Metal Bioleaching from Anaerobic Sediments from Reconquista river Basin (Argentina) as potential Remediation Strategy

PORZIONATO, NATALIA; TUFO, ANA; CANDAL, ROBERTO; CURUTCHET, GUSTAVO

ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH

SPRINGER HEIDELBERG

Lugar: HEIDELBERG; Año: 2016

0944-1344

Anaerobic sediments of urban watercourses are subjected to industrial pollution and frequently tend to accumulate heavy metals. The biocatalyzed oxidation and reduction of sulphur compounds that occur within the sediment are key reactions that determine mobility of metalssuch as occurs in mine acidic drainage reactions. The aim of this work was to study the application of this processes using heap leaching technology for the remediation of anaerobic contaminated sediments from Reconquista River basin. The bioleaching potentiality for remediation was demonstrated through batch tests in shake flasks with different pulp densities of anaerobic sediment containing 338 mg Kg-1of Zn and 117 mg Kg-1 of Cu. Subsequently, bioleaching heap systems were compiled into columns of 12 cm high and 6 cm diameter, fitted with perlite to improve drainage. In order to assess the effect of elementary sulphur over the mobility of metals from the bioheap to the aqueous solution, increasing concentrations of elementary sulphur (1%, 2%, 5% w/w) were added. After 3 months of acidification generated by periodic watering, the extraction of 70% of the initial Zn and 43% of the initial Cu was achieved.Polluted sediments from waterways as Reconquista River should not be indiscriminately manipulated if acid drainage is possible. Remediation by a simple and economically viable strategy like heap leaching is feasible.