Estudio experimental de la atenuación de la oxidación de un lodo pirítico mediante la adición de cenizas volantes

Abstract

The present Ph. D. Thesis examines the process that controls the oxidation attenuation of a pyrite-rich sludge from Iberian Pyrite Belt using fly ash from Los Barrios power station (S Spain). This study includes a fly ash leaching test and flow-through experiments with the pyritic sludge, to understand the behaviour of both materials separately under leaching conditions. Later, column experiments are presented to simulate the sludge oxidation and AMD production, and to evaluate the effect of fly ash presence on the aforementioned processes. Definitely, the addition of fly ash to a pyrite-rich sludge showed an improvement of the quality of the acid drainages and the development of mechanisms (iron coating and hardpan formation) that can prevent the ADM production. The extrapolation of these experiments to the field could suppose the decrease of the pollutant load that is transported through the fluvial systems until the Atlantic Ocean.