mixed alcohol, diesel and syngas synthesis from forest - SMARTech

178 Pages·2008·1.26 MB·English

by  David Koch

MIXED ALCOHOL, DIESEL AND SYNGAS SYNTHESIS FROM
FOREST RESIDUES VIA GASIFICATION – AN ECONOMIC
ANALYSIS

A Thesis
Presented to
The Academic Faculty

by

David Koch

In Partial Fulfillment
of the Requirements for the Degree
Master of Science in Chemical Engineering in the
School of Chemical Engineering

Georgia Institute of Technology
November, 2008
MIXED ALCOHOL, DIESEL AND SYNGAS SYNTHESIS FROM
FOREST RESIDUES VIA GASIFICATION – AN ECONOMIC
ANALYSIS

Approved by:

Dr. Matthew J. Realff, Advisor
School of Chemical Engineering
Georgia Institute of Technology

Dr. John D. Muzzy
School of Chemical Engineering
Georgia Institute of Technology

Dr. Carsten Sievers
School of Chemical Engineering
Georgia Institute of Technology

Dr. Nikolai DeMartini
Institute of Paper Science and Technology
Georgia Institute of Technology

Date Approved: November 25th, 2008
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ACKNOWLEDGEMENTS

I would like to thank Dr. Realff for his guidance, patience and help during this project. I
would also like to thank Dr. Iisa and Dr. Frederick for giving me the opportunity to work
on this project.
My thanks go also to my committee members Dr. Muzzy, Dr. Sievers and Dr. DeMartini.

Special thanks to James Stokes for valuable discussions about Aspen input errors,
convergence errors and all the other strange errors I encountered during my work on this
project.

I would also like to thank my family and friends, both here in the US and in Europe, for
being so patient and supportive.
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LIST OF ACRONYMS

ASF Anderson-Schulz-Flory
BCL Battelle Columbus Laboratory
BTL Biomass to Liquid
CW Cooling Water
DB Declining Balance
DOE Department of Energy
EIA Energy Information Administration
FT Fischer-Tropsch
FTS Fischer-Tropsch Synthesis
GAL Gallon
GPM Gallons per Minute
IRR Internal Rate of Return
MACRS Modified Accelerated Cost Recovery System
MDSP Minimum Diesel Selling Price
MESP Minimum Ethanol Selling Price
MM Million
MPSP Minimum Product Selling Price
MSSP Minimum Syngas Selling Price
MTBE Methyl-Tert-Butyl Ether
NREL Nation Renewable Energy Laboratory
ODT Oven Dry Ton
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PFD Process Flow Diagram
PPB Parts per Billion
PPM Parts per Million
TPI Total Project Investment
WGS Water Gas Shift
WWT Waste Water Treatment
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TABLE OF CONTENTS

ACKNOWLEDGEMENTS ............................................................................................... iii

LIST OF ACRONYMS ..................................................................................................... iv

LIST OF TABLES ............................................................................................................. ix

LIST OF FIGURES .......................................................................................................... xii

SUMMARY ...................................................................................................................... xv

CHAPTER 1: INTRODUCTION ....................................................................................... 1

CHAPTER 2: LITERATURE REVIEW ............................................................................ 6

2.1 Gasifiers .................................................................................................................... 6
2.2 Fischer-Tropsch Reactors ......................................................................................... 7
2.3 Fischer-Tropsch (FT) Conditions ............................................................................. 9
2.4 Fischer-Tropsch Catalysts ......................................................................................... 9
2.5 Process Simulation .................................................................................................. 11

CHAPTER 3: SYNGAS PRODUCTION ........................................................................ 12

3.1 Introduction ............................................................................................................. 12
3.2 Plant Sizes ............................................................................................................... 13
3.3 Feedstock Composition ........................................................................................... 14
3.4 Syngas Production Process ..................................................................................... 16
3.4.1 Process overview ............................................................................................. 16
3.4.2 Feed Preparation (A100 and A100DRYR) ...................................................... 19
3.4.3 Gasification (A200) ......................................................................................... 19
3.4.4 Gas Cleanup and Conditioning (A300)............................................................ 22
3.5 Results Syngas Production ...................................................................................... 26
3.5.1 Best Case and Worst Case ............................................................................... 27
3.5.2 Economics ........................................................................................................ 28
3.5.3 Sensitivities ...................................................................................................... 32

CHAPTER 4: MIXED ALCOHOLS PRODUCTION ..................................................... 40

4.1 Introduction ............................................................................................................. 40
4.2 Plant Sizes ............................................................................................................... 41
4.3 Feedstock Composition ........................................................................................... 42
4.4 Mixed Alcohol Production Process ........................................................................ 43
4.4.1 Process overview ............................................................................................. 43
4.4.2 Mixed Alcohols Synthesis (A400) ................................................................... 45
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4.4.3 Alcohol Separation (A500) .............................................................................. 48
4.4.4 Steam, Cooling Water and Power (A600, A700 and A900) ............................ 48
4.5 Results Mixed Alcohol Production ......................................................................... 49
4.5.1 Economics ........................................................................................................ 49
4.5.2 Sensitivities ...................................................................................................... 55

CHAPTER 5: FT DIESEL PRODUCTION ..................................................................... 61

5.1 Introduction ............................................................................................................. 61
5.2 Plant Sizes ............................................................................................................... 62
5.3 Feedstock Composition ........................................................................................... 63
5.4 Diesel Production Process ....................................................................................... 64
5.4.1 Process overview ............................................................................................. 64
5.4.2 Fischer-Tropsch Diesel Synthesis (A400) ....................................................... 66
5.4.3 Recycling versus Combustion .......................................................................... 71
5.4 Results FT Diesel Production ................................................................................. 73
5.4.1 Economics ........................................................................................................ 73
5.4.2 Sensitivities ...................................................................................................... 79

