Impact of Ornamental Vegetation Type and Different Substrate Layers on Pollutant Removal in Constructed Wetland Mesocosms Treating Rural Community Wastewater

Improving water quality is a relevant environmental aspect, and using constructed wetlands (CWs) is a sustainable option for this; both porous material filled cells and plants that collectively remove contaminants must be readily available and inexpensive. This study evaluated CWs and their functionality by comparing two ornamental plants (Spathiphyllum wallisii and Hedychium coronarium) planted in experimental mesocosm units filled with layers of porous river rock, tepezil, and soil, or in mesocosms with layers of porous river rock, and tepezil, without the presence of soil. The findings during the experiments (180 days), showed that the removal of pollutants (chemical oxygen demand (COD), total solids suspended (TSS), nitrogen as ammonium (N-NH4), as nitrate (N-NO3), and phosphate (P-PO4) was 20–50% higher in mesocosms with vegetation that in the absence of this, and those mesocosms with the soil layer between 33–45% favored removal of P-PO4. Differences regarding of vegetation removal were only observed for N-NH4, being 25–45% higher in CWs with H. coronarium, compared with S. wallisii. Both species are suitable for using in CWs, for its functionality as phytoremediation, and aesthetic advantages could generate interest for wastewater treatment in rural communities, parks, schools or in domiciliary levels like floral flower boxes in the backyard. The study also revealed that a soil layer in CWs is necessary to increase the removal of P-PO4, an ion hardly eliminated in water treatment.

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Wastewater Treatment by Constructed Wetland Eco-Technology: Influence of Mineral and Plastic Materials as Filter Media and Tropical Ornamental Plants

Water ◽

10.3390/w11112344 ◽

2019 ◽

Vol 11 (11) ◽

pp. 2344 ◽

Cited By ~ 4

Author(s):

Sergio Zamora ◽

J. Luis Marín-Muñíz ◽

Carlos Nakase-Rodríguez ◽

Gregorio Fernández-Lambert ◽

Luis Sandoval

Keyword(s):

Wastewater Treatment ◽

Ornamental Plants ◽

Oxygen Demand ◽

Filter Material ◽

Pollutant Removal ◽

Cyperus Papyrus ◽

Sustainable Technologies ◽

Hedychium Coronarium ◽

Plastic Materials ◽

Ammonium N

Constructed wetlands (CWs) are sustainable technologies where the channels are filled with porous material and plants, which collectively remove pollutants, depending on the type of substrate and vegetation. This study evaluated CWs and their functionality by comparing three ornamental plants (Canna indica, Cyperus papyrus, and Hedychium coronarium) as a phytoremediation process of wastewater, in CWs filled with layers of porous stone–tepezil–plastic residues–soil (S-A), or in microcosms with layers of porous stone–tepezil–soil without the presence of plastic (S-B). The findings during 180 days showed that the removals of pollutants (chemical oxygen demand (COD), total solids suspended (TSS), nitrogen as ammonium (N-NH4), as nitrate (N-NO3), and phosphate (P-PO4) were 20%–60% higher in microcosms with plants than in the absence of plants. Statistical differences were not observed when comparing removal effects among S-A and S-B, indicating that plastic residues as filter material in CWs did not affect the pollutant removal, growth, flowering, and shoots of plants. The use of plastic residues as filter may represent a less costly alternative in CW establishments. Dependence on N-NH4 and TSS removal was observed according to plant species. The three species used are suitable for using in CWs as wastewater treatment. In addition, the ornamental plants could generate interest for a commercial option.

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Effects of the Use of Ornamental Plants and Different Substrates in the Removal of Wastewater Pollutants through Microcosms of Constructed Wetlands

Sustainability ◽

10.3390/su10051594 ◽

2018 ◽

Vol 10 (5) ◽

pp. 1594 ◽

Cited By ~ 16

Author(s):

Luis Sandoval-Herazo ◽

Alejandro Alvarado-Lassman ◽

José Marín-Muñiz ◽

Juan Méndez-Contreras ◽

Sergio Aurelio Zamora-Castro

Keyword(s):

