Abstract Process Economics Program Report 211A HYDROCRACKING FOR MIDDLE DISTILLATES (July 2003)

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Abstract Process Economics Program Report 211A HYDROCRACKING FOR MIDDLE DISTILLATES (July 2003) Middle distillate is the collective petroleum distillation fractions boiling above naphtha (about 300 F, 149 C) and below residue oil (700 F+, 371 C+). Middle distillate products are marketed as kerosene, jet fuel, diesel fuel and fuel oils. Worldwide growth in demand for these products to 2012 is forecast to be the largest and the fastest of the petroleum products. Hydrocracking is a petroleum refining process where cracking occurs simultaneously with hydrogenation of the products. Hydrocracking for middle distillates is growing worldwide into a process critical to petroleum refinery profitability. The combination of desulfurized, denitrogenated lighter products of lower overall aromaticity makes hydrocracking an ideal process for producing diesel, jet and gas turbine fuels meeting the more stringent fuel specifications effective starting in 2005. Currently the most common on road diesel fuel sulfur specification is 500 ppm (350 ppm in Europe) with higher limits in some countries. The European Commission adopted a 10 ppm sulfur specification for on road diesel fuel beginning in 2005 with full conversion by 2010. An U.S. EPA rule phases in 15 ppm sulfur highway diesel fuel starting June 1, 2006. In Japan, 10 ppm sulfur fuel in 2008 is proposed. Countries in other regions of the world are also working to reduce the sulfur in diesel fuel. The U.S. EPA recently proposed sulfur in off road diesel fuel be limited to 15 ppm in 2010. Although the proposal does not cover heating oil or jet fuel, a significant amount of these fuels may be desulfurized anyway due to refining and pipeline limitations and economics. In order to meet the on road diesel fuel specifications, the capital investment needed by the refining industry is anticipated to be substantial (estimates range from $3 to 13 billion for the U.S. industry). This report reviews the chemistry, technology and economics of producing middle distillates such as jet fuel and diesel fuel meeting the new near zero sulfur (NZS) specifications slated for 2005 and beyond. A number of improved hydrocracking processes and catalysts are commercially available. Revamping of existing hydrocrackers and the conversion of hydrotreaters to mild (low pressure) hydrocrackers is also reviewed. We evaluate the economics of a generic vacuum gas oil hydrocracker that produces jet fuel and NZS diesel fuel. This report should provide a useful overview of hydrocracking and of middle distillate products and their properties with in-depth review of process developments and economics within the industry. People involved in the energy industry, professionals who research, develop, plan, operate, design plants or manage investments in the petroleum refining industry as well as those in allied industries could benefit from the information contained in this report. PEP 03 RHN

CONTENTS 1 INTRODUCTION... 1-1 2 CONCLUSIONS... 2-1 3 SUMMARY... 3-1 COMMERCIAL ASPECTS... 3-2 TECHNICAL ASPECTS... 3-3 ECONOMIC ASPECTS... 3-4 4 INDUSTRY STATUS... 4-1 HYDROCRACKING ROLE... 4-4 DIESEL ENGINE TECHNOLOGY... 4-6 MARKET SHARE... 4-7 SUPPLY AND DEMAND... 4-10 INSTALLED HYDROCRACKING CAPACITY... 4-16 NEW CONSTRUCTION... 4-28 5 GENERAL PROCESS REVIEW... 5-1 MIDDLE DISTILLATE PRODUCTS AND SPECIFICATIONS... 5-4 Heavy Naphtha... 5-5 Kerosene... 5-5 Gas Turbine Fuel (Jet Fuel)... 5-5 Diesel Fuel... 5-12 Fuel Oil... 5-15 MECHANISM AND KINETICS... 5-18 Mechanisms... 5-21 H Activation... 5-23 Paraffins... 5-25 Naphthenes... 5-28 iii

