Technology for Producing Clean Diesel Utilizing Moderate Pressure Hydrocracking With Hydroisomerization

Transcription

1 Technology for Producing Clean Diesel Utilizing Moderate Pressure Hydrocracking With Hydroisomerization XIII Refining Technology Forum IMP-Pemex Pemex Refinacion Mexico City, Mexico November 14, 2007 J. F. Stanley W. J. Tracy ExxonMobil Research and Engineering Company (EMRE) Vasant Patel Anand Subramanian -

2 Outline Overview of selected ExxonMobil technologies MPHC for plus production of diesel Use of post treat units to adjust diesel properties through HDT,HDC and Hydroisomerization (MIDW ) Combining MIDW with MPHC for incremental high quality diesel Case study 2

3 EMRE Technologies for Quality Fuels EMRE HYDROFINING Naphtha Distillate Waxy Feeds Heavy Feeds FCC Naphtha ULSD MPHC GO-fining SCANfining OCTGAIN SM Hydrofining ULSD + MAXSAT ULSD + HDHDC MDDW 3 MIDW LCO Upgrading MPHC + MIDW Residfining

4 Processing Options for Clean Distillate Fuels Ultra Low Sulfur HDS Dewaxing Dearomatization Processing LCO and other Tough Feeds MPHC for Plus Production Optimum Depends Upon Desired Diesel Quantity and Quality 4

5 MPHC - Typical Operations Range of Conditions Conversion Pressure LHSV Recycle Gas WABT Operating Cycle Utilities per 1000 BPSD * Electric Power Fuel (abs duty) MP Steam BFW Cooling Water Lean Amine Wash Water %wt. barg v/v-hr Nm 3 /m 3 o C months kw kw kg/hr m 3 /hr m 3 /hr m 3 /hr m 3 /hr (350) *Note: Middle East VGO Feed 5

6 Typical MPHC Performance Conversion H 2 Pressure %wt. bar H 2 Consumption Nm3/m Kerosene Properties Sulfur Smoke Pt. Diesel Properties Sulfur Cetane No. Aromatics Poly-Aromatics wppm mm wppm %wt. %wt < Note: Middle East VGO Feedstock 6

7 MPHC Process Flow Diagram Typical hydroprocessing flow sheet Reactor design and internals important Post treating unit or MIDW reactor to improve quality / conversion Reactor Recycle Fractionator Compressor Gasoline Lean Amine Naphtha Low Temp. Separator Off-Gas Rich Amine Kerosene Diesel PTU or MIDW if desired High Temp. Separator Stripper Steam VGO/DAO Hydrogen Feed Steam 7 Waxy Basestocks or FCC Feed

8 High vs. Moderate Pressure Unit MPHC HPHC Conversion, % Pressure, barg Installed Cost, US$ Base Base + 20 Diesel Properties Sulfur Cetane Index p- Aromatics < < <1 Hydrogen Demand Base Base x 1.4 8

9 MPHC with Integrated Diesel Treating Design (1) HYDROGEN FEED MPHC Integrated ULSD Distillate Treater DISTILLATES HAGO VGO HVGO LCO HCGO LCGO DAO Integrated Product Recovery Section JET FUEL PREMIUM DIESEL VLS FCC FEED (1) Danzinger at al. ERTC

10 MPHC With PTU Integrated SPIDER VORTEX REACTOR MAKE-UP COMPRESSOR HYDROGEN HEATER RECYCLE COMPRESSOR WATER WASH LEAN AMINE ABSORBER PTU REACTOR PTU PREHEAT LOW TEMP SEPARATOR RICH AMINE VGO FEED HIGH TEMP SEPARATOR SOUR WATER FUEL GAS STEAM CHARGE PUMP PRODUCT STRIPPER WILD NAPHTHA HIGH AROMATICS DIESEL FROM STEAM FRACTIONATOR High Quality DIESEL PRODUCT FRACTIONATOR 10

11 Cetane Number Diesel Composition Strongly Effects Cetane Long branched single rings best for cetane N- Parrafins have good cetane but poor cold flow properties LCO composition limits cetane improvement + Aromatics saturation provides some improvement low 40 s Effect of Composition on cetane Number + Hydrocracking and ring opening required 100 n-paraffins 80 Cyclohexanes Benzenes Decalins 20 Teralins SRGO LCO 0 Naphthalene s Arosat MPHC Molecular Weight MPHC and MIDW Excellent Technology Choices 11

12 Cetane and Gravity Improvement vs. Aromatic Saturation 10 3 Cetane No. Increase API Gravity Increase Aromatics Removed, wt% Aromatics Removed, wt% 12

13 Diesel Cetane Improvement - Hydrocracking Feed Cetane Index = 52 Pressure = 600 psig Pressure = 1000 psig Cetane Index Cetane Index Temperature, F HDT only HDHDC Temperature, F HDT only HDHDC 13

