Selective Tribocharging of Particles for Separation

Abstract

Abstract

Electrophysical Characterisation of Powders

“…A more recent version of the apparatus has been constructed for measurements in vacuum as well, and for a larger range of vibration frequency and amplitude, as well as contact time. In this way, different rubbing systems can be simulated from gentle sliding, to high-velocity impingement [22,23,24,25,26]. 6 shows a photo of the apparatus consisting of three parts: a system for charging the particles, a device for feeding charged particles into the Faraday well, and a system for containing particles before processing.…”

“…When the semiconductor is in a temperature range where one type of charge carrier concentration predominates over the other, the following simple equations can be used to determine the charge carrier concentration n and p: 32 n = -~ ( -1 -) for n-type semiconductors (25) q·RH P = + ~ ( q -~H) for p-type semiconductors (26) The charge carrier mobility can be calculated with the equations: Rwcr f.!n=--~-for n-type semiconductors (27) Rwcr f.!p=+-~-for p-type semiconductors (28) where cr is the electric conductivity determined as explained in section 3.…”

Beitrag zur Untersuchung der triboelektrischen Aufladecharakteristik feindisperser Körnerschwärme

“…Diese optimalen Betriebspunkte liegen meist in Temperaturbereichen über 80 °C und stellen somit in vielen Aufbereitungs-Stammbäumen einen wirtschaftlich relevanten Faktor für die Anwendung der Elektroscheidung dar. Ciccu et al 5 führten Aufladeversuche an verschiedenen Mineralen in einem Aerozyklon durch und ermittelten in einem nachgeschaltenen Freifallscheider das Masseausbringen der Minerale an der negativen Elektrode in Abhängigkeit zur Aufgabetemperatur. Die Extremwerte des Masseausbringens stellten die oben erwähnten optimalen Betriebstemperaturen für das jeweilige Mineral dar.…”

Triboelectrostatic Cleaning of Coal In-Line Between Pulverizers and Burners at Utilities

“…It separates carbon-or the combustibles-from mineral matter within an electric field by using the differential charge that can be imparted on these particles. Differential charging is a consequence of particle-particle and particle-wall collisions and is dependent on differences in the surface properties of constituent particles within the coal [9][10][11][12][13][14][15][16].…”

“…Recent research on triboelectrification and electrostatic separation has evaluated scientific and engineering parameters which control triboelectrostatic processing [3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Most studies have employed tribocharging equipment constructed of copper to impart a differential charge on the combustibles and mineral matter.…”