Acknowledgment .............................................. XI
Preface ................................................... XIII
1 Classification of Explosives ................................. 1
1.1 Initiation Sensitivity .................................. 1
1.2 Size .................................................... 1
1.3 Usage ................................................... 2
1.4 Physical Form ........................................... 2
2 Explosive Science ............................................ 5
2.1 Introduction ............................................ 5
2.1.1 Low Explosives ................................... 5
2.1.2 High Explosives .................................. 5
2.2 Initiation and Detonation ............................... 6
2.2.1 Mechanism ........................................ 6
2.3 Propagation and Detonation .............................. 7
2.3.1 Propagation ...................................... 7
2.3.2 Detonation ....................................... 8
2.3.2.1 Ideal/Nonideal Detonation/Critical
Diameter/Ideal Diameter ................. 9
2.3.2.2 Detonation Pressure and Velocity ........ 9
2.4 Reaction Chemistry in Explosives ....................... 11
2.4.1 Heat of Reaction ................................ 11
2.4.2 Rules of Hierarchy .............................. 12
2.4.3 Calculation of Oxygen Balance and Fuel Values ... 12
References .................................................. 13
3 Ammonium Nitrate Explosives ................................. 15
3.1 Introduction ........................................... 25
3.1.1 Chronology ...................................... 15
3.2 " Design of Commercial Explosives ..................... 16
3.2.1 Importance of Oxygen Balance .................... 16
3.2.2 Physical, Performance, and Safety
Requirements .................................... 17
3.3 Tests .................................................. 17
3.3.1 Ballistic Mortar Test ........................... 18
3.3.2 Trauzl Lead Block Test .......................... 19
3.3.3 Velocity of Detonation (VOD) .................... 20
3.3.4 Gap Test and Continuity of Detonation Test ...... 22
3.3.5 Aquarium Test ................................... 23
3.3.6 Double Pipe Test ................................ 23
3.3.7 Cylinder Test (Crashing Strength) ............... 24
3.3.8 Plate Dent Test ................................. 24
3.3.9 Underwater Test (UWT) ........................... 24
3.3.10 Crater Test ..................................... 26
3.4 Assessment of Safety and Stability Characteristics ..... 27
3.4.1 Impact Test ..................................... 27
3.4.2 Torpedo Friction Test ........................... 27
3.4.3 Accelerated Hot Storage (ageing Test) ........... 27
3.4.4 Cold Temperature Storage Test ................... 28
3.4.5 Thermal Stability Tests Using DTA and TGA
Procedures ...................................... 28
3.5 Summary ................................................ 29
References .................................................. 29
4 Ammonium Nitrate and AN/FO .................................. 31
4.1 Introduction and History ............................... 31
4.2 Physical and Chemical Properties of Ammonium Nitrate ... 32
4.2.1 Basic Data ...................................... 32
4.2.2 Decomposition Chemistry of AN ................... 32
4.2.3 Phase Transition in AN and its Importance in
Explosives ...................................... 33
4.3 Manufacture of Ammonium Nitrate ........................ 35
4.3.1 Prilled Ammonium Nitrate ........................ 36
4.4 Ammonium Nitrate Fuel Oil Explosives ................... 39
4.4.1 Background ...................................... 39
4.4.2 AN/FO Manufacture ............................... 39
4.4.2.1 Mixing Process and Equipment ........... 39
4.4.2.2 Continuous Process ..................... 40
4.4.2.3 Bulk Delivery Systems .................. 40
4.4.3 Properties of AN/FO ............................. 41
4.4.3.1 Physical ............................... 41
4.4.3.2 Oil Absorbency and Porosity/Bulk
Density/Crushing Strength .............. 41
4.4.3.3 Resistance to Effect of Temperature
Cycling ................................ 44
4.4.4 Characteristics of ANFO ......................... 45
4.4.4.1 Density/Strength ....................... 45
4.4.4.2 Strength of the AN/FO Explosive ........ 46
4.4.4.3 Energy Content of AN/FO ................ 46
4.4.4.4 Velocity of Detonation and Effective
Priming ................................ 47
4.4.4.5 Mechanism of Detonation Propagation
in AN/FO ............................... 49
4.4.4.6 Influence of Fuel ...................... 50
4.4.4.7 Effect of Moisture/Wet Boreholes/
Water-Resistant AN/FO .................. 50
4.4.4.8 Water-Resistant AN/FO .................. 52