Rural Communities ◽

Constructed Wetlands ◽

Rural Areas ◽

Ornamental Plants ◽

Oxygen Demand ◽

Added Value ◽

Fecal Coliforms ◽

Zantedeschia Aethiopica ◽

Wastewater Pollutants ◽

Pet Substrate

The high costs involved in treating wastewater are problems that developing countries confront, mainly in rural areas. Therefore, Constructed Wetlands (CWs), which are composed of substrate, vegetation, and microorganisms, are an economically and ecologically viable option for wastewater treatment in these places. There is a wide variety of possibilities for substrates and ornamental plants that have not yet been evaluated to be implemented in future CW designs. The goal of this study was to evaluate the process of adaptation and removal of wastewater pollutants in CW microcosms using different terrestrial ornamental plants (Lavandula sp., Spathiphyllum wallisii, and Zantedeschia aethiopica). Those plants were sown in two types of substrate: red volcanic gravel (RVG) and polyethylene terephthalate (PET). CWs with vegetation reduced 5-day biochemical oxygen demand (BOD5) by 68% with RVG substrate and 63% with PET substrate, nitrates 50% in RVG substrate and 35% in PET substrate, phosphates 38% in RVG substrate and 35% in PET substrate, and fecal coliforms 64% in RVG and 59% in PET substrate). In control microcosms without vegetation, reductions were significantly lower than those in the presence of plants, with reduction of BOD5 by 61% in RVG substrate and 55% in PET substrate, nitrates 26% in RVG substrate and 22% in PET substrate, phosphates 27% in RVG substrate and 25% in PET substrate. Concerning fecal coliforms 62% were removed in RVG substrate and 59% in PET substrate. Regarding the production of flowers, Lavandula sp. did not manage to adapt and died 45 days after sowing and did not produce flowers. Spathiphyllum wallisii produced 12 flowers in RVG and nine flowers in PET, while Zantedeschia aethiopica produced 10 in RVG and 7 in PET. These results showed that the use of substrates made of RVG and PET is a viable alternative to be implemented in CWs. In addition, the reuse of PET is an option that decreases pollution by garbage. The plants Spathiphyllum wallisii and Zantedeschia aethiopica remarkably contribute in the removal of pollutants in wastewater. Additionally, the use of ornamental plants, with commercial interest such as those evaluated, enables an added value to the CW to be given, which can be used for flower production purposes on a larger scale and favor its acceptance within rural communities.

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Effect of Ornamental Plants, Seasonality, and Filter Media Material in Fill-and-Drain Constructed Wetlands Treating Rural Community Wastewater

Sustainability ◽

10.3390/su11082350 ◽

2019 ◽

Vol 11 (8) ◽

pp. 2350 ◽

Cited By ~ 2

Author(s):

Sergio A. Zamora-Castro ◽

José Luis Marín-Muñiz ◽

Luis Sandoval ◽

Monserrat Vidal-Álvarez ◽

Juan Manuel Carrión-Delgado

Keyword(s):

Chemical Oxygen Demand ◽

Removal Efficiency ◽

Constructed Wetlands ◽

Ornamental Plants ◽

Oxygen Demand ◽

Biomass Productivity ◽

Pollutant Removal ◽

Filter Media ◽

Control Units ◽

Phosphorous Compounds

The effects of Canna indica (P1), Pontederia sagittata (P2), and Spathiphyllum wallisii (P3) growing in different filter media materials (12 using porous river rock and 12 using tepezyl) on the seasonal removal of pollutants of wastewater using fill-and-drain constructed wetlands (FD-CWs) were investigated during 12 months. Three units of every media were planted with one plant of P1, P2, and P3, and three were kept unplanted. C. indica was the plant with higher growth than the other species, in both filter media. The species with more flower production were: C. indica > P. sagittate > S. wallisii. Reflecting similarly in the biomass of the plants, C. indica and P. sagittata showed more quantity of aerial and below ground biomass productivity than S. wallisii. With respect to the removal efficiency, both porous media were efficient in terms of pollutant removal performance (p > 0.05). However, removal efficiency showed a dependence on ornamental plants. The higher removal of chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total kjeldahl nitrogen (TKN), nitrates (NO3−-N), ammonium (NH4+-N), and phosphates (PO4−3-P) oscillated between 81% to 83%, 80% to 84%, 61% to 69%, 61% to 68%, 65% to 71%, 62% to 68%, and 66% to 69%, respectively, in P1 and P2, removals 15% to 30% higher than P3. The removal in planted microcosms was significantly higher than the unplanted control units (p = 0.023). Nitrogen and phosphorous compounds were highly removed (60%–80%) because in typical CWs, such pollutant removals are usually smaller, indicating the importance of FD-CWs on wastewater treatments using porous river rock and tepezyl as porous filter media. (BOD5), chemical oxygen demand (COD), (NO3−-N), (NH4+-N), (TKN), and (PO4−3-P).

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Performance of hybrid subsurface constructed wetland system for piggery wastewater treatment

Water Science & Technology ◽

10.2166/wst.2015.457 ◽

2015 ◽

Vol 73 (1) ◽

pp. 13-20 ◽

Cited By ~ 11

Author(s):

X. Zhang ◽

T. Inoue ◽

K. Kato ◽

J. Harada ◽

H. Izumoto ◽

...

Keyword(s):

