PROCESS FOR REMOVAL OF TROUBLESOME MINERAL MATTER FROM PULVERIZED COAL

摘要

PROCESS FOR REMOVAL OF TROUBLESOME MINERAL MATTERABSTRACT OF THE DISCLOSUREA system for pulverizing coal to be burned in afurnace (20), where nearly all of the coarse ash particles areremoved from the coal prior to its introduction to thefurnace. The system includes a pulverizing mill (10) having afirst classifier (12) in its outlet for separating some of thelarge, heavy particles and returning them to the pulverizer. Asecond classifier (16) is connected to the first classifier,and includes a curved duct (68) wherein the solid particlesbeing carried in an airstream are thrown outwardly against anouter wall. A skimmer blade (78) extending through the outerwall skims off a percentage of the large, heavy particles, thepercentage depending on how much coarse ash the coal streamcontains. The rest of the coal particles are conveyed to afurnace and burned therein. The separated large, heavyparticles are passed through an ionizer (30) and then throughan electrostatic separator (34), where the inorganic particlesare separated from the coal particles. The coal particles canthen be conveyed to the furnace or sent back to the pulverizerfor further grinding.