1.闭路粉碎铝土矿的分级从铝土矿溶出氧化铝时,为了缩短溶出时间,提高溶出率,需将铝土矿粉碎。欧洲老厂采用闭路干法粉碎工艺,分级有的采用旋风收尘器,但现在,世界上几乎所有工厂都采用湿法粉碎工艺。湿法粉碎时主要使用耙式分级机,例如,美国的某工厂就是采用道尔公司的耙式分级 1. Closed-circuit crushed bauxite classification Dissolved alumina from bauxite, in order to shorten the dissolution time, increase the dissolution rate, the bauxite should be crushed. The European old factory adopts the closed-circuit dry-process crushing process, and the cyclone dust-catcher is adopted at some levels, but nowadays, almost all the factories in the world adopt the wet crushing process. Wet crushing mainly used rake graders, for example, a factory in the United States is to use Dow’s rake grading