REDUCES SULPHUR & NITROGEN CONTENT

21. PROPANE DEWAXING UNIT PHYSICAL SEPARATION PROCESS
WAX IS CRYSTALLISED AT LOW TEMPERATURES AND REMOVED BY FILTERING IN ROTARY DRUM FILTERS
PROPANE IS USED AS SOLVENT AND AUTOREFRIGERANT.
IMPROVES THE POUR POINT OF LUBE OIL BY REMOVING WAX

22. PROPANE DEASPHALTING UNIT
PRODUCES DE ASPHALTED OIL BY REMOVING ASHPHALT FROM VACUUM TOWER BOTTOMS (VTB)
ASPHALT REMOVAL CARRIED OUT BY COUNTERCURRENT LIQUID - LIQUID EXTRACTION
PROPANE USED AS SOLVENT
PRODUCES HIGH QUALITY BRIGHT STOCK OR FEEDSTOCK FOR FCC UNIT AND ASPHALT FROM VTB.
DECREASES ASPHALTENE, RESIN, CARBON RESIDUE, SULPHUR AND NITROGEN CONTENT.
IMPROVES COLOUR

23. Existing LOBS Processing scheme
Solvent Extraction Units (SEU) + Hydrofinishers + Solvent Dewaxing unit
Multiple units (SEU & HF) are provided to allow simultaneous processing of different grades.
No wax production is considered. Slack wax is processed in FCC.
DAO from SDA is processed in SEU & SDU to produce BS.

24. Existing LOBS Processing scheme
Present quality of LOBS (especially Sulfur & saturates ) are far away from Group II specifications.
Existing Hydrofinishers are low pressure (58 bar) and hence are not suitable for meeting Group II specs.
Even with deeper extraction level of aromatics & sulfur can not be of Group II quality
Production of Group II base oils require some form of hydroprocessing route.

25. Demand Pattern Demand Pattern Setting Demand Pattern
Total make
200,000 TPA
300,000 TPA
API category
Remarks
Base Oil
(‘000 TPA)
Spindle 15
Group II
Saturates >99%
150 N 25 80
500 N
115
160
IO-100 5
Group I/Present
IO-1600 BS 35
Total Group II base oils
155
255

26. Base oil Upgrading scheme -1 Group –II oils 255, 000 TPA
Add a New 150 bar Hydrotreater (HDT) to existing scheme.
Raffinates from existing SEU are processed in a high pressure hydrotreater.
Hydrotreated raffinates are further processed in existing Solvent Dewaxing unit.

27. Base Oil Upgrading Scheme- 1
Group II Base Oil : 255,000 TPA
Distillate to fuel Complex
Extracts
Spindle Raffinate
VPS
Spindle
EXTRACTION
NMP
HDT (150 bar)
350,000 S DU
Spindle 15,000
SS-I
150 N ,000
150 N Raffinate
SS-II
500 N ,000
500 N Raffinate
BS ,000
IO ,000
SDA
IO-100
IO ,000
IO- 1600
DAO
Notes
Arab Mix Crude processed in Lube block
2) VI of 500N 104

28. Base oil Upgrading scheme -1 Group –II oils 255, 000 TPA
Findings of the scheme.
Advantages:
Base oils meet all the bare minimum Group II specs.
Aromatic levels in base oils, especially 500 N will be around 10%. (disadvantage?)
Aromatics in 150 N will be around 5% (disadvantage?)

29. Base oil Upgrading scheme -1 Group –II oils 255, 000 TPA
Findings of the scheme.
Disadvantages:
Yield loss (for 500 N) from HDT is significant, for the same LOBS production, raffinate feed reqmt is more and hence higher HDT unit capacity.
Higher capital cost because of higher HDT capacity

30. Base oil Upgrading scheme -2 Group –II oils 255, 000 TPA
Add a New 150 bar Hydrotreater (HDT) + New Hydroisomerisation (HDW) unit to existing scheme.
Raffinates from existing SEU are processed in a high pressure hydrotreater.
Hydrotreated raffinates are further processed a new Hydroisomerisation unit.
Other Base oils are processed in conventional route.

