Alternativas potenciales del Biotratamiento de aguas acidas en el cierre de operaciones mineras: Aerobio o Anaeborio
Abstract
Una vez que las instalaciones mineras llegan al final de su ciclo productivo es difícil mantener el tratamiento de las aguas ácidas por métodos clásicos (con adición de sustancias alcalinas y consumo de energía) debido a su elevado costo de tratamiento, por lo que existe la necesidad de buscar la remediación de estas aguas a través del empleo de tecnologías limpias y económicas que incluyen plantas y microorganismos (tecnologías emergentes) a fin de reducir o eliminar el riesgo de contaminación ambiental del medio físico circundante. Los drenajes que se generan en instalaciones mineras abandonadas o al final de la vida operativa de una mina, pueden constituir importantes fuentes de contaminación y generar una serie de alteraciones medioambientales, como: cambio de la calidad de las aguas superficiales y subterráneas, perturbación de habitats y ecosistemas acuáticos, entre otros. En este trabajo se describirá la filosofía del funcionamiento de los Humedales (wetlands) Aerobios o Anaerobios y la metodología para el dimensionado de un sistema de tratamiento pasivo mediante humedales. Esta tecnología aporta posibilidades para inmovilizar los metales en formas no-biodisponibles, utilizando dispositivos diseñados para este fin y convertir los iones metálicos tóxicos a formas químicas más inocuas y estables. También se identificará con mayor detalle los parámetros más determinantes en el diseño y dimensionado de dispositivos de tratamiento pasivo, como: las características del agua, el área o superficie, la geometría del dispositivo, la profundidad de las celdas, el tiempo de retención hidráulica y la composición de los substratos. Para lograr un funcionamiento eficaz del sistema de tratamiento, se suele utilizar una combinación de distintos dispositivos de tratamiento, dispuestos en forma secuencial, incluyendo unidades de pre-tratamiento, tratamiento y post-tratamiento
Once mining facilities reach the end of their productive cycle, it becomes difficult to maintain the treatment of acid waters using conventional methods (with the addition of alkaline substances and energy consumption) due to the high treatment costs. Therefore, there is a need to seek remediation of these waters through the use of clean and low-cost technologies that include plants and microorganisms (emerging technologies), in order to reduce or eliminate the risk of environmental contamination of the surrounding physical environment. The drainage generated in abandoned mining facilities or at the end of a mine's operational life can constitute significant sources of contamination and cause a series of environmental impacts, such as changes in the quality of surface and groundwater, disturbance of aquatic habitats and ecosystems, among others. This work describes the operating principles of aerobic and anaerobic wetlands and the methodology for sizing a passive treatment system using wetlands. This technology provides opportunities to immobilize metals in non-bioavailable forms using devices designed for this purpose, and to convert toxic metal ions into more benign and stable chemical forms. The most critical parameters for the design and sizing of passive treatment systems will also be identified in greater detail, including water characteristics, area or surface, system geometry, cell depth, hydraulic retention time, and substrate composition. To achieve effective operation of the treatment system, a combination of different treatment units is typically used, arranged sequentially and including pre-treatment, treatment, and post-treatment stages.
Once mining facilities reach the end of their productive cycle, it becomes difficult to maintain the treatment of acid waters using conventional methods (with the addition of alkaline substances and energy consumption) due to the high treatment costs. Therefore, there is a need to seek remediation of these waters through the use of clean and low-cost technologies that include plants and microorganisms (emerging technologies), in order to reduce or eliminate the risk of environmental contamination of the surrounding physical environment. The drainage generated in abandoned mining facilities or at the end of a mine's operational life can constitute significant sources of contamination and cause a series of environmental impacts, such as changes in the quality of surface and groundwater, disturbance of aquatic habitats and ecosystems, among others. This work describes the operating principles of aerobic and anaerobic wetlands and the methodology for sizing a passive treatment system using wetlands. This technology provides opportunities to immobilize metals in non-bioavailable forms using devices designed for this purpose, and to convert toxic metal ions into more benign and stable chemical forms. The most critical parameters for the design and sizing of passive treatment systems will also be identified in greater detail, including water characteristics, area or surface, system geometry, cell depth, hydraulic retention time, and substrate composition. To achieve effective operation of the treatment system, a combination of different treatment units is typically used, arranged sequentially and including pre-treatment, treatment, and post-treatment stages.
Description
Vol. 10, No. 2