Abstract

Dewatered tailings can be among the most difficult flowing bulks solids found in the mining industry. Understanding the scientific principles that guide good bin and feeder design for difficult flowing cohesive materials, such as dewatered tailings, is key to knowing how to design appropriate storage and feed system capable of reliably handling these materials.

Starting in the 1980s, Kamengo led an extensive research program examining why bins plug, in particular when handling difficult flowing cohesive and large particle materials. What the researchers discovered surprised them.

This presentation will review the key findings from Kamengo’s research. In particular, it will review the three root causes of intermittent discharge and bin plugging, which are:

1) incorrect bin geometry;

2) compaction of the stored material by the discharge feeder; and,

3) uneven withdrawal of material by the discharge feeder.

The presentation will use three case studies to illustrate how the outcomes of Kamengo’s research were applied in the design of new equipment as well as the retrofit of equipment suffering from chronic plugging, including equipment handling dewatered tailings. The presentation will look at the design of two tall truck-load out bins handling nickel laterite dewatered tailings at a mine in the South Pacific. The presentation will also look at lessons learned from other parts of the mine handling cohesive materials, such as ore concentrate filter cake. In particular, the presentation will look at the flow properties and the retrofit of metering bins handling wet cobalt-hydroxide filter cake at a mine in the Democratic Republic of the Congo. Finally, the presentation will use the example of two self-unloading ships to discuss the design implications of storing and reclaiming cohesive materials, such as dewatered tailings, from long piles or very large silos.