Abstract: NO.2 unit of one power plant is a 300 MW subcritical unit.The boiler adopts the single-furnace、tangential circle combustion method and the storage steel mill system. During the overhaul period, the coarse powder separators corresponding to the A/B/C mills have been reconstructed.changed from The original dual-axis coarse powder separator to dynamic separator. After the transformation,the fineness and uniformity of pulverized coal have been greatly improved,which is beneficial to the ignition and combustion of pulverized coal.

Key words: milling system, mill output, mill fineness, uniformity, dynamic separators