Keystone Species and Niche Differentiation Promote Microbial N, P, and COD Removal in Pilot Scale Constructed Wetlands Treating Domestic Sewage

This study was conducted to determine performance of free water surface (FWS) constructed wetlands located in the tropics in the removal of organic matter and to assess the importance of biofilm bacteria in the overall kinetics of organic matter (or chemical oxygen demand, COD) removal. Because constructed wetlands normally contain both biofilm and suspended bacteria, a kinetic model incorporating the activities of these two bacteria groups, dispersion number and hydraulic retention time, was employed. The model parameters essential for the calculation of COD removal in FWS constructed wetlands were determined from the experiments and some from the literature. The model was found satisfactory in predicting COD removal efficiencies in a pilot-scale FWS constructed wetland unit treating a domestic wastewater.

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Enhanced performance of pilot-scale hybrid constructed wetlands with A/O reactor in raw domestic sewage treatment

Journal of Environmental Management ◽

10.1016/j.jenvman.2019.110026 ◽

2020 ◽

Vol 258 ◽

pp. 110026

Author(s):

Chunhui Xiong ◽

Nora Fungyee Tam ◽

Yunv Dai ◽

Xiaomeng Zhang ◽

Rui Li ◽

...

Keyword(s):

Constructed Wetlands ◽

Sewage Treatment ◽

Pilot Scale ◽

Domestic Sewage

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Assessment of clogging in constructed wetlands by saturated hydraulic conductivity measurements

Water Science & Technology ◽

10.2166/wst.2019.045 ◽

2019 ◽

Vol 79 (2) ◽

pp. 314-322 ◽

Cited By ~ 6

Author(s):

F. Licciardello ◽

R. Aiello ◽

V. Alagna ◽

M. Iovino ◽

D. Ventura ◽

...

Keyword(s):

Sensitivity Analysis ◽

Hydraulic Conductivity ◽

Constructed Wetlands ◽

Spatial Scales ◽

Pilot Scale ◽

Laboratory Scale ◽

Test Method ◽

Conductivity Measurements ◽

Multiple Spatial Scales ◽

Ks Values

Abstract This study aims at defining a methodology to evaluate Ks reductions of gravel material constituting constructed wetland (CW) bed matrices. Several schemes and equations for the Lefranc's test were compared by using different gravel sizes and at multiple spatial scales. The falling-head test method was implemented by using two steel permeameters: one impervious (IMP) and one pervious (P) on one side. At laboratory scale, mean K values for a small size gravel (8–15 × 10−2 m) measured by the IMP and the P permeameters were equal to 19,466 m/d and 30,662 m/d, respectively. Mean Ks values for a big size gravel (10–25 × 10−2 m) measured by the IMP and the P permeameters were equal to 12,135 m/d and 20,866 m/d, respectively. Comparison of Ks values obtained by the two permeameters at laboratory scale as well as a sensitivity analysis and a calibration, lead to the modification of the standpipe equation, to evaluate also the temporal variation of the horizontal Ks. In particular, both permeameters allow the evaluation of the Ks decreasing after 4 years-operation and 1–1.5 years' operation of the plants at full scale (filled with the small size gravel) and at pilot scale (filled with the big size gravel), respectively.

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Evaluation of long-term phosphorus uptake by Schoenoplectus californicus and Phragmites australis plants in pilot-scale constructed wetlands

International Journal of Phytoremediation ◽

10.1080/15226514.2021.1960478 ◽

2021 ◽

pp. 1-12

Author(s):

Valentina Carrillo ◽

Cristobal Collins ◽

Jacques Brisson ◽

Gladys Vidal

Keyword(s):

Phragmites Australis ◽

Constructed Wetlands ◽

Phosphorus Uptake ◽

Pilot Scale ◽

Schoenoplectus Californicus

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Removal of six phthalic acid esters (PAEs) from domestic sewage by constructed wetlands

Chemical Engineering Journal ◽

10.1016/j.cej.2015.04.029 ◽

2015 ◽

Vol 275 ◽

pp. 198-205 ◽

Cited By ~ 47

Author(s):

Tang Xiaoyan ◽

Wang Suyu ◽

Yang Yang ◽

Tao Ran ◽

Dai Yunv ◽

...

