Micro-algal Systems for Carbon Capture, Metal and Energy Recovery using Mine Waters
March 202687 pages
Laboratory and pilot work on indigenous South African microalgae used to treat metal-bearing mine water while capturing carbon, with biomass profiling, bioenergy routes and a preliminary techno-economic assessment.
By Centre for Bioprocess Engineering Research, University of Cape Town| March 2026
A four-strain polyculture of microalgae isolated in the Mpumalanga and Gauteng coalfields held its growth and carbon uptake at five times the metal load of the reference acid mine drainage, and stayed viable and still removing metals at ten times that load. In 100 litre outdoor raceway ponds it remained stable and productive through normal weather variation, cut dissolved metal concentrations and left water meeting fit-for-purpose irrigation standards. Chromium, cadmium, iron and manganese concentrated most strongly into the biomass. Of the bioenergy routes assessed, hydrothermal liquefaction came out ahead because it takes wet biomass without drying and concentrates the recovered metals into a separate stream.
How it opens
In this project we aim to investigate the application of indigenous microalgal species, with potential for rapid carbon assimilation into biomass, with concomitant potential for the remediation of metal-contaminated mine water as part of the remediation of the coal waste legacy.
How it concludes
Description
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