Metal bioleaching from anaerobic sediments from Reconquista River basin (Argentina) as a potential remediation strategy.
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 metals such as that occurred in mine acidic drainage reactions. The aim of this work was to study the application of these 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-1of Cu. Subsequently, bioleaching heap systems were compiled into columns of 12-cm height 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.
Instituto de Investigación e Ingeniería Ambiental, and Escuela de Ciencia y Tecnología, Universidad Nacional de San Martín, Campus Miguelete 25 de Mayo y Francia, San Martín, Provincia de Buenos Aires, Argentina.
Natalia
N
Porzionato
Instituto de Investigación e Ingeniería Ambiental, and Escuela de Ciencia y Tecnología, Universidad Nacional de San Martín, Campus Miguelete 25 de Mayo y Francia, San Martín, Provincia de Buenos Aires, Argentina.
Ana
A
Tufo
Instituto de Investigación e Ingeniería Ambiental, and Escuela de Ciencia y Tecnología, Universidad Nacional de San Martín, Campus Miguelete 25 de Mayo y Francia, San Martín, Provincia de Buenos Aires, Argentina.|Consejo Nacional de Investigaciones Científicas y Técnicas, Rivadavia 1917, Buenos Aires, Argentina.|Instituto de Química Física de Materiales, Medio Ambiente y Energía, CONICET-Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires, Argentina.
Roberto
R
Candal
Instituto de Investigación e Ingeniería Ambiental, and Escuela de Ciencia y Tecnología, Universidad Nacional de San Martín, Campus Miguelete 25 de Mayo y Francia, San Martín, Provincia de Buenos Aires, Argentina. gcurut@gmail.com.|Consejo Nacional de Investigaciones Científicas y Técnicas, Rivadavia 1917, Buenos Aires, Argentina. gcurut@gmail.com.
Gustavo
G
Curutchet
D000693:Anaerobiosis; D001118:Argentina; D001673:Biodegradation, Environmental; D052918:Environmental Restoration and Remediation / Q000379:methods*; D019015:Geologic Sediments / Q000032:analysis*; D019216:Metals, Heavy / Q000032:analysis / Q000378:metabolism*; D045483:Rivers / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism*
D019216:Metals, Heavy; D014874:Water Pollutants, Chemical
Anaerobic polluted sediments; Bioheap leaching; Heavy metals; Reconquista basin; Remediation strategy; Sulphur-oxidizing bacteria