Click on image to view larger version.



Fig. 4. Values for (a) pH, (b) redox potential (ORP), and (c) sulfate concentration at different sludge solids concentrations during microbial leaching with Acidithiobacillus thiooxidans MET. Symbols: •, 20 g L-1; {triangledown}, 50 g L-1; {blacksquare}, 90 g L-1; {diamond}, 130 g L-1.