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Odpadno blato iz čistilnih naprav (ČN) ima zaradi velike hranilne vrednosti potencial za uporabo v kmetijstvu, vendar je pogosto onesnaženo s potencialno strupenimi kovinami (PSK). V raziskavi smo preverili ali ReSoil® tehnologija, ki temelji na uporabi EDTA (50, 70 in 100 mmol l$^{-1}$ omogoča učinkovito odstranjevanje PSK iz odpadnega blata, vzetega po aerobni (blato1) in anaerobni (blato2) biološki obdelavi. Največji delež odstranitve Pb smo dosegli v blatu1 (do 60 %), največji delež odstranitve Zn in Cu pa v blatu2 (do 55 in 29 %). Vsebnost hranil se po remediaciji ni bistveno spremenila, le vsebnost dostopnega fosforja se je v blatu2 po remediaciji do 1,7-krat zmanjšala, vendar je še vedno ostala velika (489- 510 mg 100$^{-1}$ g$^{-1}$). Po remediaciji so bile koncentracije v izpirkih za vse kovine, razen za Zn, pod mejo za nenevarne snovi. Za dokazovanje možnosti recikliranja procesnih raztopin in EDTA smo blato2 oprali s 50 mmol l$^{-1}$ pralno raztopino v seriji 5 zaporednih remediacij in pri tem v povprečju odstranili 28 % Pb, 48 % Zn, 35 % Cu, 30 % Mn in 10 % Fe. ReSoil® tehnologija sicer omogoča odstranjevanje PSK iz blata in pri tem ohrani njegovo hranilno vrednost, vendar je učinkovitost tehnologije odvisna od postopkov obdelave blata na ČN. Sewage sludge has the potential to be used as a fertilizer in agriculture because of its high nutritional value, but it is often contaminated with toxic metals (TM). This study investigated whether ReSoil® technology, based on the use of EDTA (50, 70, and 100 mmol l$^{-1}$), efficiently removes TM from sewage sludge collected after aerobic (blato1) and anaerobic (blato2) treatment. The highest removal efficiency of Pb was achieved in blato1 (up to 60 %) and of Zn and Cu in blato2 (up to 55 and 29 %, respectively). The content of nutrients did not change significantly after remediation, only available phosphorus decreased up to 1.7-times in blato2, but its content remained high (489-510 mg 100$^{-1}$ g$^{-1}$). After remediation, the concentration of all metals, except Zn, in the leachates was below the limit for non-hazardous substances. To demonstrate the possibility of recycling process solutions and EDTA, blato2 was washed in 5 consecutive batches with 50 mmol l$^{-1}$ washing solution, removing on average 28 % Pb, 48 % Zn, 35 % Cu, 30 % Mn, and 10 % Fe. ReSoil® technology removes metals from sludge and preserves its nutritional value. However, the efficiency of the technology depends on the treatment process used in the wastewater treatment plant. Nasl. z nasl. zaslona. Opis vira z dne 9. 1. 2023. Bibliografija: str. 8-10. Izvleček ; Abstract: Removal of potentially toxic metals from sewage sludge using EDTA.