Feasibility of bioleaching combined with Fenton-like reaction to remove heavy metals from sewage sludge

• Published in: Bioresource technology Vol. 142; pp. 530 - 534
• Main Authors: Zhu, Yi, Zeng, Guangming, Zhang, Panyue, Zhang, Chang, Ren, Miaomiao, Zhang, Jiachao, Chen, Ming
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.08.2013; Elsevier
• Subjects: Applied sciences; Bacterial leaching; Bioleaching; Biological and medical sciences; Biotechnology; Cadmium; Exact sciences and technology; Feasibility; Feasibility Studies; Fenton-like reaction; Fundamental and applied biological sciences. Psychology; Heavy metal solubilization; Heavy metals; Hydrogen Peroxide - chemistry; Hydrogen-Ion Concentration; Lead (metal); Metals, Heavy - isolation & purification; Pollution; Sewage - chemistry; Sewage sludge; Sludge; Solubility; Wastes; China, People's Rep; Heavy metal solubilization; Fenton-like reaction; Bioleaching; Sewage sludge; Fenton reaction; Feasibility; Bacterial leaching; Solubilization; Heavy metal
• DOI: 10.1016/j.biortech.2013.05.070
• ISSN: 0960-8524

•Bioleaching combined with Fenton-like reaction was feasible for heavy metal removal.•Zn and Cd were efficiently solubilized within 5-day bioleaching.•Cu and Pb solubilization was effectively enhanced Fenton-like reaction.•Heavy metal solubilization depended on their forms in sludge. Feasibility of bioleaching combining with Fenton-like reaction to remove heavy metals from sewage sludge was investigated. After 5-day bioleaching, the sludge pH decreased from 6.95 to 2.50, which satisfied the acidic conditions for Fenton-like reaction. Meanwhile, more than 50% of sludge-borne heavy metals were dissolved except for Pb. The bioleached sludge was further oxidized with Fenton-like reaction, with an optimal H2O2 dosage of 5g/L, the Cu, Zn, Pb and Cd removal reached up to 75.3%, 72.6%, 34.5% and 65.4%, respectively, and the residual content of heavy metals in treated sludge meets the requirement of Disposal of Sludge from Municipal Wastewater Treatment Plant – Control Standards for Agricultural Use (CJ/T 309-2009) of China for A grade sludge. Bioleaching combined with Fenton-like reaction was the most effective method for heavy metal removal, compared with 15-day bioleaching and inorganic acid leaching with 10% H2SO4, 10% HCl and 10% HNO3.