4.4.4.9 Increasing the Energy of AN/FO and
its Fume Characteristics ............... 52
4.4.5 Safety Considerations in AN/FO .................. 55
4.4.6 Summary - AN/FO Explosives ...................... 56
4.4.7 Quality Checks .................................. 56
References .................................................. 58
Further Reading ............................................. 58
5 Slurries and Water Gels ..................................... 59
5.1 Development ............................................ 59
5.2 Design ................................................. 59
5.2.1 Large-Diameter Packaged Product (Water Gels) .... 60
5.2.2 List of Ingredients ............................. 60
5.2.3 Small-Diameter, Cap-Sensitive Water Gels ........ 60
5.2.4 Bulk Delivery Product ........................... 61
5.2.5 Basic Concepts of Formularion ................... 61
5.2.5.1 Oxygen Balance ......................... 61
5.2.5.2 Thumb Rules for Design ................. 62
5.2.5.3 Role of Water .......................... 63
5.2.5.4 Basic Composition and Process .......... 65
5.3 Process Technology ..................................... 66
5.3.1 Batch Process ................................... 66
5.3.2 Continuous Process .............................. 68
5.3.3 Packaging Systems ............................... 68
5.4 Quality Checks ......................................... 71
5.4.1 Raw Materials ................................... 71
5.4.2 End Product Specification ....................... 73
5.4.2.1 Development of New Formulations ........ 73
5.4.3 Role of Aluminum in Water Gels and Slurry
Explosives ...................................... 74
5.4.3.1 Atomized and Flake Powders ............. 74
5.4.3.2 Aluminum Water Reaction ................ 78
5.4.3.3 Important Tests for AL Powder for Use
in AN-Based Water Gel Explosives ....... 80
5.4.4 In-Process and Finished Product Checks .......... 84
5.4.4.1 Oxidizer Blend Composition ............. 84
5.4.4.2 Solid Ingredients ...................... 85
5.4.4.3 Liquid Ingredients ..................... 85
5.4.4.4 Mixing ................................. 85
5.4.4.5 Packing ................................ 86
5.4.5 Performance Tests ............................... 86
5.4.6 Safety Tests .................................... 87
5.4.6.1 Gap Test/COD ........................... 87
5.4.6.2 COD .................................... 87
5.4.7 Storage Tests ................................... 87
5.4.8 Gel Condition Evaluation ........................ 89
5.4.9 Waterproofness Test ............................. 90
5.4.10 Effect of (Hydrostatic) Pressure ................ 90
5.5 Process Hazards (Dust Explosions/Fire Hazards/Health
Hazards) ............................................... 91
5.5.1 Slippery Floor .................................. 92
5.5.2 Health Hazard ................................... 92
5.6 Role of GG ............................................. 92
5.6.1 Application in Water Gels and Slurries .......... 93
5.6.2 Specification of Typical GG Used in Water
Gels ............................................ 94
5.6.3 Cross-Linking ................................... 95
5.6.4 Mechanism of Hydration .......................... 96
5.7 Permissible Explosives ................................. 98
5.7.1 Design Criteria ................................. 98
5.7.2 Tests for Permissibility ........................ 99
5.7.3 Other Tests requirement ........................ 100
5.7.3.1 Deflagration Tests ........................... 100
5.7.4 Behavior of Water Gels in Permissibility
Tests .......................................... 101
5.7.5 Toxic Fumes and Typical Formulation ............ 104
5.7.6 Strength of Permissible Water Gels ............. 104
5.8 General Purpose Small-Diameter Explosives (GPSD) ...... 105
5.8.1 Design Criteria and Composition ................ 105
5.9 Sensitizers ........................................... 106
5.9.1 Inorganic ...................................... 106
5.9.2 Organic Sensitizers ............................ 107
5.9.3 Air/Gas/Synthetic Bubble Sensitizers ........... 108
References ................................................. 111
Further Reading ............................................ 112
6 Emulsion Explosives ........................................ 113
6.1 Introduction .......................................... 113
6.2 Concept of Emulsion Explosives ........................ 113
6.3 General Composition of Emulsion Explosives ............ 114
6.4 Structure and Rheology ................................ 115
6.5 Composition and Theory of Emulsion Explosives ......... 117
6.6 Manufacture ........................................... 118
6.6.1 Types of Emulsion Explosive Products ........... 118
