Coal and heavy minerals mining company Exxaro Resources’ Limpopo-based Grootegeluk Medupi Expansion Project (GMEP) is 97% complete, with total project costs still estimated at R10.2-billion, according to the company’s 2013 Integrated Report.

The GMEP is a brownfield expansion project and forms part of Exxaro’s 40-year coal supply agreement with State-owned power utility Eskom. At an average of 14.6-million tons a year, Exxaro secured the contract with Eskom to supply the utility’s new Medupi power station, which is currently under construction near Lephalale, in Limpopo.

The company will take run-of-mine (RoM) output to about 66-million tons a year – from 38-million tons – and will double its production of power station coal to 30-million tons a year, states the report.

Further, Exxaro will continue ramp-up of the GMEP. Coal deliveries restarted in June, this year. Exxaro noted in its interim results for the six months ended June 30, that optimisation and performance testing is in progress until full ramp-up.

Coal supply ramp-up at the GMEP started during the first half of 2013 and is expected to continue into the second half of 2016.

Exxaro adds that the Grootegeluk discards backfill project has progressed well, with Phase 1 completed in 2013, commissioning scheduled for the second half of this year and Phase 2 planned for completion and commissioning in 2017.

Meanwhile, Eskom’s Medupi power station in July commissioned a PA299-2100/50+50 spreader supplied by mining equipment manufacturer Sandvik for the GMEP to supply coal to the Medupi power station.

This follows Exxaro’s requirement for a spreader that can deal with high volumes of discard material for backfill and reintegration into the mined pit, as the discard rate is expected to reach up to 7 670 t/h at full production.

Operational Performance
While Eskom has already started receiving coal from Exxaro’s Grootegeluk mine, located alongside the Medupi project, in July, it was forced to make a R2.5-billion provision to Exxaro, as it was unable to consume coal at the power generation project, which was running behind schedule.

Mining Weekly reported in August that Exxaro would have delivered 6.2-million tons of coal to Medupi from its GMEP. The latest settlement, however, requires the project to deliver half that amount to Medupi.

Further, Exxaro announced in September that its R16-billion five-year capital expenditure plan involves additional expansion at Grootegeluk, the development of the new Thabametsi coal mine’s north and south phases, augmentations to the semi-coke and market-coke value-add plants, and a 600 MW Phase 1 coal-fired power plant, in partnership with an independent power producer.

While Grootegeluk’s metallurgical coal production increased by 214 000 t, or 23%, in the first half of 2014, mainly as a result of an initiative to fill an increased number of trains allocated by parastatal Transnet Freight Rail, with sales to steel producer ArcelorMittal South Africa increasing by 11 000 t, or 2%, for the first half year of the year, the company notes that its commercial mines’ power station coal production was 311 000 t, or 3%, lower than the first half year of 2013.

The company notes that this reflects “a cut-back in production at Grootegeluk as a result of the lower burn rate at Matimba power station, owing to shuts on units and stacker-reclaimer problems”.

Mining Prospects
Grootegeluk has a resource base of about 4.7-billion tons and about 50 years life-of-mine at current rates, the company noted in a September media presentation. However, it added at the presentation that its brownfield expansion for the upper pit would involve the GG6 plant expansion. This involves an increased rate of pit liberation, conversion of the GG2 plant to enable full double-stage washing, and an additional SSCC or export coal of 1.5-million tons. However, changes are required to the load-out station.

For the bottom pit summary, Exxaro noted that implementation of the GG6 expansion and Bench 5 liberation to supply Medupi enables pit bottom liberation of B9B/11/13. Bench 13 is suitable as metallurgical RoM feed, while a full-scale mining test was successfully completed.

Meanwhile, the GG9/GG10 expansions would supplement the GG4/GG5 metallurgical coal production, while the product would be transported and loaded through the existing SSCC load-out facility and the future load-out facility.

Exxaro’s Waterberg development strategy further entails sustaining capital from 2015 to 2019, which includes a truck replacement strategy, shovel replacement strategy, stacker and reclaimer strategies, as well as a slimes handling strategy.

Other strategies include internal enablers, such as the in-pit crusher and conveyor system to improve ex-pit rate, a new load-out station, with a rail upgrade to 26 t for each axle, as well as a 200-wagon train.

The rapid multiproduct load-out station would be linked to the GG10 expansion and could provide for the Thabametsi mine export coal, Exxaro noted.

External enablers for development include Transnet Freight Rail’s ramp-up, Total Coal South Africa entitlement, as well as allocation from the Mokolo and Crocodile Water Augmentation Project (MCWAP).

The MCWAP, implemented by the Trans-Caledon Tunnel Authority, involves the phased construction of two main bulk raw water transfer systems, as well as associated infrastructure to meet demand from the new power station, mines, and domestic consumers, in the Lephalale area.