Cover of Applied Electrostatic Precipitation

Applied Electrostatic Precipitation

K. R. Parker, ed.

(1997) xvi + 520 pages

Increased awareness of the effects of atmospheric pollution and ever-tightening legislation have challenged the precipitation industry to increase performance at economical costs and operation of the precipitators has to be maintained at optimum levels to prevent penalizing consequences to plant operators. The technique of electrostatic precipitation has undergone considerable development over the past decades and is now the method of choice for limiting particulate discharges.

This volume is a good authoritative and practical guide for the industry specialist with contributions by leading experts in the field of electrostatic precipitation. Even the non-specialist will find this worthwhile as the basic theories of precipitation from both fluid and electrodynamic views are clearly presented.It also includes practical designs and gaseous and particulate features which impact precipitator performance. Future developments of precipitators are covered for the designer and developer. This mammoth compendium is a must have for the industry specialists to keep updated on the field.

::Why an electrostatic precipitator?: K.R. PARKER; Introduction; Control system characteristics; Control operating principles@ Inertial separation; Wet scrubbers; Fabric filter; Electrostatic precipitation @ :Summary of control system properties @ ::Milestones in the history of precipitation: K.R. PARKER; Precipitator installations@ Early investigations and developments; Full-scale precipitator developments @ :Development of electrical supplies@ Rectifier types; Primary control systems; Automatic control systems @ :References @ ::Basic and theoretical operation of ESPs: C. RIEHLE; General remarks; Ion production@ Principles; Corona initiation field strength; Corona onset voltage; Current-voltage relationship; Electrical field distribution @ :Particle charging@ Charging process; Cochet's charging model; Time dependence and saturation charge @ :Particle migration@ Equation of motion; Theoretical migration velocity @ :Measuring and modelling particle separation@ Grade efficiency and total efficiency; Laminar model; Deutsch model; Flow field and particle trajectories; Diffusivity models @ :Deposition; Removal; References @ ::Mechanical design considerations for dry precipitators: F. KNUTTSEN and K.R. PARKER; Introduction; Discharge electrodes; Discharge electrode mounting; Collectors; Casings; Hi gh voltage insulators; Rapping; Hoppers; Electrical clearances; References @ ::Aerodynamic factors affecting performance: L. LIND; Introduction; Turbulence and secondary flow@ Historical resume; Turbulence; Secondary flow; Numerical flow model @ :Gas velocity; Gas distribution@ Standards; Residence time; Space charge; Re-entrainment; Erosion; Sneakage and sweepage; Optimal distribution @ :Model testing; Computational fluid dynamics; Field testing; Dust build-up and wear; References @ ::The physical and chemical properties of particles and their effect on performance: K. PORLE and K.R. PARKER; Particle size and shape@ Particle sizing; Particle shape and structure @ :Agglomeration; Cohesivity; Particle electrical resistivity; Chemical compositon and reactivity; References @ ::Performance design considerations: C. COTTINGHAM; Introduction; What are we trying to achieve? Assessment of the process@ Typical assessment @ :Plate spacing; Configuring the ESP; Conclusions; References @ ::Electrical operation of precipitators: V. REYES; Introduction; Precipitator performance and electrical energization@ Examples @ :Corona suppression and space charge effects@ Electrical characteristics with air load; Characteristics with dust load @ :High tension sectionalization; Traditional DC energization@ Basic principles; High voltage power supply ratings; Influence of the linear inductor @ :Intermittent energization@ Basic principles; Comparison with traditional DC energization; Collection efficiency @ :Automatic voltage control and instrumentation@ Introduction; Instrumentation; Basic control principles; Spark detection and voltage recovery; Back-corona detection and corona power control @ :Pulse energization@ Introduction; Electrical configuration; Main features of pulse energization; Power consumption; Collection efficiency; Applications; Summary @ :Supervisory computer control@ Stand-alone computer; Supervisory computer control via a gateway unit; Advanced control functions @ :Appendix; References @ ::Precipitator sizing methods: C. PAULSON; Theoretical considerations@ Basic dust-collection equation for gas in a duct; Electrostatic precipitation; Improvement of the Deutsch equation; Factors affecting electrostatic precipitation @ :Practical considerations@ Interpretation of test results @ :Precipitator modelling@ Mathematical modelling; Practical testing @ :References @ ::Models of electrostatic precipitators: M. REA; Basic concept@ The Deutsch equation; Charging