Comparative experimental study of two grinding media

Spherical grinding media (balls) are the most widely used media for comminution of ores by grinding.

One way to optimize the grinding process in a tumbling mill is associated with the development and testing of a new media shape. by modelling simulations study of the behavior of two types of grinding media (balls and tetraballpebs) in the girding process was conducted to determine the possible advantages of the new media shape. Tetraballpebs are in the shape of tetrahendrons with spherical convex walls.

D305 mm and L305 mm Bond ball mill sizes were used in the experiment. They are modeled milling tetraballpebs bodies corresponding by weight to five ball sizes, namely 3/3, 7/8, 1, 11/4 and 11/2 inches which form the grinding media used in a Bond ball mill. They are cast steel grinding bodies.

Studies carried out with both types of grinding media include equal number of milling bodies of the same weight and volume. Having thus ensured a uniform mass of the grinding media and the same number of milling bodies, all  other  conditions and process parameters being identical, conclusions can be drawn about the influence of the grinding media shape on the grinding process.

Compared to steel balls, the tetraballpebs used in the laboratory tests carried out in closed cycle by Bond ball mill and the study of the rate of grinding gave five to six percent higher yield of a control  size of minus 0.1 mm.

Measurements of the Bond ball mill power consumption demonstrated that tetraballpebs grinding media achieved energy saving of 4.7 per cent for the production of one gram of the control size of minus 0.1 mm.