DEM AS A TOOL FOR DESIGN AND OPTIMISATION OF MINERAL PROCESSING EQUIPMENT
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DEM AS A TOOL FOR DESIGN AND OPTIMISATION OF MINERAL PROCESSING EQUIPMENT


DisciplinaProcessamento de Minerais I211 materiais2.062 seguidores
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so the center of the finer middle stream falling from the impact plate is 
directly over the center of the bin, then equal amounts of the fines will fall into either side of the bin. The 
coarse material is mostly in the two outer streams falling from the impact plate. One stream falls into each 
hopper and so the amount and composition of coarse material in each hopper is essentially the same. The 
overall composition of the material in each hopper is then the same, (even though there are differences in the 
distribution of the coarse and fine within each hopper). 
If the impact plate is placed closer to the incoming conveyor then a larger fraction of the fines will fall 
into the closer hopper (the left one in Figure 7c) and the left hopper will have a finer composition than the 
right one. Conversely, if the impact plate is located further away then more of the finer material will fall into 
the far hopper (on the right in Figure 7c) and this will have a finer composition. The positioning of the 
impact plate is therefore critical as this determines the split of fine material between hoppers. 
 We note here that extreme positions of the impact plate will also start to affect the split of the coarse 
material between hoppers. The sideways position of the impact plate is not important as long as the entire 
incoming stream is deflected by the plate. These observations have been made on the basis of one simulated 
configuration, but the general understanding obtained can be expected to apply for a range of belt speeds and 
tonnages and for variants of the conveyor and bin geometry. The critical aspects required to generate the 
composition variations are the asymmetric orientation of the incoming conveyor, the presence of an impact 
plate and the initially vertically segregated material on the incoming belt. 
 
CONCLUSIONS 
 
DEM simulations of applications relating to the storage, transport, sampling and separation of particulate 
solids have shown that: 
! A broad variety of coarse particulate mineral processing equipment can be successfully modelled. 
! Relevant information relating to the important issues for each of the types of equipment/processes can be 
predicted. This includes flow rates, segregation effects, particle degradation and damage to equipment for 
transport equipment; sample bias for sample cutters; segregation effects, flow rates and wall stresses for 
storage and reclaim equipment and separation efficiency for vibrating screen decks. 
! Enhanced understanding of the particulate flows in the equipment and of the important issues for each 
case. 
 
ACKNOWLEDGEMENTS 
 
The author would like to acknowledge the contributions of Geoff Robinson to the development of the 
capability to analyse cross belt conveyor sampling over the last decade. Also acknowledged is the work of 
Phil Owen in performing the screw conveyor simulations. 
 
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