of particles and the modified Deutsch equation @ :The modern approach to computer modelling@ Early models; Model by Canadas et al.; Modelling at Padova university @ :@ ::Sampling and analysis for particles and heavy metals in gas streams: G.B. NICHOLS and E.B. DISMUKES; Sampling and analysis; Heavy metals@ General considerations; Sampling methods for multiple types of heavy metals; Sampling methods for mercury alone; Metal analysis in the laboratory; Prospects for real-time monitoring @ :References @ ::The commissioning of electrostatic precipitators: D.A. STYLER and J.C. WESTBURY; Introduction; Mechanical commissioning@ Post construction stage; Cold commissioning; Hot commissioning @ :Electrical commissioning@ An overview; Managers and commissioning; Familiarity revisited; The programme ­ who writes the programme and when?; Monitoring @ :Process commissioning@ Hot commissioning; Back to the real world! @ :@ ::Dry type precipitator applications: K. PORLE and K.R. PARKER; Introduction; Power generation industry@ Bituminous coals; Anthracite coals; Subbituminous coals; Brown coals; Lignites; Oil-based fuels @ :The cement industry@ Wet process manufacture; Semi-wet processing; Dry process production plant; Alkali bypass plant; Clinker cooler precipitators; Cement mill precipitators @ :General steam-raising plant@ Moving grate combustors (chain grate, reciprocating and cyclic beds); Fluidised bed units @ :Biomass-fired steam-raising plants@ Wood chip combustion; Chicken litter, etc.; Municipal wastes @ :Iron and steel works@ Sinter plants; Pelletising plants; Steel making; Operations involving the casting of hot metal @ :Non-ferrous industries@ Copper and nickel recovery @ :Aluminium smelting; Paper and pulp industry@ Bark firing; Cellulose pulp production; Lime sludge burning; Magnesium sulphate burning @ :Conclusions; References @ ::The wet electrostatic precipitator: design and applications: K.R. PARKER; Introduction; Design considerations@ Dust deposition and removal @ :Discharge electrodes; High tension insulators; Casing/hopper design; Water treatment; Materials of construction; Electrical energisation; Typical applications of wet precipitators@ Applications in the iron and steel making fields; Applications in the chemical industries; Applications following acid gas scrubbers; Incineration-type processes; HAC discharges; Glass manufacturing; Other applications @ :@ ::The mist precipitator: design and applications: K.R. PARKER; Introduction; Applications of mist precipitators@ Collection of sulphuric acid mist; Gas detarring; Collection of radioactive particles; Other mist precipitator applications @ :Conclusions @ ::Upgrading of existing precipitator efficiencies: @ K.R. PARKER and H. KRIUMONT @ Modifications/changes to existing plant Assessment of required performance improvement; Performance improvement modification options; Alternative solutions@ Electrical; Mechanical changes @ :@ Precipitator improvements achieved by changing the electrical resistivity of the particulates Change of temperature/relative humidity of the gases; Flue gas additives to improve performance @ Theory, principles of operation, equipment and applications of flue gas conditioning (FGC) Introduction; Electrical resistivity@ Prediction of fly ash resistivity; Resistivity effects in ESPs @ :Flue gas conditioning@ Conditioning by sulfur trioxide; Ammonia conditioning; Dual flue gas conditioning; Balance of plant impact @ :Flue gas conditioning equipment@ SO3, FGC systems; Ammonia FGC systems ­ design features; ESP power consumption; Mixing requirements @ :Application of flue gas conditioning in converting hot-side fly ash precipitators to cold-side operation@ Introduction; Flue gas conditioning; Installation design; FGC operation; Economics; Conclusions @ :FGC systems ­ optimization@ General; Theoretical approach; Procedural approach; Statistical approach; Rapper adjustments; Data collection @ :Conclusions; References @ ::Possible future developments in the field of electrostatic precipitation: K.R. PARKER, C. RIEHLE and H. KRIGMONT @ Electrical developments High frequency power conversion or switched mode power supplies; Nanosecond pulse operation and acid gas control @ Use of natural sulphur dioxide as a feed stock for flue gas conditioning systems: flue gas conditioning today and tomorrow Background; 'Native' or 'internal' feed stock FGC technologies@ 'Slip-stream' FGC systems; In-duct FGC systems @ :In-situ: gas conditioning (IGC) approach@ Variable exposed area IGC system; Variable catalyst temperature IGC system @ :Variable flow lGC system; Catalyst selection @ High temperature/high pressure precipitators for advanced power generation systems Fundamentals; Voltage and current; Particle charging; Particle migration; Grade efficiency; Open questions@ Electrical resistivity; Mechanical stability of material; Rapping; Electrical insulation; Emptying of hoppers; Electrical power consumption @ :Symbols; References @ Computer sizing of precipitators @