Applicability of phytoremediation in waste sludge stabilization

In this study, improvement and rehabilitation potential of the wastewater treatment sludge obtained from Adana West Wastewater Treatment Plant by Aptenia Cordifolia, Carpobrotus Edulis and B.Delagoensis Tubiflorum species and investigation of the potential use of the sludge in plant cultivation as growth medium were aimed. The study includes three different growth media, as (1) Soil, (2) Diatomite + stabilized sludge and (3) Basaltic tuff + stabilized sludge. The experimental period was sustained 90 days and irrigation was carried out by C1S1 class irrigation water. Residual heavy metal concentrations in growth medium and heavy metal accumulations in the tissues of the plants, as roots and stems/leaves, were observed. Highest removal rates of heavy metals were observed for Cr, Fe, Ni, Mn by B. Tubiflorum specie as 91.13%, 80.55%, 88.01% and 62.27% in the diatomite medium, respectively. The highest removals of Cu and Pb in the same medium were observed as 45.19% and 73.41% by C. Edulis specie, respectively. Cr, Cu, Pb, Fe and Ni removal rates in basaltic medium were observed to be highest in the sets of A. Cordifolia, as 82.01, 48.71%, 51.89%, 66.16% and 72.58%, respectively. In the same media highest Mn removal rate was observed by C. Edulis, as 59.33%. The results of the study implies that, because it was observed that the stabilized sludge addition to tuff medium apparently enhances growth rates of the plants, sludge may be used in ornamental plant cultivation sector, whereas the study also implies that heavy metal uptake can be improved by addition of diatomite, which can be abundantly found in Turkey, to the growth medium. Keywords : Phytoremediation, Aptenia Cordifolia, Carpobrotus Edulis, B. Delagoensis Tubiflorum, Heavy metal accumulation