6.6.2 Manufacturing Process .......................... 118
6.6.2.1 Batch Process ......................... 119
6.6.2.2 Semicontinuous Operation .............. 119
6.6.2.3 Fully Continuous Process .............. 120
6.6.2.4 Critical Equipment for Production of
Emulsion Explosives ................... 121
6.6.2.5 Pumps ................................. 122
6.6.2.6 Packaging Equipment for Emulsion
Explosives ............................ 122
6.6.3 Raw Material for Emulsion ...................... 123
6.6.3.1 Fuel Blends ........................... 123
6.6.4 Sensitizing in Emulsion Explosives ............. 225
6.6.4.1 Air Entrapment or Ocdusion while
Emulsification by Mechanical
Agitation ............................. 125
6.6.4.2 Chemical Gassing ...................... 125
6.6.4.3 Hollow Particles ...................... 126
6.6.5 Crystal Habit Modifiers ........................ 127
6.6.6 Emulsion Promoters ............................. 128
6.6.7 Emulsion Stabilizers ........................... 128
6.6.8 Emulsion Chemistry and Understanding
Emulsifiers: Key to Good Emulsions ............. 129
6.6.9 Concept of HLB and Its Use in Emulsification ... 133
6.6.9.1 Effect of Factors on Stability of
Emulsions ............................. 135
6.6.10 Polymer Systems in Emulsion Explosives ......... 138
6.7 Quality Checks ........................................ 139
6.7.1 Raw Materials .................................. 139
6.7.2 Process Audit .................................. 140
6.7.3 Special Tests for Emulsions .................... 141
6.8 Explosive Properties of Emulsion Matrix/Explosives .... 142
6.8.1 Channel Effect ................................. 144
6.9 Permissible Emulsions ................................. 145
6.10 General Purpose Small-Diameter (GPSD) Emulsion
Explosives ............................................ 147
6.11 Bulk Emulsions ........................................ 149
6.12 Heavy AN/FO ........................................... 152
6.13 Packaged Large-Diameter Emulsion Explosives ........... 153
References ................................................. 154
Further Reading ............................................ 155
7 Research and Development ................................... 157
7.1 Areas of Interest ..................................... 158
7.2 Development Work and Upscaling ........................ 159
7.3 Management of R&D ..................................... 162
8 Functional Safety during Manufacture of AN Explosives ...... 163
8.1 Introduction - Personal View Point on Safety .......... 163
8.2 Safety Considerations in AN Explosives ................ 165
8.2.1 In AN/FO ....................................... 165
8.2.2 In Slurries and Emulsions ...................... 166
8.2.3 Electrostatic Ignition ......................... 167
8.2.4 Lightning Protection ........................... 168
8.2.5 Runaway Reactions .............................. 168
8.2.6 Venting as Means of Protection ................. 170
8.2.7 Explosion Suppression Technology ............... 171
8.3 Explosion Hazards in Equipment ........................ 172
8.3.1 Hazards Associated with Pumping of
Explosives ..................................... 172
8.3.2 Possible Hazards during Packing ................ 175
8.4 Concluding Remarks .................................... 176
References ................................................. 177
9 Economics of AN-Based Explosives ........................... 179
9.1 In Manufacture ....................................... 179
9.2 In Applications ....................................... 181
9.2.1 Condition of Explosive ......................... 182
9.2.2 Coupling and Priming ........................... 183
9.2.3 Stemming and Confinement ....................... 184
9.2.4 Explosives-Rock Interaction .................... 185
9.2.5 Explosives Energy Optimization in Blasting .... 185
9.3 Blast Design .......................................... 186
9.4 Influence of Explosives in Underground Mining ......... 190
References ................................................. 193
10 Current Status and Concluding Remarks ...................... 195
Appendix A .................................................... 199
Appendix B: Guidelines for Investigation of an Accident ....... 203
B.l Introduction .......................................... 203
B.2 Detailed Inspection ................................... 204
B.3 Interviewing and Questioning .......................... 205
B.4 Collection of Samples ................................. 205
B.5 Examination of Witnesses .............................. 206
В.6 Examination of Dead/injured ........................... 206
Index ......................................................... 209
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