Published Paper Details:

Fly ash particles, which are produced from coal fired thermal power stations in the form of suspension in the flue gas from combustion units, contribute to an increased suspended particulate matter (SPM) in surrounding environment. In order to reduce emission levels of SPM, various devices, such as cyclone separator, bag filter and/or electrostatic precipitator (ESP) are employed. On the other hand, ESP is most popularly used at thermal power stations to reduce SPM levels. Fundamental principle of operation of an ESP is that flue gas is forced to pass through an electrical field, wherein SPM get electrically charged. Charged particles are then deflected across the field and collected on a grounded plate. ESP process involves i) Charging of particles flowing between electrodes; ii) Migration and collection of particles on oppositely charged plates; iii) Dislodging particles off the plates and into hoppers; and (iv) Removal of material from hoppers. Frequency and intensity of rapping is important, for it is necessary to minimize rapping re-entrainment and maximize collection efficiency. Rapping should facilitate dislodgement of deposited particulate media from collector surface in an agglomerated form, large enough to fall through the gas flow into receiving hoppers, rather than exploding the layer from collection surface, which may result in severe particle re-entrainment. Performance of ESPs is affected by the characteristics of coal burnt and the properties of ash procured. Poor performance has been associated with low sulphur coals, but establishing a relationship is strenuous. This study correlates resistivity with various constituents that affect it and also the effect of resistivity on precipitator performance as resistivity is the first of many parameter used as a guide for precipitator performance and migration velocity quantification.