1. Bioresource Engineering Research Group (BioERG), Department of Chemical Engineering, Cape Peninsula University of Technology, P.O. Box 652, Cape Town 8000, South Africa
2. Department of Chemical Engineering Technology, Doornfontein Campus, University of Johannesburg, P.O. Box 524, Auckland Park, Johannesburg 2006, South Africa
3. Academic Support Program for Engineering in Cape Town (ASPECT), Water Research Group, Department of Civil Engineering, University of Cape Town, Rondebosch, Cape Town 7700, South Africa