Characterization of unconventional sand-based substrates for adsorption of micropollutants in nature-based systems

in Journal of Environmental Management (2022)

The focus of this study is the characterization of unconventional sand-based substrates used in our previous project EmiSûre, (Interreg Greater Region (German federal states Rhineland-Palatinate and ... [more ▼]

The focus of this study is the characterization of unconventional sand-based substrates used in our previous project EmiSûre, (Interreg Greater Region (German federal states Rhineland-Palatinate and Saarland, the Grand Duchy of Luxembourg, regions Wallonia and Lorraine from Belgium and France, respectively), 2017–2021). The project aimed to develop and test alternative, nature-based technologies for the elimination of micropollutants (MPs) from municipal wastewater. For the characterization, two approaches were chosen. In the first approach, adsorption kinetics with a single compound allowed a perception of the adsorption capacity of the studied substrates compared to conventional substrates (granular activated carbons). This knowledge was completed by the second approach: an implementation of the studied substrates in packed-bed columns, which treated a mixture of 27 MPs in tap water for 10 months. Additionally, all three substrates (bentonite sand, sand with 15% activated biochar and sand with 15% zeolite) were characterized for physical and chemical properties, and the microbial potential of the activated and non-activated biochar was examined. From the studies, it is clear that the sand with an admixture of activated biochar is the most efficient sorbent in terms of single compound adsorption in batch (dye) and adsorption of 27 MPs on packed-bed columns. In contrast to the two other substrates, it shows long-term stable removal efficiencies. In the packed-bed columns, 18 out of 27 compounds were removed on average with high efficiency (80–99%), which is impressive, if we consider the variety of the compounds examined (pharmaceuticals, herbicides, pesticides, etc.) and their removal in conventional treatments. Addi- tionally, adsorption models were created for the experimental data of all compounds adsorbed on the substrate with an admixture of activated biochar resulting in the best fit with the combined Langmuir-Freundlich model. These satisfying results suggest the application of the sand-based substrate with an admixture of activated biochar for further research and possibly upscale installations with the aim to offer and prove a reasonable and efficient alternative for MPs elimination from municipal wastewater. [less ▲]

Bioremediation of 27 Micropollutants by Symbiotic Microorganisms of Wetland Macrophytes

in Sustainability (2022), 14(7), 3944

Background: Micropollutants in bodies of water represent many challenges. We addressedthese challenges by the application of constructed wetlands, which represent advanced treatmenttechnology for the ... [more ▼]

Background: Micropollutants in bodies of water represent many challenges. We addressedthese challenges by the application of constructed wetlands, which represent advanced treatmenttechnology for the removal of micropollutants from water. However, which mechanisms specificallycontribute to the removal efficiency often remains unclear. Methods: Here, we focus on the removalof 27 micropollutants by bioremediation. For this, macrophytesPhragmites australis,Iris pseudacorusandLythrum salicariawere taken from established wetlands, and a special experimental set-up wasdesigned. In order to better understand the impact of the rhizosphere microbiome, we determinedthe microbial composition using 16S rRNA gene sequencing and investigated the role of identifiedgenera in the micropollutant removal of micropollutants. Moreover, we studied the colonizationof macrophyte roots by arbuscular mycorrhizal fungi, which are known for their symbiotic rela-tionship with plants. This symbiosis could result in increased removal of present micropollutants.Results: We foundIris pseudacorusto be the most successful bioremediative system, as it removed22 compounds, including persistent ones, with more than 80% efficiency. The most abundant generathat contributed to the removal of micropollutants werePseudomonas, Flavobacterium, Variovorax,Methylotenera, Reyranella, AmaricoccusandHydrogenophaga.Iris pseudacorusexhibited the highest colo-nization rate (56%). Conclusions: Our experiments demonstrate the positive impact of rhizospheremicroorganisms on the removal of micropollutants. [less ▲]

QUANTIFICATION OF MICROPOLLUTANT REMOVAL MECHANISMS IN VERTICAL-FLOW CONSTRUCTED WETLANDS: OUTCOME OF THE ‘EMISÛRE’ PROJECT

in Book of Abstracts - "9th International Symposium on Wetland Pollutant Dynamics and Control - WETPOL 2021" (2021, September 15)

Quantification of removal mechanisms in vertical flow constructed wetlands as nature based solutions for treatment of wastewater effluent

Poster (2021, March 18)

Removal of micropollutants in medium-sized WWTP by vertical flow constructed wetlands (VFCWs): performance under laboratory and real conditions

in Removal of micropollutants in medium-sized WWTP by vertical flow constructed wetlands (VFCWs): performance under laboratory and real conditions (2020, February 14)

Micropollutants generated in urban agglomerates are commonly found in aquatic environments where they may present a potential danger. Constructed wetlands (CWs) are an attractive alternative for the ... [more ▼]

Micropollutants generated in urban agglomerates are commonly found in aquatic environments where they may present a potential danger. Constructed wetlands (CWs) are an attractive alternative for the removal of those compounds from the effluent of medium-sized wastewater treatment plants (WWTPs). To this end, the INTERREG Greater Region-funded project EmiSûre aims to find solutions to mitigate the emission of micropollutants from wastewater facilities. As a part of the project, this study starts with the trial of vertical flow (VF) CWs under lab-scale conditions aiming to select the best substrate. Following steps are designed to optimize the performance of VFCWs in terms of removal of micropollutans under real conditions (i.e. matrix, seasonal changes, temperature) and to derive first approaches for dimensioning. From all the examined substrates, activated biocoal showed the best results in removing macro- and micropollutants and is expected to be the most suitable substrate in long term perspectives. [less ▲]

ROLE OF TARGETED BIOCHAR-ACTIVATION IN THE REMOVAL OF MACRO- AND MICROPOLLUTANTS FROM SECONDARY EFFLUENT WASTEWATER

in Book of Abstracts 8th International Symposium On Wetland Pollutant Dynamics and Control (2019, January 30)

Emisure - nature oriented systems for removal of micropollutants from wastewater

Scientific Conference (2018, March 13)