In the crushing sector of a ferrosilicon foundry, ferrosilicon ingots
are broken into coarse pieces by a jackhammer located in a closed area. Once broken, the
pieces of ferrosilicon are crushed and sieved before being stored in the loading hoppers.
At each of these stages, capture hoods are installed to prevent dust in the area.
THowever, during jackhammer crushing operations, dusts clouds still
occur despite the presence of the ventilation system in this area. These clouds are so
dense that they force the shutdown of operations while the cloud is dissipating, which
causes productivity losses in the sector. A measurement study has demonstrated that the
entire ventilation network in this sector only works at 80% of its nominal capacity. This
lack of capacity regularly causes ventilation problems on other equipment in the sector.
- Identify the cause of the decreased ventilation capacity in the crushing
Optimize the dust removal efficiency of the jackhammer area to eliminate dust
clouds generated during ingots breaking activities.
An audit of the entire ventilation network of the crushing sector was carried out. Based on
the information collected during this audit, a reverse engineering phase of the complete
ventilation network of the sector was carried out. This reverse engineering phase
identified the causes of the decreased ventilation capacity in different points of the
sector, including the ingots breaking area. The corrective measures necessary to restore
the ventilation flow rate in the sector as well as those needed to optimize the crushing
area ventilation could then be proposed.
At the end of this study, it was determined that the
ventilation flow rate of the ingots breaking area had to be multiplied by 3 to prevent dust
clouds formation. It also been determined that some modification of the ventilation duck
would be necessary in order to restore the ventilation flow rates in the rest of the
network since it has been poorly designed. In this context, a modification of the treated
distribution flows by dust collectors in this sector has been proposed. This new
distribution then made it possible to propose a layout of the duck network more adapted for
this area. Simple modifications of the ventilation hood, dust collectors and fans have also
been proposed to achieve the new ventilation flow target in the sector.