Disclaimer

i

Acknowledgement

ii

Abstract

iii

List of Tables

vii

List of Figures

ix

Executive Summary

xiv

1.

Chapter 1:  Introduction

1

1.1

Background

1

1.2

This Project

2

2.

Chapter 2:  Literature Search and Thermodynamics Analysis

4

2.1

Reaction Concepts

4

2.1.1

Reaction with SO₂

4

2.1.2

Partial Oxidation

4

2.1.3

Reaction with H₂O

5

2.1.4

Summary

5

2.2

Thermodynamic Analysis

6

2.2.1

Reduction-Sulfidation Analysis

7

2.2.2

Regeneration Analysis

9

2.2.2.1

Reaction with SO₂

9

2.2.2.2

Partial Oxidation

13

2.2.2.3

Reaction with Steam

15

2.2.3

Conclusions

15

3.

Chapter 3:  Experimental Apparatus

18

3.1

Electroturbulance Reactor

18

3.2

Fixed-Bed Reactor (FeS Regeneration)

19

3.3

Fixed-Bed Reactor (Cerium Sorbent Studies)

21

4.

Chapter 4:  FeS Partial Oxidation Regeneration Studies

24

4.1

FeS Properties

24

4.2

Electrobalance Test Results

24

4.3

Fixed-Bed Reactor Test Results

30

4.4

Interpretation of the Fixed-Bed Results

36

5.

Chapter 5:  Cerium Oxysulfide Regeneration

39

5.1

Cerium Oxide from Rhone-Poulene

39

5.2

CeO₂ Sulfidation

40

5.3

Ce₂OS Regeneration

43

5.3.1

The Effect of Temperature

43

5.3.2

The Effect of SO₂ Concentration

44

5.3.3

The Effect of Volumetric Feed Rate

45

5.3.4

The Effect of Pressure

48

5.3.5

The Effect of Residence Time

49

5.4

Conclusions

49

6.

Chapter 6:  Reduction and Sulfidation of Cerium Oxide

51

6.1

Reduction of CeO₂ to CeOn (N<2)

51

6.2

Sulfidation of CeOn (N<2) to Ce₂O₂S

55

6.2.1

The Effect of Temperature

57

6.2.2

The Effect of H₂S Concentration

57

6.2.3

The Effect of Volumetric Geed Rate

60

6.2.4

The Effect of Pressure

62

6.2.5

Comparison of Results With and Without Pre-Reduction

62

6.2.6

The Effect of Steam in Feed Gas

64

6.3

Conclusions

63

7.

Chapter 7:  Multicycle Test Results

68

7.1

Test Ce-116 (Cycles 01 through 10)

68

7.2

Test Ce-204 (Cycles 01 through 25)

71

7.3

Conclusions

76

8.

Chapter 8:  Results Using Other CeO₂ Sources

78

8.1

Results from Test Ce-123 Using MC Sorbent

78

8.2

Sulfidation Test Results Using Other CeO2 Sorbents

82

8.3

Conclusions

87

9.

Process Analysis

88

9.1

Two-Stage Desulfurization Using Cerium Sorbent with So₂ Regeneration

88

9.2

Single-Stage Desulfurization Using Zinc Sorbent With DSRP

90

9.3

Design Basis

90

9.4

Material and Energy Balance Results

94

9.5

Process Design

96

9.6

Capital Cost Estimates

97

9.7

Operating Cost Estimates

102

9.8

Levelized Cost

104

9.9

Cost Sensitivity Analysis

107

9.10

Conclusions

110

10.

References

112