| Preface | p. xi |
| Acknowledgements | p. xiii |
| The range and application of electrostatic precipitators | p. 1 |
| Introduction | p. 1 |
| Arrangement and basic operation of a precipitator | p. 4 |
| Versatility | p. 10 |
| Characteristics of the gases as they affect precipitator design | p. 11 |
| Composition | p. 11 |
| Temperature | p. 12 |
| Pressure | p. 13 |
| Gas flow rate | p. 13 |
| Viscosity and density | p. 14 |
| Characteristics of the suspended material and their possible impact on precipitator performance | p. 14 |
| Concentration | p. 14 |
| Composition and electrical resistivity | p. 15 |
| Particle sizing | p. 16 |
| Particle shape | p. 17 |
| Particulate surface properties | p. 18 |
| Sizing of electrostatic precipitators | p. 19 |
| References | p. 19 |
| Fundamental operation of an electrostatic precipitator | p. 21 |
| Introduction | p. 21 |
| Ion production | p. 22 |
| Particle charging | p. 27 |
| Particle migration | p. 29 |
| Particle deposition and removal from the collector electrodes | p. 32 |
| Precipitator efficiency | p. 33 |
| Practical approach to industrial precipitator sizing | p. 34 |
| References | p. 36 |
| Factors impinging on design and performance | p. 39 |
| Effect of gas composition | p. 39 |
| Impact of gas temperature | p. 40 |
| Influence of gas pressure | p. 43 |
| Gas viscosity and density | p. 44 |
| Impact of gas flow rate and gas velocity | p. 44 |
| Gas turbulence | p. 46 |
| The importance of gas distribution | p. 48 |
| Correction by model testing | p. 50 |
| Computational fluid dynamic approach | p. 51 |
| Effect of particle agglomeration | p. 54 |
| Particulate cohesivity effects | p. 58 |
| References | p. 61 |
| Mechanical features impacting on electrical operation | p. 63 |
| Production of ions | p. 63 |
| Quasi-empirical relationships | p. 66 |
| Discharge electrode forms | p. 68 |
| Spacing of discharge electrodes | p. 71 |
| Collector electrodes | p. 72 |
| Specific power usage | p. 73 |
| Precipitator sectionalisation | p. 75 |
| High tension insulators | p. 76 |
| Electrical clearances | p. 78 |
| Deposit removal from the collector and discharge systems | p. 80 |
| Impact of collector deposits on electrical operation | p. 80 |
| Measurement of rapping intensity on dry precipitator collectors | p. 84 |
| Hopper dust removal | p. 85 |
| Re-entrainment from hoppers | p. 86 |
| References | p. 86 |
| Development of electrical energisation equipment | p. 89 |
| Early d.c. energisation techniques | p. 89 |
| Development of a.c. mains frequency rectification equipment | p. 91 |
| Valve rectifiers | p. 91 |
| Mechanical switch rectifier | p. 92 |
| Metal oxide rectifiers | p. 97 |
| Silicon rectifiers | p. 98 |
| HT transformers | p. 101 |
| Transformer losses | p. 103 |
| Cooling of transformer and rectifier equipment | p. 105 |
| Primary input control systems | p. 107 |
| Manual methods | p. 107 |
| Motorised methods | p. 108 |
| Saturable reactors | p. 109 |
| Silicon controlled rectifiers (SCRs) | p. 110 |
| Automatic control systems | p. 113 |
| Early current control | p. 113 |
| Voltage control method | p. 114 |
| Computer control methods | p. 115 |
| Summary of developments | p. 116 |
| References | p. 117 |
| Modern mains frequency energisation and control | p. 119 |
| Basic operation of mains frequency equipment | p. 119 |
| High voltage equipment supply ratings | p. 123 |
| Mean precipitator current | p. 124 |
| Primary r.m.s. current | p. 125 |
| Precipitator peak voltage under no-load conditions | p. 125 |
| Apparent input power | p. 125 |
| Practical example | p. 126 |
| Influence of the linear inductor | p. 126 |
| The main function of the inductor | p. 126 |
| Physical implementation of the linear inductor | p. 128 |
| Automatic voltage control and instrumentation | p. 129 |
| Secondary metering approach | p. 130 |
| Primary metering system | p. 131 |
| Opacity signal and full energy management | p. 132 |
| Basic AVC control principles | p. 135 |
| Back-corona detection and corona power control | p. 140 |
| Specific power control | p. 142 |
| Control by the use of intermittent energisation | p. 142 |
| Supervisory computer control using a gateway approach | p. 143 |
| Advanced computer control functions | p. 144 |
| References | p. 146 |
| Alternative mains frequency energisation systems | p. 147 |
