Weba Chute Systems & Solutions assists a mining operation in Mexico by conducting a thorough assessment on the functionality of existing chutes in the plant.

As part of a significant investment to improve its processing facilities and enable the recovery of 40% of the gold that currently sits in its tailings as waste, a mining operation in Mexico called in a leading transfer point and chute systems OEM to conduct a thorough assessment on the functionality of existing chutes in the plant.

Leveraging its in-depth knowledge of material behaviour in chute systems, Weba Chute Systems & Solutions was tasked with establishing the feasibility of introducing filtered tailings at a rate of 1200 tph onto the existing transfer system currently handling waste with a nominal size of 400 mm at a rate of 5000 tph.

Alwin Nienaber, technical director at the company, explains that while the intention is for the filtered tailings to be conveyed when the waste rock is available, it would still mean that the same chutes would need to function transferring completely different material.

“Optimally, one should be able to assess a working transfer chute handling the actual material, however in the case of a feasibility assessment this is not possible, and we therefore started with a review of the test work and studies prepared by independent qualified professional materials handling experts.

This was done by Weba Chute Systems & Solutions by calibrating the material conditions and behaviour using Discrete Element Method (DEM).

“Use of DEM allowing our technical team to model the interaction between individual particles and boundaries and in so doing, to accurately predict the bulk solids behaviour,” Nienaber says.

Access to DEM software allows engineers to predict bulk material flow patterns and flow rates as well as velocity patterns and dead zones within transfer system. It also provides accurate information on particle distribution in segregation and blending and the impact forces on particles and boundary surfaces, showing wear patterns.

Nienaber cautions that while many companies do have access to this sophisticated software, not inputting the relevant or correct data can render the output information inaccurate.

The feasibility assessment included the transfer of sedimentary dry tailings, sedimentary filter cake, Breccia dry tailings and Breccia filter cake. DEM modeling was done considering material on its own and conditions where blended material would be conveyed.

In total, there were four conveyor transfer points that had to be assessed. These included an inline transfer point, a 90  transfer point, a transfer from conveyor to radial spreader intermediate conveyor and then onto the spreader boom conveyor.