Metal bioleaching from anarobic sediments from Reconquista -River basin (Argentina) as a potential remediation strategy

PORZIONATO NATALIA; ANA TUFO; CANDAL ROBERTO; CURUTCHET GUSTAVO

ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH

SPRINGER HEIDELBERG

Año: 2016

0944-1344

Anaerobic sediments of urban watercourses aresubjected to industrial pollution and frequently tend to accumulateheavy metals. The biocatalyzed oxidation and reductionof sulphur compounds that occur within the sediment arekey reactions that determine mobility of metals such as thatoccurred in mine acidic drainage reactions. The aim of thiswork was to study the application of these processes usingheap leaching technology for the remediation of anaerobiccontaminated sediments from Reconquista River basin. Thebioleaching potentiality for remediation was demonstratedthrough batch tests in shake flasks with different pulp densitiesof anaerobic sediment containing 338 mg kg−1 of Zn and117 mg kg−1 of Cu. Subsequently, bioleaching heap systemswere compiled into columns of 12-cm height and 6-cm diameter,fitted with perlite to improve drainage. In order to assessthe effect of elementary sulphur over the mobility of metalsfrom the bioheap to the aqueous solution, increasingconcentrations of elementary sulphur (1, 2, 5 % w/w) wereadded. After 3 months of acidification generated by periodicwatering, the extraction of 70 % of the initial Zn and 43 % ofthe initial Cu was achieved. Polluted sediments from waterwaysas Reconquista River should not be indiscriminatelymanipulated if acid drainage is possible. Remediation by asimple and economically viable strategy like heap leachingis feasible.