Thought led thickening
McLanahan Corporation reviews different types of
thickeners and highlights that success of a thickening
system requires that a sound effort is made to understand
the tailings
ailings are not the easiest or cleanest
thing to deal with. However, we mine
because the materials we work with have
value, and as concentration and refinement
processes reduce these values to smaller
volumes, we discard the barren or low value
materials and focus more on the valuable
materials – gold, clean coal, competent
aggregate, etc.
The best way for producers to deal with
tailings is to answer the question: What do you
envision as the long-term solution? This will
often depend on the characteristics of the
tailings. If the tailings are comprised of
relatively coarse particles (+38 microns) then
the answer may be as simple as pumping them
to cyclones for recovery and dam building, with
the fine cyclone overflow being impounded
behind the dam. This method has, for many
decades, been employed to both collect/store
tailings, as well as to clarify water for reuse in
the process plant. Make sure it is a long-term
fix and not a short term fix. Most short-term
fixes don’t fix the problem and create more
downtime and loss of profits.
What could possibly be cheaper than to dig
a hole or build a dam and create a space for
the waste generated by processing activities?
Two of the most frequent problems brought up
are “we don’t have enough screens” and “our
ponds are running out of space.” Dredging a
pond to create more room for incoming tailings
can become very costly. An additional pond
T
could be opened, but space and/or permitting
might not be possible. Additionally, there is the
potential to cover reserves that you may need
and the loss of process water due to
evaporation or percolation.
Besides the costs associated with the pond
solution, there are also risks. Risks that
include placing people on or near the water
while maintaining the pond or
building higher dam structures.
Impoundment failure is anot