Page 11 - Energize June 2021

NEWS

in the supply chain, and how these
livelihoods could be affected by standards Unique projects call for unique solutions
imposed by Europe.
“The intent of this initiative is to B Switchgear Solutions was recently awarded a contract to design, manufacture,
optimise positive impacts generated and supply four containerised substations for the Gbeni site of Sierra Rutile’s
by the way that minerals are sourced,” Jmining operations.
said Lisl Pullinger, principal consultant - This was a unique project since the containers each had to house a MV/LV dry type
ESG at SRK Consulting. “How we define transformer and electrical switchgear. This containerised equipment had been put onto a
responsible sourcing forces us to ask the skid and these skids were built to be movable around the mining site.
difficult questions about how sourcing The substations/skids were broken up into four: Two booster skids/substations, one
standards could have unintended effects mining in-pit skid/substation and a scrubber skid/substation.
on livelihoods in Africa. If livelihoods The containers for the booster skid and mining in-pit were made into 7 m lengths
are undermined, for instance, are those and were split at the mid-point by a partition wall, so that one side housed the dry-type
standards really responsible?” transformer, and the other side housed the LV panels.
Pullinger highlighted that the process The booster substations were also 7 m long, and each housed an 800 kVA dry type
is even more relevant in the context of transformer on the one side of the container and the LV panels on the other side.
economic disruption due to the Covid-19 The LV section housed the MCC, which consisted of an incomer rated at 1250 A, which fed
pandemic, where the inequalities two 260 kW free standing variable speed drives (VSDs) in the container. These VSDs were used
between regions have been brought into for the slurry pumps on the skid. The LV section of the container housed a 250 A PFC panel as
stark contrast.
well, which was fed from the MCC.
Engagement vital The mobile mining unit/mining in-pit substation was also 7 m long and housed a 1600
One of SRK Consulting’s functions will kVA dry type transformer on the one side of the container. The LV section housed the MCC,
which consisted of an incomer rated at 2000 A, which fed two 160 kW soft starters, as well as
be to facilitate the input of a forum of a 355 kW free standing VSD, which is used for the gravel pump. The LV section of the container
stakeholders from around sub-Saharan housed a 400A PFC panel, also fed from the MCC.
Africa next year, said Van Zyl. The scrubber substation was initially a 12 m container, but due to skid restraints, was
“This process should have wide cut into half, thus becoming two containers, with one feeding the MCC panels in the other
interest and engagement, allowing container via an encapsulated busbar system.
organisations to flag possible unintended The set up was the same as the previous containers. One of the 6 m containers was
consequences of future European divided to accommodate the 2000 kVA dry type transformer which fed the LV panel with an
directives aimed at responsible sourcing encapsulated bus-bar system. The LV section housed the MCC which featured a 2500A incomer.
– before those directives are applied,” The panel consisted of 15 DOL starters, plus a few feeders.
he said. “This recognises that there are The second incomer had a second incomer rated at 2500A as well, which was fed from the
many national standards to which mines first container. This container housed a 200 kW wall mounted VSD for the water booster pump,
already comply, which do not need to be two 260 kW VSDs for the trommel underflow pump, and two 330 kW VSDs for the scrubber
reinvented. These standards have been trommel. The LV section of the container housed a 400A PFC panel, also fed from the MCC.
developed following ongoing, pro-active
engagement between stakeholders.” Contact JB Switchgear, Tel 011 027-5804, info@jbswitchgear.co.za
He highlighted that there was potential
for significant disruption to supply chains
originating in Africa, if any directive
happened to include well-intentioned
requirements that were difficult or
impossible to comply with.
“We expect the mining sector to be
enthusiastic about participating in these
consultations, as it is both a good risk
management strategy and an effective
way of providing price support for acting
responsibly,” he said. “Those responsible
miners – who have chosen to embrace
both the opportunities and challenges of
responsible mining – can only gain from
well-considered responsible sourcing
standards being applied to every player in
the sector.”

Contact SRK, Tel 011 441-1111,
johannesburg@srk.co.za,
www.srk.co.za

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