A Novel Approach for Microbial Activity Assessment in Bioleaching. Towards to a Standardised Fast Starting up Protocol

Biohydrometallurgy is a proven industrial method for extracting base metals from sulfidic ores with low-grade content and as a pre-treatment of Au ores. The lack of study of biological aspects related with microbial activity assessment makes it difficult to control and monitor these processes; and t...

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Detalles Bibliográficos
Autores: Perdigones, Blanca, Ramírez del Amo, Pablo, Mazuelos Rojas, Alfonso
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2024
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/168491
Acceso en línea:https://hdl.handle.net/11441/168491
https://doi.org/10.1016/j.mineng.2024.109053
Access Level:acceso abierto
Palabra clave:Bacterial Activity
Bioleaching
Biooxidation
Dissolved Oxygen
Oxygen Uptake Rate
Descripción
Sumario:Biohydrometallurgy is a proven industrial method for extracting base metals from sulfidic ores with low-grade content and as a pre-treatment of Au ores. The lack of study of biological aspects related with microbial activity assessment makes it difficult to control and monitor these processes; and the multitude of experimental procedures described in the literature hinders cross-study comparisons among researchers. Experimental tools that allow a quick and reliable quantitative assessment of the iron oxidising capacity of the cells during the bioleaching process are needed. This work proposes monitoring microbial activity through a simple and reliable method based on the offline measurement of the Oxygen Uptake Rate (OUR). The methodology allows to quantify the microbial activity evolution of a growing culture under no-limiting conditions. By this methodology, the maximum potential bioleaching rate of the culture at any time is determined, assessing the occurrence of a biological or chemical limitation. The results obtained reveals that whether due to Fe2+ or O2 depletion, substrate availability significantly limits microbial activity. This aspect is key to assess a culture suitability for bioleaching bioreactor inoculation, preventing long lag phases. Furthermore, the methodology allows for quick disturbances correction, avoiding process shutdowns and enhances technological reliability of continuous bioleaching.