Coal pulverizer purifier classifier

Abstract

A fuel coal processing system is provided which consists of a centrifugal type pulverizer, a coal purifier and an optional fuel coal size classifier, all combined into one integral, cooperatively acting, fuel coal preparation device. The pulverizer consists of a pair of opposed multicup concentric ring rotors, mounted on a common axis, counter rotating at relatively high speed, an axially located feed tube through which material is fed into the center of the rotor system and then is thrown tangentially, progressively and outwardly from ring to ring on each of the counter rotating rotors thereby being reduced in size by the repeated high speed impacts and skidding abrasion associated with the process. The purifier consists of an annular ring nozzle surrounding the outer periphery of the pulverizer rotors through which high velocity air streams upwardly through the spray of pulverized material exiting the pulverizing rotors to vertically accelerate the less dense pure coal particles to strata relatively higher than the more dense impure material. The pyritic material is split off and rejected while the coal product then passes through size classifier means. Oversize coal is thrown out of the air stream and is returned to the mill for further reduction. Triboelectrostatic purification means may also be used alone or in conjunction with the aerodynamic means to more effectively handle different conditions and kinds of coal.

Dependencies are inferred from the claim text.