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Assessment of Criteria Pollutant Emissions from Liquid Fuels Derived from Natural Gas - 2002

Alleman, Teresa L.
McCormick, Robert L.
Vertin, Keith

National Renewable Energy Laboratory

In this pdf format, this document has 46 pages and is 271kb.

Table of Contents

EXECUTIVE SUMMARY i
  Key Conclusions i
ABBREVIATIONS AND ACRONYMS iii
UNITS OF MEASURE iv
TABLE OF CONTENTS v
LIST OF TABLES vi
INTRODUCTION 1
STATUS OF FISCHER-TROPSCH and HIGH QUALITY DIESEL FUELS 1
  GTL and Fischer-Tropsch Fuel Properties 1
Fuel Property Effects on Diesel Exhaust Emissions 7
  Sulfur Content 7
Cetane Number 8
Aromatic Content 9
Density 9
Distillation Temperature 10
Inclusion of Oxygenates 10
  Emissions Performance of F-T and F-T Like Diesel Fuels 11
  Exhaust Emissions Effects on Current Technology Engines and Vehicles 11
Emissions Reductions in Future Engines 15
Statistical Significance of Reported Emissions Reductions 17
Overall Statistical Significance of the Literature Data 19
  Durability/Materials Compatibility 19
Emissions Durability/Engine Durability 19
Fuel Economy 20
 
FUEL PROPERTY REQUIREMENTS TO ENSURE ENVIRONMENTAL BENEFITS 21
 
APPENDIX A - DISCUSSION OF F-T AND F-T/ COD DIESEL PETITIONS 23
  Syntroleum Petition 24
Mossgas Petition 28
Rentech Petition 31
Conclusions 33
APPENDIX B - DISCUSSION OF STATISTICAL ANALYSIS TECHNIQUES 34
  Two Sample t-test Analysis - Approach 34
Usefulness of the Two Sample t-test 34
Assumptions of the Two Sample t-test 34
Example of two Sample t-test 34
Wilcoxon Signed-Rank Test 34
Usefulness of Wilcoxon Signed-Rank Test 35
Example of Wilcoxon Signed-Rank Test 35
REFERENCES 37
 
LIST OF TABLES
Table 1 ASTM D975 No. 2 Low Sulfur Diesel property requirements 2
Table 2 Properties of Fischer-Tropsch, GTL, and conventional diesel fuels 3-6
Table 3 Heavy-duty engine dynamometer hot start FTP emission results for F-T diesel fuel compared to conventional diesel fuel 12
Table 4 Heavy-duty engine dynamometer FTP emission results for F-T diesel fuel relative to No. 2 diesel fuel baseline. The values are percentages of the No. 2 baseline emissions 12
Table 5 Heavy-duty engine dynamometer steady state emission results, composite of all modes 12
Table 6 Heavy-duty engine dynamometer steady state emission results, mode-by-mode emissions 13
Table 7 Heavy-duty chassis dynamometer emission test results 14
Table 8 Heavy-duty engine dynamometer steady state emission results, off-highway engine, mode-by-mode emissions 15
Table 9 Light-duty steady state emission test results 15
Table 10 Light- and heavy-duty emission test results for as-is and optimized configuration for a Ford Power Stroke 7.3L diesel engine 17
Table 11 Engine out and catalyst out NOx emissions for a DeNOx catalyst for a Ford 2000 Power Stroke 7.3L diesel engine 17
Table 12 P-value for emissions reductions reported in literature comparing F-T and GTL diesel fuels to conventional diesel fuel 18
Table 13 Critical Value and Statistical Significance of Emission Reduction with F-T Diesel Fuel compared to Conventional Diesel Fuel, All Reported Literature Values 19
Table 14 Importatn fuel properties for F-T diesel fuels 21
Table 15 Typical "S-2" fuel properties, provided by Syntroleum in petition to DOE 24
Table 16 Results of light- and heavy-duty FTP testing with S-2 compared to current emissions standards 25
Table 17 Results of engine dynamometer FTP testing on 1999 Cummins 5.9L B engine 25
Table 18 Light heavy-duty test results for a 2000 Dodge Ram 2500HD with a Cummins B engine 26
Table 19 Light-duty test results for a 1999 Volkswagen Golf GL TDI 26
Table 20 Comparison of Syntroleum test fuel with conventional diesel fuel for toxic and N2O emissions 27
Table 21 P-values for Syntroleum supplied diesel fuel compared to CARB diesel, No. 2 diesel and Swedish City 1 diesel fuel 28
Table 22 Composition of Mossgas RFD1, RFD2, and RFD3 fuels 29
Table 23 Typical fuel properties for Mossgas RFD1, RFD2, and RFD3 fuels, provided by Mossgas in petition to DOE 29
Table 24 Heavy-duty engine dynamometer FTP emissions using Mossgas F-T and GTL fuels 30
Table 25 Chassis dynamometer emissions on transit buses fueled with Mossgas fuel 30
Table 26 Statistical significance of emissions reductions for Mossgas fuels (p-value), compared to conventional No. 2 diesel fuel for engine testing only 31
Table 27 Typical Rentech product analysis and recommended Fischer-Tropsch diesel fuel standards, provided by Rentech in petition to DOE 32
Table 28 Emissions Reductions with Rentech Diesel Fuel 32
Table 29 Paired NOx data from Table 3 for demonstration of Wilcoxon Signed-Rank Test 35
Table 30 Calculation of the difference of the paired NOx data and the absolute value of the difference for the Wilcoxon Signed-Rank Test 35
Table 31 Rank and signed rank of the difference of the NOx data taken from Table 3 36