MATERIAL RETENTION TIME IN A BALL MILL VRM Page 1 .
Aug 11, 2010· Re: MATERIAL RETENTION TIME IN A BALL MILL VRM. You could do that by measuring the material flowrate Q[tons/h] through the mill as well as the quantity M[tons] of material that accumulates within the mill. The retention time, also called residence time, is the ratio (M/Q) [h] .