CONTENTS (Continued) Aromatics... 5-29 Kinetics... 5-31 Fouling Mechanisms... 5-33 CATALYSIS... 5-33 Hydrogenation Component... 5-33 Acid Component... 5-34 Pore Structure... 5-38 Other Catalysts... 5-41 Commercial Catalysts... 5-42 Catalyst Life Cycle... 5-44 Presulfiding... 5-45 Regeneration... 5-47 Catalyst Disposal... 5-48 HYDROCRACKING PROCESSES... 6-3 Types of Hydrocrackers... 6-3 Two-Stage... 6-3 6 HYDROCRACKING PROCESSES... 6-1 PRETREATMENT FOR HYDROCRACKING... 6-2 Single Stage... 6-6 Reactors... 6-7 Integrated Processes... 6-12 FRIPP/Sinopec Process... 6-12 Sud-Chemie Processes... 6-13 Mild Hydrocracking Processes... 6-14 Chevron Lummus Global (Optimized Partial Conversion)... 6-16 Haldor Topsoe (Topsoe Mild Hydrocracking/VGO Hydrotreating Process)... 6-17 IFP (Hytail)... 6-17 MAKfining (Moderate Pressure Hydrocracking)... 6-18 iv

CONTENTS (Continued) Technip/RIPP/Sinopec (MHUG Process)... 6-19 UOP LLC (Advanced Partial Conversion Unicracking)... 6-21 VGO and Lighter Feed Processes... 6-24 Axens... 6-24 VGO Hydrocracking... 6-24 T-Star sm Process... 6-24 Chevron Lummus Global LLC (Isocracking)... 6-25 Lurgi... 6-26 Shell Global Solutions International B.V... 6-26 UOP LLC (Hycycle Unicracking)... 6-27 Residual Feedstock Processes... 6-28 Axens/IFP (H-Oil)... 6-28 Chevron Lummus Global LLC (LC-Fining)... 6-29 ENI - Snamprogetti (ENI Slurry Technology... 6-30 Hydrocarbon Technologies, Inc. (HTI Resid-cat Process)... 6-31 Petro-Canada (Canmet)... 6-32 SNC-Lavalin, Inc. (U-Can)... 6-32 Veba (Vebi-Comb-Cracking)... 6-32 REVAMPS... 6-32 Increased Capacity... 6-32 Revamping for Near Zero Sulfur Diesel... 6-33 Single-Stage Unit... 6-34 Hydrotreater to Mild Hydrocracker... 6-34 Two-Stage Units... 6-35 Naphtha to Middle Distillate Product Slate... 6-36 PROCESS FACTORS... 6-36 Feedstock Effects... 6-36 Process Configuration Effects... 6-40 Operating Conditions... 6-40 v

CONTENTS (Continued) Temperature... 6-41 Hydrogen Partial Pressure... 6-42 Ammonia Partial Pressure... 6-44 Space Velocity... 6-44 DESIGN CONSIDERATIONS... 6-44 Mercaptan Recombination... 6-44 Reactors... 6-44 Reactor Internals... 6-45 Pressure Drop... 6-46 Corrosion... 6-46 Ammonium Bisulfide Corrosion... 6-46 H 2 S and Sulfur Corrosion... 6-47 Naphthenic Acid Corrosion... 6-47 Stress Corrosion... 6-48 Heat Integration... 6-48 Separations... 6-48 Analysis and Control... 6-50 7 ECONOMICS... 7-1 PROCESS DESCRIPTION... 7-1 Reaction - Section 100... 7-21 Product Recovery & Purification - Section 200... 7-21 PROCESS DISCUSSION... 7-22 Feedstock... 7-22 Product Yields and Quality... 7-22 Reaction -- Section 100... 7-22 Product Recovery & Purification - Section 200... 7-23 Hydrogen Systems... 7-23 Materials of Construction... 7-24 vi

CONTENTS (Concluded) Waste Treatment and Disposal... 7-24 COST ESTIMATES... 7-24 Capital Costs... 7-24 Production Costs... 7-25 Profitability... 7-26 APPENDIX A: PATENT SUMMARY TABLES... A-1 APPENDIX B: DESIGN AND COST BASES... B-1 APPENDIX C: CITED REFERENCES... C-1 APPENDIX D: PATENT REFERENCES BY COMPANY... D-1 APPENDIX E: PROCESS FLOW DIAGRAM... E-1 vii

