Ball mill condition		Capacity (kg/hour)	power (kW)	energy cost (?ton)	wear (?ton)	investment cost (?	capital cost in ?ton	diameter of ball mill (m)	length of ball mill (m)	speed (rpm)	speed (rph)	weight of balls (N)	height of drop (m)	total cost (?ton)
Scale	residence time (seconds)	Capacity (kg/hour)	power (kW)	energy cost (?ton)	wear (?ton)	investment cost (?	capital cost in ?ton	diameter of ball mill (m)	length of ball mill (m)	speed (rpm)	speed (rph)	weight of balls (N)	height of drop (m)	total cost (?ton)
Lab^*	300	192	0.23	0.12	0.12	4294	4.97	0.6	0.3	45	2700	600	0.5	5.20
Ind^**	300	30,000	36.00	0.12	0.12	116,281	0.84	1.2	3	22.5	1350	96,000	1.0	1.08
Lab	90	640	0.23	0.04	0.04	4294	1.49	0.6	0.3	45	2700	600	0.5	1.56
Ind	90	30,000	10.80	0.04	0.04	53,167	0.38	1.2	1	22.5	1350	28,800	1.0	0.45