Aplicación del sistema de remediación pasivo Sustrato Alcalino Disperso (DAS) para tratar lixiviados de fosfoyesos altamente ácidos y contaminantes

  1. Ricardo Millán-Becerro 1
  2. Carlos R. Cánovas 1
  3. Francisco Macías 1
  4. Rafael Pérez-López 1
  5. José Miguel Nieto 1
  1. 1 Departamento de Ciencias de la Tierra y Centro de Investigación en Recursos Naturales, Salud y Medio Ambiente (RENSMA). Universidad de Huelva. Campus “El Carmen” s/n, 21071, Huelva (España)
Journal:
Geogaceta

ISSN: 0213-683X

Year of publication: 2021

Issue Title: Comunicaciones presentadas en la LXX Sesión Científica / SGE-Virtual, 28 de mayo de 2021

Issue: 70

Pages: 31-34

Type: Article

More publications in: Geogaceta

Abstract

This work studies the feasibility of the Dispersed Alkaline Substrate (DAS) technology for the passive treatment of highly acidic and polluted effluents from the phosphogypsum stack located on the Tinto river marsh soils (Huelva, SW Spain). The study consists of flowing the acidic water through a column filled with a mixture of an alkaline reagent (i.e. Ca(OH)2 ) scattered on an inert matrix (i.e. wood chips) capable of raising the pH of the leachate and precipitating the dissolved pollutants. The Ca(OH)2 -DAS treatment system achieved the total removal of PO4 , F, Fe, Zn, Al, Cr, U and As from the solutions. The precipitation of brushite [CaHPO4 ∙2H2 O] and gypsum [CaSO4 ∙2H2 O] seems to be the main mechanism responsible for the removal of contaminants. The solids collected from the DAS column were subjected to the EU EN 12457-2 leaching test for their classification and management according to their hazardousness. Some of these solids could be classified as hazardous wastes due to the high release of SO4 . This study may contribute to the design of an effective and sustainable treatment of leachates from the fertilizer industry