ILLUSTRATIONS 4.1 Hydrocracking in the Fuels Refinery... 4-5 4.2 Regional Market Share of Middle Distillate... 4-8 4.3 Worldwide Petroleum Products Market Share... 4-8 4.4 U.S. Middle Distillates Production, 1983-2002... 4-11 4.5 Historical U.S. Prices of Middle Distillate Products and Crude Oil... 4-14 4.6 Relationships Between U.S. Prices of Middle Distillates and Crude Oil... 4-15 4.7 U.S. Petroleum Administration for Defense Districts... 4-18 5.1 Hydrogen Content and Molecular Weight Relationship Between Feedstocks and Products... 5-1 5.2 Representative Mono-and Polyaromatics... 5-2 5.3 Proposed Mechanism for Elemental Sulfur Initiation of Free Radicals... 5-18 5.4 Catalytic Hydrocracking Reaction Network... 5-19 5.5 Typical N-Paraffin Hydrocracking Reation Pathway... 5-26 5.6 Beta Scission and Ismerization Mechanisms... 5-27 5.7 Mechanism of Direct Naphthene Ring Opening Via Nonclassical Carbonium Ion Mechanism... 5-28 5.8 Classical Mechanism of Central Naphthene Ring Opening... 5-29 5.9 Molecular Carbon Number Distributions in Hydrocracking and FCC of N- Hexadecane at about 50% Conversion... 5-35 6.1 Simplified Two-Stage Hydrocracking Process... 6-4 6.2 Simplified Two-Stage Process with Separate Recycle H 2... 6-5 6.3 Hycycle Unicracking Process... 6-6 6.4 Mild Hydrocracker Flow Diagram... E-3 6.5 High Pressure Hydrocracker Flow Diagram... E-5 6.6 Mild Hydrocracking Process... 6-14 6.7 UOP's Advanced Partial Conversion Unicracking Process... 6-23 6.8 Relationship of Diesel Fuel Yield to Jet Fuel Yield... 6-49 viii

TABLES 3.1 Summary of Cost Estimates for a Middle Distillate Hydrocracker... 3-5 4.1 Trend in European Diesel Fuel Specifications... 4-2 4.2 Hydrocracking Compared to Catalytic Cracking a... 4-6 4.3 Worldwide Petroleum Product Market Share... 4-9 4.4 U.S. and World Demand Forecast for Petroleum Products... 4-12 4.5 European Middle Distillate Demand and Market Share... 4-13 4.6 Growth in Hydrocracking (1988-2003)... 4-16 4.7 Growth in Hydrocracking for Fuels in the U.S. (1993-2003)... 4-16 4.8 Summary of North American Fuel Hydrocracking Refineries Capacities... 4-17 4.9 North American Fuel Hydrocracking Refineries Capacities... 4-19 4.10 Summary of Capacities of World Fuel Hydrocracking Refineries... 4-22 4.11 Capacities of World Fuel Hydrocracking Refineries Outside North America... 4-23 4.12 Hydrocracking Refineries - Distribution of Hydrocracking Capacities a... 4-28 4.13 Announced Hydrocracker Construction... 4-29 5.1 Middle Distillate and Heavy Oil Products and Uses... 5-3 5.2 Representative Compound Classes in Middle Distillate Fuel... 5-4 5.3 Kerosene Specifications... 5-6 5.4 Jet Fuel Grades and Specifications... 5-7 5.5 Gas Turbine Fuel Specifications... 5-9 5.6 Polar Organic Compounds Desorbed from Spent Clays Treating Jet Fuels... 5-10 5.7 Typical Speed Ranges of Three Types of Diesel Engines... 5-12 5.8 General ASTM D-975 Specifications for Three Diesel Fuel Grades... 5-13 5.9 Properties of Diesel Fuels... 5-15 5.10 Fuel Oil Specifications... 5-17 5.11 Heat of Reaction... 5-20 5.12 Bond Dissoctiation Energies... 5-20 5.13 Products of Hydrocracking Representative C 10 Hydrocarbon Types... 5-22 ix

