Site determination for artisanal rock carbonate processing using qualitative multifactor analysis – case studies: Malawi and South Africa

Abstract

A techno-economic assessment of rock carbonate deposits in Malawi and South Africa was conducted using a qualitative analytical approach. This was done to identify occurrences that were amenable to Portland cement production by artisanal to small-scale methods. First, geographic information system (GIS) software was used to capture sites or clusters of sites and chemical characteristics of natural carbonate deposits in the two countries. In addition to the geological setting and chemical composition, other factors plotted were nearness to transport and electric power infrastructure, surface water sources as well as areas or centres with high human population density. In Malawi, three targets for potential small-scale Portland cement production are identified at Mkamasa and Mwapu-Sere in the Northern Region and Songwe Hill in the Southern Region. This is out of 58 potential sites scattered around the country. For South Africa, a similar analysis reduces the 709 potential sites to four. These fall on the farms Wieduow in the Western Cape Province, Syferfontein and Rietfontein in the Limpopo Province and Rooikop in the Free State Province. The study has, in addition, revealed that there are also many deposits with very little chemical data, some of which may have better potential for exploitation.

Keywords:

• artisanal
• clinker
• criteria
• geographic information system (GIS)
• infrastructure
• labour-intensive
• limestone
• marble
• mineral deposit
• mineral processing
• multifactor
• natural rock carbonate
• Portland cement
• reconnaissance
• site selection
• stratigraphy

ACKNOWLEDGEMENTS

The authors thank Dr Solomon Tesfamichael of the Department of Geography, Environmental and Energy Studies, Dr Walter Musakwa and Mr Aurobindo Ogra of the Department of Urban and Rural Planning, University of Johannesburg, for their assistance with the use of GIS software. The financial assistance received from the University of Johannesburg through the Mineral Processing and Technology Research Centre and the National Research Foundation (NRF) as incentive to NRF-rated professionals is acknowledged.

DISCLOSURE STATEMENT

No potential conflict of interest was reported by the authors.