Constructed wetland treatment system in textile industry and sustainable development

Abstract

This study focuses on the evaluation of the adequacy and sustainability of a constructed wetland (CW), with vertical flow (VF) design to treat a strongly coloured textile wastewater.Secondly an accidental AO7 overloaded discharge (700 mg l(-1)) was studied. A set of three similar VFCW beds (3x1 m2), operating in series, allowed also the efficient treatment of the AO7 heavy loaded wastewaters. The treated effluent quality enables water reuse for irrigation purposes or within the process.

Organic xenobiotics removal in constructed wetlands, with emphasis on the importance of the support matrix

“…CWS have been used to treat a variety of wastewaters including urban runoff, municipal, industrial and agricultural wastewaters [35][36][37]50,[55][56][57][58][60][61][62][63]. In fact, for a long time natural wetlands have been credited with a capacity to depurate the waters that inundated such areas.…”

“…In many of such studies, CWS have been proving to be efficient and cost-effective solutions for the removal of some organic xenobiotics such as pesticides, dyes, explosives, phenolic compounds, petroleum hydrocarbons, pharmaceuticals and hormones [36][37][38]40,[42][43][44][45][46][47][48][49][50][51][52][64][65][66][67][68][69][70][71].…”

“…The implementation of phytotechnologies such as constructed wetland systems (CWS) is becoming a popular option [33][34][35][36][37][38][39]. These systems are increasingly being used to provide a form of secondary, tertiary or quaternary treatment for wastewaters, and have already been used with success to remove several organic xenobiotics of various classes from contaminated waters [36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53].…”

Assessment of successful experiments and limitations of phytotechnologies: contaminant uptake, detoxification and sequestration, and consequences for food safety

“…Isolated plant microsomes, containing enzymes like cytochrome P450 (CYP), are able to hydroxylate chlorobenzoates. Both plants and bacteria which transform or degrade OX (e.g., PCB) are able to further metabolize products of these processes and synergistically remove PCB, nitroesters, pharmaceuticals, and dyes from the environment (Davies et al 2008;Podlipna et al 2008;Huber et al 2009). …”

“…The AsA-GSH cycle somehow interacts with the GST detoxification pathway through increased DHAR activity. The OX effect correlates through the ROS signaling pathway to CAT, SOD, and GPx gene expression at the foliar level (Davies et al 2008). In cell cultures of rhubarb and in whole plants of Rumex, rhubarb, maize, and celery, several sulfonated anthraquinones (AQ-S) are accumulated, metabolized, and even desulfonated; the presence of AQ-S and metabolites in leaves indicates uptake and metabolization (Aubert and Schwitzguébel 2004;Schwitzguébel et al 2008).…”