# amit 135: lesson 7 ball mills & circuits – mining mill

Wet Ball Mill = kg kWh = 0.16(A i-0.015) 0.33; Dry Ball Mill = kg / kWh = 0.023A i 0.5; Replacement Ball Size. Rowland and Kjos proposed the use of their equation for the determination of the initial and replacement media size. Azzaroni (1981) and Dunn (1989) recommended the use of the following expression for the size of the makeup media: