Macrophyte growth in a pilot-scale constructed wetland for industrial wastewater treatment

• Published in: Chemosphere (Oxford) 2006-06, Vol.63 (10), p.1744-1753
• Main Authors: Hadad, H.R., Maine, M.A., Bonetto, C.A.
• Format: Article
• Language: English
• Subjects: Applied sciences; bioaccumulation; Biodegradation, Environmental; Biological and medical sciences; Biological treatment of waters; Biotechnology; chromium; Chromium - analysis; Chromium - metabolism; Chromium - toxicity; constructed wetlands; Environment and pollution; Exact sciences and technology; Freshwater; Fundamental and applied biological sciences. Psychology; Hydrogen-Ion Concentration; Industrial applications and implications. Economical aspects; industrial effluents; Industrial Waste; Industrial wastewaters; leaves; Macrophytes; Magnoliopsida - drug effects; Magnoliopsida - growth & development; Magnoliopsida - metabolism; Metallurgy; nickel; Nickel - analysis; Nickel - metabolism; Nickel - toxicity; Phosphorus - analysis; Pilot-scale wetland; Plant Leaves - drug effects; Plant Leaves - growth & development; Plant Leaves - metabolism; Plant Roots - drug effects; Plant Roots - growth & development; Plant Roots - metabolism; Pollution; roots; sediments; Typha domingensis; Waste Disposal, Fluid - methods; Wastewater; wastewater treatment; Wastewaters; Water Pollutants, Chemical - analysis; Water Pollutants, Chemical - metabolism; Water Pollutants, Chemical - toxicity; Water Purification - methods; Water treatment and pollution; zinc; Zinc - analysis; Zinc - metabolism; Zinc - toxicity
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2005.09.014

A pilot-scale wetland was constructed to assess the feasibility of treating the wastewater from a tool industry in Santo Tomé, Santa Fe, Argentina. The wastewater had high conductivity and pH, and contained Cr, Ni and Zn. This paper describes the growth of vegetation in the experimental wetland and the nutrient and metal removal. The wetland was 6 × 3 × 0.4 m. Water discharge was 1000 l d −1 and residence time was 7 d. After the wetland was rendered impermeable, macrophytes from Middle Paraná River floodplain were transplanted. Influent and effluent quality was analyzed every 15 d. TP, Cr, Ni and Zn concentrations in leaves, roots and sediment (inlet and outlet) were measured monthly. Cover and biomass of predominant species were estimated. Also, greenhouse experiments were carried out to measure the effects of conductivity and pH on floating species. The variables measured in the influent were significantly higher than those in the effluent, except for HCO 3 - and NH 4 + . TP and metal concentrations in sediment at the inlet were significantly higher than those at the outlet. Conductivity and pH of the incoming wastewater were toxic for the floating species. Typha domingensis displaced the other species and reached positive relative cover rate and biomass greater than those at the undisturbed natural environment. T. domingensis proved to be highly efficient for the treatment of wastewater. For that reason, it is the advisable species for the treatment of wastewater of high conductivity and pH enriched with metals, characteristic of many industrial processes.