Question1:

a) A lead bearing ore was ground in a 2.26m (inside diameter) wet overflow ball mill rotating at 75% critical speed. The feed was sized and determined to be F80=500m with the desired P80 of 160m. Determine the capacity of the ball mill if b=7.9t/m3,Wi= 19.4kWh/t, bed porosity of 0.45 , and a correction factor of 1.1 . b) What is the capacity if the diameter is 4m