31. Base Oil Upgrading Scheme- 2 Group-II Base Oils : 255,000 TPA
Distillate to fuel Complex
Extracts
Spindle Raffinate
VPS
EXTRACTION
NMP
HDT (150 bar)
289000
HYDRO ISOM/
HYF
Spindle
Spindle 15,000
SS-I
150 N Raffinate
150 N ,000
SS-II
500 N Raffinate
500 N ,000
SDA
BS BS ,000
SDU
IO-100
IO ,000
DAO
IO- 1600 IO
Notes
Arab Mix Crude processed in Lube block
2) VI of 500N 104

32. Base oil Upgrading scheme -2 Group –II oils 255, 000 TPA
Add a New 150 bar Hydrotreater (HDT) + New Hydroisomerisation unit to existing scheme.
Hydroisomerisation catalyst is noble metal catalyst and can tolerate low levels of Nitrogen & other contaminants
Hydrotreater prepares the feed for this unit.
Hydroisomerisation unit upgrades this feed by converting wax to high value VI base oils.
Hydrofinishing step is included in this scheme.

33. Base oil Upgrading scheme -2 Group –II oils 255, 000 TPA
Findings of the scheme.
Advantages:
Base oils meet or exceed all Group II specs.
Aromatic levels in base oils < 1 %
Yield loss in HDT compensated in HDW unit.
Lower raffinate feed reqmt less than scheme-1.
Lower raffinate feed reqmt increases the feed to FCC unit.

34. Base oil Upgrading scheme -2 Group –II oils 255, 000 TPA
Findings of the scheme.
Advantages:
The pressure levels of HDT & HDW can be kept same to facilitate integrated operation and both units will have a single recycle loop.
Lower capital cost than scheme-1.
Provides flexibility for staged investment. Implement scheme-1 and at a later stage integrate HDT with HDW.

35. Base oil Upgrading scheme -2 Group –II oils 255, 000 TPA
Findings of the scheme.
Disadvantages:
Destroys wax. In this particular case, wax is not a product.

36. Base oil Upgrading scheme -3 Group –II oils 255, 000 TPA
Add a New 150 bar Hydrotreater (HDT) + New Hydroisomerisation (HDW) unit for slack wax
Raffinates from existing SEU are processed in a high pressure hydrotreater.
Slack wax from SDU is processed in a new Hydroisomerisation unit.
Other Base oils are produced in conventional route.

37. Base Oil Upgrading Scheme- 3
Group II Base Oil : 255,000 TPA
Distillate to fuel Complex
Extracts
Spindle Raffinate
VPS
Spindle
EXTRACTION
NMP
HDT (150 bar)
350,000 S DU
Spindle 15,000
SS-I
150 N ,000
150 N Raffinate
SS-II
500 N ,000
500 N Raffinate
BS ,000
IO ,000
IO-100
SDA
IO ,000
IO- 1600
DAO
Slack wax 100,000
HDW/HF
Notes
150 N 70,000
Arab Mix Crude processed in Lube block
Group III
2) VI of 500N 104

38. Base oil Upgrading scheme -3 Group –II oils 255, 000 TPA
Findings of the scheme.
Advantages:
Base oils from SDU meet bare minimum Group II specs.
Slack wax processed in HDW produces 150 N of Group III.
Maximum utilization of SDU capacity
Option for staged investment.

39. Base oil Upgrading scheme - 3 Group –II oils 255, 000 TPA
Findings of the scheme.
Disadvantages:
Aromatic levels in 500 N will be around 10%.
Higher capital cost because of high RHT unit capacities & wax Isomerisation unit.

40. Base oil Upgrading scheme -4 Group –II oils 255, 000 TPA
New Hydrocracker + New Hydroisomerisation
All side streams from VDU are routed to Lube hydrocracker (LHCU).
The waxy streams from LHCU processed in HDW.
LHCU also produces hydrocracked VGO (non-lube material) which is routed to FCC.

41. Base Oil Upgrading Scheme- 4 Group II Base Oil : 255,000 TPA
360ºC & lighter
Light Feed
Heavy
<360ºC
Lube Hydrocracker
Blocked Operation 1340,000 TPA
290,000 TPA
HDW
Diesel
Spindle Oil
Spindle
Streams
150 N
Waxy 150N
500N
VDU
Side
Streams
Waxy 500N
Heavy Feed
Hydrocracker DS VGO
0.005% Sulfur
FCCU
870,000
Notes
Arab Mix Crude processed
2) VI of 500N > 120

42. Base oil Upgrading scheme -4 Group –II oils 255, 000 TPA
Findings of the scheme.
Advantages:
Flexibility to process higher volumes of high sulfur crudes. Greatest crude flexibility.
Base oils exceed Group II quality.
FCC feed quality has significantly improved which results in high yields of value distillates such as LPG, gasoline.
Quality of FCC products w.r.t sulfur significantly improves.

43. Base oil Upgrading scheme - 4 Group –II oils 255, 000 TPA
Findings of the scheme.
Disadvantages:
High Hydrogen consumptions and hence additional hydrogen plant required.
Existing Lube processing facilities become redundant.
Highest capital costs.

44. Utilization of Existing Lube processing facilities
Existing 60 bar Hydrofinishers.
The pressure levels of HDT & HDW are around 150 bar.
Existing HF can not be used because the product quality as measured by aromatics and color would actually degrade by using these HF
Existing Solvent Dewaxing Unit:
In scheme-2 only BS & IO’S are processed in SDU. This results in underutilization of SDU.
Reduce the 500 N Group II requirements. Utilize the existing scheme to produce 500 N, BS & IOs of Group I quality.
This will allow the refiner the greatest flexibility to produce Group I as well as Group II depending on market demand.

45. Integration of Hydroprocessing and Solvent Extraction
Hydroprocessing can be Integrated with Solvent Extraction plants to improve product Quality/Yield & flexibility to make Group II/III Oils
SEU
SDW HF
Group I
Slack Wax/Soft Wax
Raffinate
Group III
HDT
Hydro ISOM
HDF
Group II

46. Base Oil Upgrading Scheme- 5 Group-II Base Oils : 155,000 TPA
Distillate to fuel Complex
Extracts
Addl feed to FCC
Spindle Raffinate
VPS
EXTRACTION
NMP
HDT (150 bar)
176000
HYDRO ISOM/
HYF
Spindle
150 N ,000
SS-I
150 N Raffinate
Spindle 15,000
SS-II
500 N Raffinate
500 N ,000
SDA
BS Raffinate BS ,000
SDU
IO-100
DAO
IO ,000
IO- 1600 IO
Notes
Arab Mix Crude processed in Lube block
2) VI of 500N 104

47. Observations & Conclusions
If an Extraction unit is present, it is more economical to produce Group II LOBS via raffinate HDT route.
Staged investment is an option for the refiner. In the first phase HDT can be considered and at a later stage Hydro Isom can be added.

48. Observations & Conclusions
Quantity of 500 N affects the over all economics. Since the trend is to move towards lighter viscosity grades, refiner has to judiciously decide the break up of Group I & Group II.
Consider VI of LOBS (especially 500 N with in Group II). Increasing the VI beyond Group II requirements will reduce the yields, increase the capital investments and hence not economical.
While revamping the FCC unit, consider additional feed in FCC unit, keeping in view the fluctuating demand of LOBS.

49. Observations & Conclusions
Can LOBS quality improvement alone justify investment?
This is a difficult question to answer.
With 255,000 TPA of Group II LOBS, revenues are better but these do not give better IRR because of higher capital costs & impact on Fuel block products.
With 155,000 of Group II LOBS, IRR could be better. Thus each refiner should evaluate the economics based on target LOBS production.
While maximizing LOBS production, consider maximizing value added products such as LPG from FCC etc. to improve over all refinery profitability.

50. THANK YOU