What is ball mill?

Ball mills are a similar shape to that of the rod mills except that they are shorter with length to diameter ratios of 1 to 1.5. As the name implies, the grinding media in these mills are steel balls. The particles size of the feed usually does not exceed 2.5 cm. The grinding is carried out by balls being carried up the side of the mill such that they release and fall to the point where they impact the ore particles in trailing bottom region of the slurry. If the mill is rotated too fast, the balls can be thrown too far and just strike the far end of the mill and conversely, if the mill is rotated to slow, the efficiency of the grinding process significantly reduced. Ball mills are suited for finer grinding as larger particles do not impede the impact on to smaller particle as in rod mills.

Advantages of wet grinding

Wet grinding is generally used in mineral processing operations because of the overall economies of operation.
The advantages of wet grinding are:
1. It consumes lower power per ton of product.
2. It has higher capacity per unit mill volume.
3. It makes possible the use of wet screening or classification for close product control.
4. It eliminates the dust problem.
5. It makes possible the use of simple handling and transport methods such as pumps, pipes, and launders.