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This study investigated the influence of electrode configuration on corona discharge and particle collection from 300 K to 900 K. Electrodes of different shapes (rod, saw, and screw), diameters (3, 5, and 8 mm), and intervals (55, 110, and 165 mm) were tested in an experimental-scale electrostatic precipitator (ESP). Results showed that a high current was generated with a saw electrode and increased the particle collection efficiency, particularly for fine particles (diameter smaller than 0.1 μm), with the best particle collection efficiency being 99.8% at 300 K. However, with an increase in temperature, the rod electrode obtained an applied voltage higher than those of other electrode types and, as a result, generated relatively high particle collection efficiencies at 700 K and 900 K. Increasing the electrode diameter from 3 mm to 5 mm improved the applied voltage, whereas increasing this diameter from 5 mm to 8 mm reduced the discharge current. Among electrodes with different diameters, the electrode with a diameter of 5 mm achieved the best particle collection efficiency (87.4%) at 900 K. The applied voltages of the electrodes with different intervals were almost similar, but the discharge currents varied significantly. The best particle collection efficiencies were achieved by the electrode with an interval of 55 mm at 300 K and 500 K, but at 700 K and 900 K, the electrode with an interval of 110 mm obtained the best result. The interval between electrodes should be expanded with an increase in temperature to avoid the offsetting of electric field between neighboring electrodes. [ABSTRACT FROM AUTHOR]

An experimental-scale electrostatic precipitator (ESP) was built to investigate the characteristics of corona discharge, particle migration, and particle collection at various temperatures ranging from 300 K to 900 K. The variations in particle collection efficiencies and migration velocities with temperature, applied voltage, current density, energy consumption density, particle concentration, and flue gas velocity were obtained. Both onset and spark voltages decreased with an increase in temperature and resulted in a decrease in particle collection efficiency and particle migration velocity. At the same voltage, a large current was generated at high temperature; particle charging was enhanced, and high particle collection efficiencies and particle migration velocities were obtained. At the same current and energy consumption densities, the particle collection efficiencies decreased because of the low electric field intensity. The increase in particle concentration was favorable to particle collection and improved the particle migration velocities. The increase in flue gas velocity reduced the particle collection efficiencies and had minimal influence on the particle migration velocities. [ABSTRACT FROM AUTHOR]