Cr, Ni, and Zn removal from landfill leachate using vertical flow wetlands planted with Typha domingensis and Canna indica

MAINE, MARÍA ALEJANDRA; HADAD, HERNÁN RICARDO; CAMAÑO SILVESTRINI, NAHUEL ERNESTO; NOCETTI, EMANUEL; SANCHEZ, GABRIELA CRISTINA; CAMPAGNOLI, MARCELO ABEL

INTERNATIONAL JOURNAL OF PHYTOREMEDIATION

TAYLOR & FRANCIS INC

Año: 2021 p. 1 - 10

1522-6514

Chromium (Cr), Nickel (Ni), and zinc (Zn) removal from landfill leachate using mesocosm-scale verticalflow wetlands, the effect of recirculation, and the ability of macrophytes to retain metalswere evaluated. Wetlands were filled with coarse sand and light expanded clay aggregates andplanted with Typha domingensis or Canna indica. Wetlands were operated using intermittent loading,with and without recirculation. Raw leachate was diluted and spiked with metals to reach thefollowing concentrations: 0.2mg L1 Cr , 0.2mg L1 Ni, and0.2mg L1 Zn and 1.0mg L1 Cr,1.0mg L1 Ni, and 1.0mg L1 Zn. Wetlands planted with T. domingensis presented higher metalremoval than those planted with C. indica. Recirculation enhanced metal removal efficiencies significantly,being for T. domingensis/C. indica: 60/54, 49/47, 61/47% for Cr, Ni, and Zn at 0.2mg L1,and 80/71, 76/62, 73/59% for Cr, Ni, and Zn at 1.0mg L1, respectively. Metals were efficientlyretained by macrophytes. Plant biomass and metal concentrations in roots were significantlyhigher than in shoots. Scanning electron microscopy and X-ray microanalysis showed that metalswere absorbed by internal root tissues. A hybrid wetland planted with T. domingensis may beimplemented to improve not only metal but also chemical oxygen demand and total nitrogenremovals.