| dc.description.abstract | Electricity is an essential but limited resource in South Africa. Limited supply capacity and
growing demand cause electricity prices to increase rapidly, therefore, reducing electricity
consumption. Costs are critical within the mining sector. Demand-side management (DSM)
is an appealing and effective initiative to reduce electricity consumption and costs. Various
DSM initiatives have already been implemented on isolated components within gold ore
transportation systems. Implementing such initiatives on multiple gold ore transportation
systems in an integrated ore distribution network has, however, not yet been analysed,
despite the large cost-saving potential.
A gold-processing plant is usually supplied from multiple mineshafts and waste rock dumps
within an ore distribution network. Implementing DSM on a gold ore transportation system
can influence the ore distribution channels and the gold plant operation. This study focused
on implementing a DSM initiative on an integrated ore distribution network without
negatively influencing production. Electrical load management was recognised as the
primary opportunity to deliver feasible cost savings.
In-depth investigations were conducted on several mining processes, which can be
categorised as mining, ore transportation and gold-processing. Within the ore transportation
system, rock winders are identified as the largest electricity consumers, which is the
component that has to be optimised. Although load management potential may exist, it may
not be feasible for practical reasons. Simulations were developed to fully quantify the effect
of implementing load management on rock winders at multiple shafts and the effect on the
system as a whole. This study was implemented on two complex gold ore transportation systems as case studies.
Peak period load shifting of 3.1 MW and 1 MW, respectively, were achieved on average for
a single test week. This is equivalent to a total electricity cost saving of R1.1 million and
R380 000 per annum, respectively. If the results of this study are extrapolated to the rest of
the mining sector, the potential cost savings could amount to R37 million per annum.
Large electricity cost savings were achieved without affecting the overall production
negatively. Furthermore, implementing load management on an ore transportation system
improved the monitoring and control of the ore supply. This creates electrical load
management opportunities on gold-processing plants due to improved production planning
capability. | en_US |
