Effect of ferrous iron loading on dewaterability, heavy metal removal and bacterial community of digested sludge by Acidithiobacillus ferrooxidans

Acidithiobacillus ferrooxidans ILS-2 was adapted in digested sludge and used to treat for dewaterability improvement. Results showed that increasing ferrous iron loading increased dewaterability, but the inoculation of bioleaching strain had little effect on compared controls without strain. The total extracellular polymeric substances (EPS) contents sludges with treatment were similar except at 10% (on solids) where EPS higher treatment. However, 48 h a notable removal heavy metals, such as Mn, Ni Zn, especially high loadings iron. In presence A. ferrooxidans, Ni, Mn Zn reached 93%, 88% 80%, respectively, 21%. sequencing 16S rRNA genes indicated 15% 21% relative abundance Acidithiobacillus, Acidocella (with ferrooxidans) Carboxylicivirga (without decreased Pseudomonas Acinetobacter after This study enhanced understanding correlations between sludge, metal bacterial communities.