Keyword(s):

Constructed Wetlands ◽

Phthalic Acid ◽

Domestic Sewage ◽

Phthalic Acid Esters ◽

Acid Esters

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Effect of plants and filter materials on bacteria removal in pilot-scale constructed wetlands

Water Research ◽

10.1016/j.watres.2005.01.005 ◽

2005 ◽

Vol 39 (7) ◽

pp. 1361-1373 ◽

Cited By ~ 113

Author(s):

Gabriela Vacca ◽

Helmut Wand ◽

Marcell Nikolausz ◽

Peter Kuschk ◽

Matthias Kästner

Keyword(s):

Constructed Wetlands ◽

Pilot Scale ◽

Filter Materials ◽

Bacteria Removal

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Application of Biofilm Kinetics to Anaerobic Fixed Bed Reactors

Water Science & Technology ◽

10.2166/wst.1991.0584 ◽

1991 ◽

Vol 23 (7-9) ◽

pp. 1319-1326 ◽

Cited By ~ 4

Author(s):

I. E. Gönenç ◽

D. Orhon ◽

B. Beler Baykal

Keyword(s):

Removal Rate ◽

Fixed Bed ◽

Experimental Studies ◽

Pilot Scale ◽

Cod Removal ◽

Experimental Results ◽

Fixed Bed Reactor ◽

Removal Mechanism ◽

Term Operation ◽

Fixed Bed Reactors

Two basic phenomena, reactor hydraulics and mass transport through biofilm coupled with kinetic expressions for substrate transformations were accounted for in order to describe the soluble COD removal mechanism in anaerobic fixed bed reactors. To provide necessary verification, experimental results from the long term operation of the pilot scale anaerobic reactor treating molasses wastewater were used. Theoretical evaluations verified by these experimental studies showed that a bulk zero-order removal rate expression modified by diffusional resistance leading to bulk half-order and first-order rates together with the particular hydraulic conditions could adequately define the overall soluble COD removal mechanism in an anaerobic fixed bed reactor. The experimental results were also used to determine the kinetic constants for practical application. In view of the complexity of the phenomena involved it is found remarkable that a simple simulation model based on biofilm kinetics is a powerful tool for design and operation of anaerobic fixed bed reactors.

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COD removal efficiency and mechanism of HMBR in high volumetric loading for ship domestic sewage treatment

Water Science & Technology ◽

10.2166/wst.2016.271 ◽

2016 ◽

Vol 74 (7) ◽

pp. 1509-1517 ◽

Cited By ~ 4

Author(s):

Linan Zhu ◽

Hailing He ◽

Chunli Wang

Keyword(s):

Removal Efficiency ◽

Removal Rate ◽

Sewage Treatment ◽

Oxygen Demand ◽

Domestic Sewage ◽

Cod Removal ◽

Aeration Tank ◽

Remarkable Effect ◽

Cod Removal Efficiency ◽

Volumetric Loading

The hybrid membrane bioreactor (HMBR) has been applied in ship domestic sewage treatment under high volumetric loading for ship space saving. The mechanism and influence factors on the efficiency, including hydraulic retention time (HRT), dissolved oxygen (DO) of chemical oxygen demand (COD) removal were investigated. The HMBR's average COD removal rate was up to 95.13% on volumetric loading of 2.4 kgCOD/(m3•d) and the COD concentration in the effluent was 48.5 mg/L, far below the International Maritime Organization (IMO) discharge standard of 125 mg/L. DO had a more remarkable effect on the COD removal efficiency than HRT. In addition, HMBR revealed an excellent capability of resisting organics loading impact. Within the range of volumetric loading of 0.72 to 4.8 kg COD/(m3•d), the effluent COD concentration satisfied the discharge requirement of IMO. It was found that the organics degradation in the aeration tank followed the first-order reaction, with obtained kinetic parameters of vmax (2.79 d−1) and Ks (395 mg/L). The original finding of this study had shown the effectiveness of HMBR in organic contaminant degradation at high substrate concentration, which can be used as guidance in the full scale of the design, operation and maintenance of ship domestic sewage treatment devices.

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