Abstract:

2×670MW coalfired units adopted a directblowing pulverizing system. When the coal quality was poor, the coal bunker was frequently blocked. The original methods which were vibration method, air cannon method, and screw dredge method worked ineffectively. A helical pneumatic dredging device is used to reduce the blockage of the coal bunker dramatically and improve the operation reliability of the system. It also avoids the problem of load reduction caused by coal blockage.

Key words:

coal bunker, coal quality, blockage, rotary air flow, antiblockage