20.500.12556/RUL-154965 Removal of toxic metals from sewage sludge by EDTA and hydrodynamic cavitation and use of the sludge as fertilizer Sewage sludge (SS) is rich in plant nutrients, including P, N, and organic C, but often contains toxic metals (TMs), which hinders its potential use in agriculture. The efficiency of removal of TMs by washing with ethylenediamine tetraacetate (EDTA), in combination with hydrodynamic cavitation (HC) and the usability of washed sewage sludge as fertilizer were investigated. The environmental risk was assessed. During 8 wash batches an average 35, 68, 47 and 45 % of Pb, Zn, Cd and Cu, respectively, as well as 22 and 5 % Mn and Fe were removed from the SS. The process solutions and EDTA were recycled at a pH gradient of 12.5–2, which was achieved by adding quicklime (CaO) and then acidification by H$_2$SO$_4$, so that no wastewater was produced, only solid waste (ReSoil® method). The quality of the recycled process solutions (they remained unsaturated with salts) and the efficiency of the washing process were maintained across all batches. On average, 46 % of the EDTA was lost during the process and was replenished. The initial leachability of EDTA-mobilized Pb, Zn, Cu, Cr and Fe remaining in the washed SS increased 6-, 17-, 3-, 11- and 11-fold, respectively, but not to hazardous levels except for Zn. After washing, P and K remained in the SS, plant-available P increased 3.3-fold, while total N and C were reduced by 20.28 and 2.44 %, respectively. Washed SS was used as fertilizer in the pot experiment. The yield of Brassica juncea did not improve, the uptake of TMs by the plants and the leaching of TMs from the soil were minimal. Our study highlighted the drawbacks and potential feasibility of the new SS washing method. sewage sludge toxic metals EDTA hydrodynamic cavitation ReSoil® soil fertilization phosphorus blato iz čistilnih naprav toksične snovi toksične kovine hidrodinamična kavitacija čiščenje blata gnojilo true false true Angleški jezik Slovenski jezik Članek v reviji 2024-03-12 10:10:29 2024-03-12 10:10:29 2024-05-24 08:37:43 0000-00-00 00:00:00 2024 0 0 10 str. Vol. 923, art. 171444 2024 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 631.4 0048-9697 10.1016/j.scitotenv.2024.171444 188503043 1-s2.0-S0048969724015857-main.pdf 1-s2.0-S0048969724015857-main.pdf 1 883001BBA8FAED1F236D6F4571544C7F 034b2e4cd6fac194d07cb52c3c83162f68b5c355e7e3606d53186f2bc0fad837 9c15741d-e050-11ee-a296-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=181649 https://www.sciencedirect.com/science/article/pii/S0048969724015857 1 605ed4f5-e050-11ee-a296-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=181648 Biotehniška fakulteta Fakulteta za strojništvo 0 0 0