Strategies and techniques to enhance constructed wetland performance for sustainable wastewater treatment

Abstract

Constructed wetlands (CWs) have been used as an alternative to conventional technologies for wastewater treatment for more than five decades. Recently, the use of various modified CWs to improve treatment performance has also been reported in the literature. However, the available knowledge on various CW technologies considering the intensified and reliable removal of pollutants is still limited. Hence, this paper aims to provide an overview of the current development of CW strategies and techniques for enhanced wastewater treatment. Basic information on configurations and characteristics of different innovations was summarized. Then, overall treatment performance of those systems and their shortcomings were further discussed. Lastly, future perspectives were also identified for specialists to design more effective and sustainable CWs. This information is used to inspire some novel intensifying methodologies, and benefit the successful applications of potential CW technologies.

Optimization of organics and nitrogen removal in intermittently aerated vertical flow constructed wetlands: Effects of aeration time and aeration rate

“…The experiment was carried out in Baihua Park in Jinan, China as described in detail by Wu et al (2015b). Eleven parallel microcosm VF CWs were constructed for treating simulated domestic wastewater in this study.…”

“…3 that NO 3 --N increased to be the dominant form as the aeration time increased from 6 h d -1 to 10 h d -1 due to excessive aeration. Additionally, limited available organic matters might restrain the denitrification process (Saeed and Sun, 2012;Wu et al, 2015b).…”

“…Constructed wetland (CW), as the one of the widely used ecological technologies, has been attracted more attention as the alternative solutions for wastewater treatment in these years, owing to the advantages of good efficiency, low cost and low maintenance (Vymazal, 2011;Feng et al, 2012;Chyan et al, 2013;Wu et al, 2015b). According to water level, CWs can be classified as free water surface (FWS) CWs and subsurface flow (SSF) CWs which could be further divided into vertical flow (VF) and hori-zontal flow (HF) CWs.…”

“…According to water level, CWs can be classified as free water surface (FWS) CWs and subsurface flow (SSF) CWs which could be further divided into vertical flow (VF) and hori-zontal flow (HF) CWs. Among those kinds of CWs, VF CWs have been widely used for decentralized sewage treatment because of a higher oxygen transfer rate and adaption to cold climate (García et al, 2010;Saeed and Sun, 2012;Wu et al, 2015b).…”

Secondary effluent purification by a large-scale multi-stage surface-flow constructed wetland: A case study in northern China

“…Furthermore, it is generally accepted that CWs can treat wastewater within an optimal load capacity range, and out of range or changes in hydraulic loading will affect the oxygen environment and the removal processes of organic pollutants in CWs (Rai et al, 2013;Saeed and Sun, 2012;Wu et al, 2015a). Therefore, some alternative preventive measures and enhancing strategies such as insulation measurements, decreasing hydraulic loading, psychrotrophic bacteria addition, and seasonal plant collocation should be considered to improve wastewater treatment efficiency of CWs at low temperature in the future full-scale application (Wu et al, 2015b;Zhang et al, 2017).…”