Performance of high-rate constructed phytoremediation process with attached growth for domestic wastewater treatment: effect of high TDS and Cu

Abstract

Domestic wastewater treatment under specific influent conditions seriously stressed with total dissolved solids (TDS) and copper (Cu) metal was examined by a laboratory-scale model of the phytoremediation process with the attached growth system using Typha sp. As compared with conventional wetland systems, the process showed more stability and improved performance (88 ± 1.1% BOD5, 73 ± 1.0% NH3-N, 48 ± 2.0% PO4-P) at high organic loading rate (314 ± 18 g BOD5/m(3)/d) either in the presence of high TDS (∼2500 mg/L) or Cu metal (∼30 mg/L). Typha sp. could tolerate TDS concentrations up to 2500 mg/L. Cu-contaminated sewage can cause plant morphological deformities if the metal exceeds the saturation limit of 2416 and 21,036 mg/kg Cu in the shoots and roots, respectively. A minor reduction in the TDS (21%) was observed at the highest tolerable limit, whereas 67% reduction of Cu was observed at the process effluent. The process holds a great promise for main advantages of improved biofilm formation, reduced footprint, energy savings and increased efficiency in domestic wastewater treatment even under unfavorable conditions stressed by TDS and Cu.

Keywords: Attached growth; Copper (Cu); Phytoremediation; Sewage; TDS; Typha sp.