| 摘要 |
<p>PURPOSE:To separate ash in an extremely high removal ratio, by preliminarily adjusting the average particle size of stock fine powdery coal to be subjected to electrostatic separation treatment to a predetermined range. CONSTITUTION:The particle size of stock fine powdery coal is preliminarily adjusted so that the average particle size is 1-10mum and a max. particle size is 40mum or less by finely pulverizing treatment using a dry mill. The stock fine powdery coal, which received the adjustment of a particle size, is transported by an air stream with ambient temp. and humidity and changed in a dry electric separator 2 along with transport air in such a state that the concn. of coal in air is adjusted and held to 150-70g/m<2>. If charged stok fine powdery coal is subjected to electrostatic separation treatment at an air passing speed of 0.2m/s or more under a corona discharge state in the electric separator 2, an ash separation/removal ratio of 100-30% can be obtained.</p> |