TABLES (Continued) 5.14 Zeolite-Amorphous and All Amorphous Catalysts Comparison... 5-37 5.15 Catalyst Effect on Diesel Fuel Aromatic Content... 5-37 5.16 Product Distributions with MCM-41, Silica-Alumina andusy Catalyst Supports a 5-39 5.17 Characterization of an Extruded Iron-Active Carbon Hydrocracking Catalyst... 5-41 5.18 Selected Hydrocracking Catalyst Supplies... 5-43 5.19 Chemical Composition and Selected Physical Properties of Commercial Catalyst... 5-44 5.20 Sulfiding Reactions... 5-45 6.1 Technology and Scope Considerations... 6-2 6.2 Main Features of Residue Hydrocracking Reactors... 6-8 6.3 Hydrocracking Safaniya Vacuum Residue by Various Types of Processes... 6-9 6.4 Optimizing First Stage Catalyst System Benefits... 6-10 6.5 Selected Integrated Hydroprocess Combinations for Diesel Fuel... 6-13 6.6 Mild Hydrocracking Process Conditions Compared to Concentional Conditions. 6-15 6.7 Process Variable in Milk Hydrocracking... 6-16 6.8 Hytail Process Compared to High Pressure Hydrocracking... 6-18 6.9 Product Distribution of MHUG Unit Cracking 50% Light VGO and 50% LCO... 6-20 6.10 Yields from Mild Hydrocracking of Heavy Diesel Fuel by MHUG Process... 6-21 6.11 Partial Conversion Unicracking Process Compared to Mild Hydrocracking... 6-22 6-12 Relative Revamp Costs... 6-34 6.13 Polynuclear Aromatics in Desulfurized Residue VGO at Start and End of Run... 6-38 6.14 Effect of Heavy PNA Removal by Adsorption Compared to Removal by Purging 6-38 6.15 Feedstock Effects on Diesel Fuel Quality in Single Stage Hydrocracking... 6-39 6.16 Operating Conditions for Diesel and Jet Fuel Mode of a Single Stage Hydrocracker... 6-40 6.17 Process Flexibility in Single Stage Hydrocracker - Effect of Temperature... 6-41 6.18 Effect of Pressure on Yield and Quality of Jet Fuel and Diesel Fuel... 6-42 6.19 Effect of H 2 Partial Pressure on Stage One Hydrotreated Product Quality... 6-43 x

TABLES (Continued) 6.20 Effect of H 2 Partial Pressure on Second Stage Hydrocracked Product Aromatics...6-43 7.1 Design Bases and Assumptions - Mild Hydrocracker... 7-3 7.2 Design Bases and Assumptions - High Pressure Hydrocracker... 7-4 7.3 VGO Feedstock Characterization... 7-5 7.4 Overall Reactors Yields (Second Reactor Effluent)... 7-5 7.5 Product Characterizations (Assumed, Both Processes)... 7-6 7.6 Mild Hydrocracker for Middle Distillates Stream Flows... 7-7 7.7 High Pressure Hydrocracker for Middle Distillates Stream Flows... 7-11 7.8 Mild Hydrocracker for Middle Distillates Major Equipment... 7-15 7.9 HP Hydrocracker for Middle Distillates Major Equipment... 7-17 7.10 Mild Hydrocracker for Middle Distillates Utilities Summary... 7-19 7.11 HP Hydrocracker for Middle Distillates Utilities Summary... 7-20 7.12 Mild Hydrocracker for Middle Distillates Total Capital Investment... 7-27 7.13 Mild Hydrocracker for Middle Distillates Direct Costs by Section, $ thousands/yr... 7-28 7.14 HP Hydrocracker for Middle Distillates Total Capital Investment... 7-29 7.15 HP Hydrocracker for Middle Distillates Direct Costs by Section, $ thousands/yr... 7-30 7.16 Mild Hydrocracker for Middle Distillates Production Costs... 7-31 7.17 HP Hydrocracker for Middle Distillates Production Costs... 7-33 7.18 ROI Sensitivity to FCC Feedstock Product Value... 7-35 xi

TABLES (Concluded) A.1 Hydrocracking for Middle Distillates -- Process Patents Patent Summary... A-3 A.2 Hydrocracking for Middle Distillates -- Catalyst Patents Patent Summary... A-20 xii