The objective of the Exxaro Grootegeluk Medupi expansion project is to provide 14,6-million tons of coal a year to State-owned power utility Eskom's Medupi power station. This will be achieved through the expansion of the current Grootegeluk opencast mine and the beneficiation of the resultant run-of-mine (ROM) material through two new processing circuits, Grootegeluk 7 and Grootegeluk 8.
The Grootegeluk Medupi project will start coal delivery by May 2012 and full commissioning will be complete during 2014/15. This will be achieved through an in-house project management methodology, as well as with the assistance of design consultants, project specialists and contractors. The capital cost of the project is R9,5-million.
The project entails a brownfield expansion of Exxaro's Grootegeluk mine. Coal will be mined from the existing opencast pit at an accelerated rate, with the mine's current production increasing from 19-million sales tons a year to 34-million sales tons a year.
The brownfield expansion requires new developments in mining processes, screening, beneficiation and the stockyard. The project will make use of new technology to enable delivery of high-quality product. These will include semimobile crushers and tippers, the dry screening of material smaller than 6 mm, large coal dense-medium separator (DMS) (larcodem) units and large cyclones.
The expansion will be mined with semimobile in-pit tip-and-crusher units supplied by the truck-and-loading operations. The tipping bins and crushers will be mobile units, used in the pit, and will move with the mine as it progresses forward.
The ROM coal will be screened through the coarse coal screens to remove material smaller than 40 mm, while material smaller than 4 mm will be screened out dry to be mixed directly into the final product.
Material bigger than 40 mm and smaller than 100 mm will be beneficiated in the larcodems, while material smaller than 40 mm will be beneficiated in the large cyclones.
The fines in the process water will be recovered in the thickener dams and dried in filter presses to be mixed into the final product. When water gets into contact with the coal, it will not be allowed into the environment. Polluted water will be kept in the integrated water loop circulation to be reused in the beneficiation processes.
The stockyard will accommodate about 430 000 t of coal. The coal will be stacked with two stackers and reclaimed with one reclaimer. The ROM stockpiles will be introduced between the mine, the plant and the discard stackers to support continuous production.
About 794 housing units are also being built to cater for the project team and the expanded workforce thereafter. Of this, approximately 250 houses will be completed by December 2010 and the balance, of 738, will be completed by November 2011.
The expansion is part of the 40-year coal supply agreement, at an average of 14,6-million tons a year, that Exxaro secured with Eskom to supply the utility's new Medupi power station, which is under construction near Lephalale, in Limpopo.
The construction phase has begun on most of the section projects in the mine, with these mainly being bulk earthworks, excavation and building foundations. Specialist contractors have been appointed to execute contracts according to the schedule and cost baseline. Most of the equipment in the plants has been procured by Exxaro to be issued as free issue items to the contractors to install.
Construction Projects Status and Forecast Completion Dates
The structural, mechanical, processes and piping (SMPP) for the ROM is in the design phase and is expected to be completed at the beginning of 2012. The semimobile tips are in the manufacturing phase and are forecast to be completed in the second quarter of 2011. The bulk earthworks and civil mining area, which is forecast for completion in the first quarter of 2011, and the main civil ROM area, which is expected to be completed in the fourth quarter of 2011, are both in the construction phase.
Meanwhile, the bulk earthworks plant area is forecasted for completion at the end of 2010, while the main civil wet plant and the SMPP wet plant, are both expected to be completed at the end of 2011. The main civil thickeners are forecast for completion at the end of 2011. All these project areas are already in the construction phases.
The main civil screening, which is expected to be completed by mid-2011, with the SMPP screening plant expected for completion at the end of 2011. The SMPP is in the manufacturing phase. The filter plant and the low-voltage (LV) and instrumentation are in the design phase and is expected to be completed at the end of 2010 and the beginning of 2011.
The site preparation and services relocation and the 33-kV distribution panel have been completed for the infrastructure works. However, the buildings are in the construction phase and are expected to be completed in the second quarter of 2011, as well as the 11-kV distribution, which is expected to be completed by mid-2011. Meanwhile, the plant workshop has entered the construction phase and is expected to be completed in the first half of 2011.
The progress for projects in the blending and load-out area, the LV and instrumentation is in the design phase, and is expected to be completed at the end of 2010. The SMPP blending and load-out area design is completed and manufacturing will begin in the first quarter of 2011. The stackers and reclaimers have moved into the manufacturing phase and are forecast for completion at the beginning of the third quarter of 2011. The manufacturing and construction phase are running simultaneously for the assizing plant structural, civils, mechanical, electrical, instrumentation and piping processes, which is forecast to be completed by the second quarter of 2011, while the bulk earthworks blending and load-out area is forecast to be completed at the end of the first quarter of 2011. The main civil contract for the blending and load-out area, which is forecast to be completed in the third quarter of 2011, have both entered into the construction phase.
Edited by: Shannon de Ryhove
Creamer Media Senior Deputy Editor Polity & Multimedia
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