Adjustable mill classifier

摘要

A classifier [100] is disclosed that employs adjustable vanes [140] that may be interactively adjusted to change the distribution of fuel particle sizes that are passed on to a furnace. The classifier employs a frame [133] having a plurality of windows [131] each having an adjustable vane [140]. A control ring [160] is rotated with respect to the frame [133] to simultaneously move links [150] connected between the control ring [160] and the vanes [140]. This causes the vanes [140] to open or close, changing the air flow path and changing the size distribution of particles passing through the classifier [100] to the furnace. The system may include an adjustment system [260] that can automatically sense particle size to optimize several physical parameters related to particle size.

主权项

1. A classifier system for separating coarser particles from finer particles entrained in an upward air stream comprising:
a housing having a general circular cross section; a truncated cone inside of the housing having a larger section at its top and a small cone outlet at its bottom, the cone defining an inner chamber; an outer chamber between the housing and the cone adapted to receive coarser and finer particles entrained in the upward air stream; a classifier ring at the top of the cone having a frame with a plurality of windows with vanes hinged adjacent to each window; wherein the vanes are adjustable to partially or fully close the windows thereby affecting the size of particles allowed through them and into the inner chamber; a fuel tube outlet above the classifier ring adapted to allow the air stream to exit the classifier system; and an adjustment system having: at least one pressure sensor upstream of the classifier ring to measure air pressure entering the classifier ring; at least one pressure sensor downstream of the classifier ring to measure air pressure exiting the classifier ring; a coarseness sensing device adapted to sense particle size exiting the fuel tube outlet; and, a control unit adapted to receive signals from the sensors and calculate a vane setting.