14 MIDW - A Novel Dewaxing Process Mobil Isomerization Dewaxing Isomerizes waxy n-paraffins in gas oils Proprietary ExxonMobil family of catalysts Low pressure fixed-bed process Commercially proven 14

15 ExxonMobil Diesel Dewaxing Technology Diesel selectivity controlled by zeolite type, formulation and conditions F+ (150C+) Yield, wt% MDDW (ZSM-5) Operating Line MIDW Operating Range Cloud Point Reduction, Deg F 15

16 Technology for Producing Winter Diesel Reduce sulfur and convert paraffins to improve cold flow properties Maintain or improve cetane with high yields of quality diesel fuel Feeds Virgin & cracked 0.2 to 2.0 % S CI MULTI-BED SPIDER-VORTEX REACTORS Rxr -1 Process Conditions + 1 or 2 stage reactors + Conv. or MIDW catalysts + Long cycle lengths + Low H 2 consumption Rxr -2 (optional ) RECYCLE COMPRESSOR LTS Diesel Product < 10 wppm S Cetane improv. +5 Cloud point: 50 o C OFF GAS MAKEUP COMPRESSOR ExxonMobil s MIDW is Leading Technology for Winter Diesel 16 STRIPPER NAPHTHA DEWA XED DIESE L

17 MIDW Reactor Configurations Waxy Feed MIDW Low Pour, High Cetane Diesel Moderate S, N HDT MIDW Lower Reactor Temperatures Low Sulfur Distillates H 2 S, NH 3 High S, N HDT MIDW Lower Reactor Temperatures Higher Distillate Yields VGO Feed MPHC H 2 S, NH 3, Distillates MIDW Premium Quality Distillates Low Pour Point Bottoms Long Catalyst Life 17

18 MPHC/MIDW Integration for High Conversion HYDROGEN FEED MPHC (Stage 1) Stage 1 bottoms MIDW (Stage 2) DISTILLATES HAGO VGO HVGO LCO HCGO LCGO DAO Integrated Product Recovery Section JET FUEL PREMIUM DIESEL VLS FCC FEED 18

19 MIDW Product Inspections Feedstock Naphtha Kerosene Diesel LSHFO Boiling Range, o C C Yield, Vol% Gravity, o API Sulfur,ppm wt 260 < Smoke,mm Freeze, o C - - < Pour Point, o C > <-7 Cetane Index P/N/A, wt% 44/39/17 - -/-/10 45/31/24 36/42/22 19

20 Case Study Goal: achieve high conversion economically Feed: Middle East crude HVGO Configuration: MPHC for stage 1 and MIDW for stage 2 Optimize conversion in each stage High jet yield preferred Estimate yields and qualities 20

21 MPHC/MIDW Reactor Operating Conditions MPHC MIDW Combined Conversion, wt% 55% 55% 80% Feed Rate, % of Fresh Feed Chemical H 2 Consumption Nm 3 /m Reactor Inlet Pressure Barg Minimum Cycle Length Months

22 Yields and Product Qualities (SOR) wt% Bottoms Diesel Jet Yield on Fresh Feed wt% SG Sulfur ppmw <10 <6 <2 Cloud Point o C -18 Freeze Point o C -50 Smoke Point mm 25 Total Aromatics wt% PNA wt% Centane Index, D Centane Index, D Hydrogen Content wt% >14 22

23 Comparison of Options for High Conversion 2 Stage MPHC 1 Stage HPHC 2 Stage MPHC with Recycle Conversion 85% 75-85% >95% Capital Investment Base Base Base +50% Hydrogen Consumption Base Base x 1.2 Base x 1.3 Distillate Yield Base Base 2% Base +6% Reactor Fabrication Rolled Plate Forged Forged Reactor Delivery months months months 23

24 2 Stage Integrated MPHC/MIDW Advantages Better overall yield No extra cracking to lighter products. Better product properties MIDW catalyst in 2 nd stage - better distillate qualities and cold flow properties Unit will make Euro IV diesel spec - density, CI better than HP operations Jet - better smoke point and freeze point Flexible 2 stage design Easy transition between max-diesel or max-jet operation Optimize conversion between two systems Option to process external feeds Lower pressure and no reprocessing hydraulics Lower TIC Lower hydrogen consumption/compression Lower ops cost Improved operability, reliability, and safety Easier and shorter turnaround Favorable project execution Better reactors/compressor delivery 24

25 Conclusions A number of processing and catalyst options available + Optimum choice depends upon specific quality / quantity needed MPHC combined with MIDW allows high pressure performance at low operating cost ExxonMobil has the technology and extensive operating experience + Well positioned to assist customers in meeting their requirements 25