Abstract:
Vein graphite mining is more often carried out by underground mining in
Sri Lanka due to its mode of occurrence. Bogala underground mine is one of the
major graphite mines in the country, where overhand cut-and-fill mining method is
used for the extraction of graphite since the ore bodies are steeply dipping, with
considerable vertical extent and clear and stable ore boundaries. According to the
standard practices at the mine, ectraction is carried out at the stope by blasting of
both rock and graphite vein in the exposed face, followed by hand sorting to collect
graphite. Blasting the host rock and veins are carried out separately. Waste rock
generated is used to fill the lower bench. Simultaneously, stope support is carried
out and the working platform prepared. In this practice one cycle extends for four
shifts and the research was launched with the objective of improving stope
productivity by reducing the cycle time. In the proposed methodology, blasting of
the face (graphite vein and rock) was carried out simultaneously resulting in the
reduction of cycle time to two shifts. Therefore, in the research carried out, with the
proposed alternative stope technique followed by froth flotation relevant
performance indicators or parameters of productivity, cost and safety were
analysed.