CHAPTER 6: INTEGRATION WITH KRAFT MILL .................................................... 85

6.1 Background Information ......................................................................................... 85
6.2 Process .................................................................................................................... 86
6.3 Assumptions and Calculations ................................................................................ 88
6.4 Results Integrated Fuel Plant .................................................................................. 89

CHAPTER 7: ADDITIONAL CASE STUDIES .............................................................. 92

CHAPTER 8: CONCLUSIONS AND RECOMMENDATIONS .................................... 94

8.1 Syngas ..................................................................................................................... 94
8.2 Mixed Alcohols ....................................................................................................... 94
8.3 FT Diesel ................................................................................................................. 94
8.4 Integrated Kraft Mill/Biorefinery ........................................................................... 95
7.5 Future Work ............................................................................................................ 95

REFERENCES ................................................................................................................. 97

APPENDIX A: FLOW DIAGRAMS AND MASS FLOWS SYNGAS STUDY ............ 99

APPENDIX B: FLOW DIAGRAMS AND MASS FLOWS MIXED ALCOHOLS
STUDY ........................................................................................................................... 119

APPENDIX C: FLOW DIAGRAMS AND MASS FLOWS FT DIESEL STUDY ...... 138

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APPENDIX D: SYNGAS COMPOSITION FOR DIFFERENT P, T AND H /CO
2
RATIOS .......................................................................................................................... 146

APPENDIX E: EQUIPMENT LIST SYNGAS STUDY ............................................... 150

APPENDIX F: EQUIPMENT LIST MIXED ALCOHOLS STUDY ............................ 153

APPENDIX G: EQUIPMENT LIST FT DIESEL STUDY ........................................... 158
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LIST OF TABLES

Table 2.4.1: Relative Costs for FT catalysts…………..…………………………………10
Table 2.4.2: Fischer-Tropsch Hydrocarbon Isomers……….……………………………11
Table 3.2.1: Feedstock………………...…………………………………………………13
Table 3.3.1: Weight Composition Feedstock…………………………………………….14
Table 3.3.2: Ultimate Analysis of Southern Pine Residues……………………...………15
Table 3.3.3: Proximate Analysis of Southern Pine Residues…………………………….15
Table 3.3.4: Resulting Ultimate Analysis Feedstock…………………………………….16
Table 3.3.5: Resulting Proximate Analysis Feedstock…………………………………..16
Table 3.4.3.1: Operating Conditions Gasifier and Char Combustor……………………..20
Table 3.4.3.2: Syngas Composition after Gasifier……………………………………….21
Table 3.4.4.1: Current and Target Design Performance of Tar Reformer……………….22
Table 3.4.4.2: Syngas Composition after Tar Reformer…………………………………23
Table 3.4.4.3: Final Syngas Composition………………………………………………..25
Table 3.5.1.1: ΔMSSP for varying moisture contents…………………………………...27
Table 3.5.2.1: Raw Material Consumption and Co-Product Production………………...29
Table 3.5.2.2: Variable Operating Costs Raw Materials………………………………...30
Table 3.5.2.3: Summary Economics Base Case…………………………………………32
Table 4.2.1: Feedstock…………………………………………………………………...41
Table 4.3.1: Resulting Ultimate Analysis Feedstock…………………………………….42
Table 4.3.2: Resulting Proximate Analysis Feedstock………………………………..…42
Table 4.4.2.1: Mixed Alcohols Catalyst Performance Results…………………………..46
Table 4.4.4.2: Syngas Composition Entering Mixed Alcohol Reactor………………..…47
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Table 4.5.1.1: Raw Material Consumption and Co-Product Production………………...51
Table 4.5.1.2: Variable Operating Costs Raw Materials………………………………...52
Table 4.5.1.3: Summary Economics Base Case…………………………………………54
Table 5.2.1: Feedstock…………………………………………………………………...63
Table 5.3.1: Resulting Ultimate Analysis Feedstock…………………………………….63
Table 5.3.2: Resulting Proximate Analysis Feedstock…………………………………..63
Table 5.4.2.1: Syngas Composition Entering Fischer Tropsch Reactor…………………69
Table 5.4.2.2: Product distribution………………………………………………………70
Table 5.4.3.1: Recycling versus Combustion for base case……………………………...71
Table 5.4.1.1: Raw Material Consumption and Co-Product Production………………...75
Table 5.4.1.2: Variable Operating Costs Raw Materials………………………………...76
Table 5.4.1.3: Summary Economics Base Case…………………………………………78
Table 5.4.1.4: Scaling Exponents………………………………………………………..84
Table 6.2.1: Weight Composition Feedstock……………………………………………87
Table 6.2.2: Feedstock Costs…………………………………………………………….87
Table 6.2.3: Steam Production…………………………………………………………...88
Table 6.3.1: Reduced Minimum Selling Price in $/MMBTU…………………………...89
Table 6.4.1: MPSP Integrated and Standalone Plant…………………………………….90
Table A.1: Mass Flows General Process Areas…………………………...……………101
Table A.2: Mass Flows A100DRYR…………………………………………………...104
Table A.3: Mass Flows Area 200 – Gasification……………………………………….106
Table A.4: Mass Flows Area A200CC – Char Combustion……………………………109
Table A.5: Mass Flows A300 – Conditioning………………………………………….112
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