| Two-stage precipitation | p. 147 |
| Air cleaning applications using positive energisation | p. 147 |
| Two-stage precipitation as applied to power plant precipitators | p. 149 |
| Intermittent energisation | p. 151 |
| Basic principles of intermittent energisation | p. 152 |
| Comparison of IE with traditional d.c. energisation | p. 153 |
| Collection efficiency evaluation | p. 156 |
| Pulse energisation | p. 159 |
| Introduction | p. 159 |
| Electrical configurations | p. 160 |
| Electrical operation with pulse chargers | p. 164 |
| Major operational aspects of pulse energisation | p. 165 |
| Current control capabilities | p. 166 |
| Current distribution on collectors | p. 167 |
| Electrical field strength in the inter-electrode area | p. 167 |
| Particle charging | p. 168 |
| Power consumption | p. 168 |
| Worked example of energy recovery | p. 169 |
| Collection efficiency | p. 169 |
| Typical applications using pulse energisation | p. 170 |
| References | p. 171 |
| High frequency energisation systems | p. 175 |
| Introduction | p. 175 |
| Development of switch mode power supply systems | p. 176 |
| Expected operational improvements | p. 176 |
| System requirements | p. 177 |
| Design considerations | p. 178 |
| SMPS circuit configurations | p. 179 |
| Input rectification stage | p. 179 |
| Three phase six switch mode UPF converter | p. 180 |
| Three phase boost type UPF rectifier | p. 181 |
| Three phase full wave rectifier with a.c. side filtering | p. 182 |
| Comments on the various input stage topologies | p. 183 |
| High frequency inverter stage | p. 184 |
| PWM controlled 'H' bridge inverter | p. 185 |
| Resonant converter | p. 185 |
| Matrix converter | p. 187 |
| Comments on the various inverter topologies | p. 188 |
| High voltage, high frequency transformer | p. 188 |
| Parasitic capacitance | p. 188 |
| Magnetic leakage flux | p. 188 |
| Insulation and electric stress management within the transformer | p. 189 |
| Corona effects | p. 190 |
| Transformer output rectification | p. 190 |
| Short duration pulse operation | p. 190 |
| Advantages of the SMPS approach to precipitator energisation | p. 191 |
| Review of the various topologies leading to a prototype SMPS development under a UK EPSRC grant | p. 192 |
| Operational field experience with SMPS precipitator energisation | p. 192 |
| SMPS system of Supplier No. 1 | p. 194 |
| SMPS system of Supplier No. 2 | p. 196 |
| SMPS system of Supplier No. 3 | p. 204 |
| SMPS system of Supplier No. 4 | p. 209 |
| Advantages/conclusions reached from these field trials | p. 212 |
| References | p. 213 |
| The impact of electrical resistivity on precipitator performance and operating conditions | p. 215 |
| Particle composition | p. 215 |
| Particle resistivity | p. 216 |
| Measurement of particulate resistivity | p. 217 |
| Resistivity effects on low temperature power station precipitators | p. 220 |
| Correlation between precipitator performance and particulate resistivity | p. 222 |
| Low resistivity ash and its effect on performance | p. 226 |
| Equipment for flue gas conditioning | p. 228 |
| Sulphur trioxide conditioning | p. 228 |
| Ammonia conditioning | p. 230 |
| Humidity conditioning | p. 232 |
| Reducing inlet gas temperature | p. 233 |
| Summary of resistivity effects on precipitator performance | p. 233 |
| References | p. 236 |
| 'On-line' monitoring, fault finding and identification | p. 239 |
| Corrosion condition monitoring | p. 239 |
| Electrical operating conditions | p. 248 |
| TR control cubicle information | p. 249 |
| TR set panel meter readings | p. 249 |
| TR equipment lamp test | p. 249 |
| Deposit removal from the internals | p. 253 |
| DE and collector system voltage/current relationships | p. 253 |
| Clean air load characteristic | p. 254 |
| Operational curves with gas passing through the system | p. 255 |
| Dirty air load test, without gas passing through system | p. 258 |
| Collector/discharge electrode alignment | p. 259 |
| High tension insulators | p. 259 |
| Hoppers | p. 260 |
| Gas distribution and air inleakage | p. 261 |
| Changing inlet gas conditions | p. 261 |
| Particle resistivity | p. 261 |
| Particle sizing and opacity monitoring | p. 262 |
| Systematic fault finding procedure | p. 264 |
| References | p. 264 |
| Index | p. 265 |
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