Phytoremediation and biogas: a comprehensive approach to water sustainability

Abstract

Phytoremediation of aquatic plants is a technology for the bioremediation of contaminated waters that is presented as an economical and effective alternative in the extraction of contaminants. Of the great diversity of Panamanian flora, Lemna Minor stands out for its capacity to retain heavy metals and as biomass for the generation of biogas. Due to this, a bio-treatment of wastewater is proposed for the mining industry, implementing phytoremediation to absorb the mercury (Hg) residues generated in its process and anaerobic co-digestion after the extraction of mercury for energy cogeneration. The bibliographic review on the mercury absorption capacity in Lemna Minor and the data collected in the laboratory allowed defining parameters, obtaining as results the reproduction rate of the plant PA=7.78 g/m^2/h , absorption rate of mercury per unit mass of Lemna C_Hglemna=0.28μg/(g h) and the yield for minimum methane production under heavy metal toxicity in Lemna, PBM=132 L/kg.
S Extreme conditions of mercury concentrations found in mining regions of Asia of 103 μg/L were considered in which Posada & Arroyave Maya, 2006, verified that under these conditions the reproduction rate of Lemna Minor is not affected. Obtaining an area necessary for the treatment of these conditions of 15.21 hectáreas y un subproducto para la cogeneración de la planta mediante la implementación de codigestión anaeróbica de 156 228 L/h biogás.