Wastewater Treatment ◽

Constructed Wetland ◽

Removal Rate ◽

Oxygen Demand ◽

Total Coliform ◽

Organic Content ◽

Pollutant Removal ◽

Total Carbon ◽

Piggery Wastewater ◽

Ammonium N

The objective of this study was to evaluate performance of a hybrid constructed wetland (CW) built for high organic content piggery wastewater treatment in a cold region. The system consists of four vertical and one horizontal flow subsurface CWs. The wetland was built in 2009 and water quality was monitored from the outset. Average purification efficiency of this system was 95 ± 5, 91 ± 7, 89 ± 8, 70 ± 10, 84 ± 15, 90 ± 6, 99 ± 2, and 93 ± 16% for biochemical oxygen demand (BOD5), chemical oxygen demand (COD), total carbon (TC), total nitrogen (TN), ammonium-N (NH4-N), total phosphorus (TP), total coliform (T. Coliform), and suspended solids (SS), respectively during August 2010–December 2013. Pollutant removal rate was 15 ± 18 g m−2 d−1, 49 ± 52 g m−2 d−1, 6 ± 4 g m−2 d−1, 7 ± 5 g m−2 d−1, and 1 ± 1 g m−2 d−1 for BOD5, COD, TN, NH4-N, and TP, respectively. The removal efficiency of BOD5, COD, NH4-N, and SS improved yearly since the start of operation. With respect to removal of TN and TP, efficiency improved in the first three years but slightly declined in the fourth year. The system performed well during both warm and cold periods, but was more efficient in the warm period. The nitrate increase may be attributed to a low C/N ratio, due to limited availability of carbon required for denitrification.

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Effect of Aeration Modes and COD/N Ratios on Organic Matter and Nitrogen Removal in Horizontal Subsurface Flow Constructed Wetland Mesocosms

Water ◽

10.3390/w10111530 ◽

2018 ◽

Vol 10 (11) ◽

pp. 1530 ◽

Cited By ~ 2

Author(s):

Xin Chen ◽

Hui Zhu ◽

Yingying Xu ◽

Brian Shutes ◽

Baixing Yan ◽

...

Keyword(s):

Nitrogen Removal ◽

Subsurface Flow ◽

Oxygen Demand ◽

Ammonia Nitrogen ◽

Pollutant Removal ◽

Artificial Aeration ◽

Influent Water ◽

Horizontal Subsurface Flow ◽

Aerobic And Anaerobic ◽

Wetland Mesocosms

A series of mesocosm-scale horizontal subsurface flow constructed wetlands (HSSF-CWs) were established. In Experiment 1, four artificial aeration (AA) modes, including pre-aeration at 24 h before the input of influent water (PA), aeration at 6 h (6AA) and 12 h (12AA) after the input of influent water and non-aeration (NA), were tested to obtain an optimal aeration mode for chemical oxygen demand (CODCr) and nitrogen removal. The results showed that aeration after the input of influent water could improve the removal efficiencies of CODCr and ammonia-nitrogen (NH4⁺-N), but lead to an accumulation of nitrate-nitrogen (NO3−-N). The above observation demonstrated that a single aeration cannot create an ideal alternation of aerobic and anaerobic conditions for simultaneous nitrification and denitrification. Therefore, HSSF-CWs with intermittent aeration (IA), after the input of influent water and NA were established to evaluate the combined effects of IA and influent COD/N ratios on pollutant removal in Experiment 2. The HSSF-CW with IA exhibited a better performance in CODCr and nitrogen removal compared to HSSF-CW with NA. The highest removal percentages of CODCr (90.1%), NH4+-N (99.8%) and total nitrogen (TN, 99.5%) were achieved at a COD/N ratio of 9.3 in HSSF-CW with IA.

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Removal of organic pollutants from produced water by batch adsorption treatment

Clean Technologies and Environmental Policy ◽

10.1007/s10098-021-02159-z ◽

2021 ◽

Author(s):

Eman Hashim Khader ◽

Thamer Jassim Mohammed ◽

Nourollah Mirghaffari ◽

Ali Dawood Salman ◽

Tatjána Juzsakova ◽

...

Keyword(s):

Activated Carbon ◽

Produced Water ◽

Oxygen Demand ◽

Powdered Activated Carbon ◽

Pollutant Removal ◽

Operating Conditions ◽

Isotherm Models ◽

Batch Adsorption ◽

Order Kinetic ◽

Zeolite X

AbstractThis paper studied the adsorption of chemical oxygen demand (COD), oil and turbidity of the produced water (PW) which accompanies the production and reconnaissance of oil after treating utilizing powdered activated carbon (PAC), clinoptilolite natural zeolite (CNZ) and synthetic zeolite type X (XSZ). Moreover, the paper deals with the comparison of pollutant removal over different adsorbents. Adsorption was executed in a batch adsorption system. The effects of adsorbent dosage, time, pH, oil concentration and temperature were studied in order to find the best operating conditions. The adsorption isotherm models of Langmuir, Freundlich and Temkin were investigated. Using pseudo-first-order and pseudo-second-order kinetic models, the kinetics of oil sorption and the shift in COD content on PAC and CNZ were investigated. At a PAC adsorbent dose of 0.25 g/100 mL, maximum oil removal efficiencies (99.57, 95.87 and 99.84 percent), COD and total petroleum hydrocarbon (TPH) were identified. Moreover, when zeolite X was used at a concentration of 0.25 g/100 mL, the highest turbidity removal efficiency (99.97%) was achieved. It is not dissimilar to what you would get with PAC (99.65 percent). In comparison with zeolites, the findings showed that adsorption over PAC is the most powerful method for removing organic contaminants from PW. In addition, recycling of the consumed adsorbents was carried out in this study to see whether the adsorbents could be reused. Chemical and thermal treatment will effectively regenerate and reuse powdered activated carbon and zeolites that have been eaten. Graphic abstract

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Efficiency and Technological Reliability of Contaminant Removal in Household WWTPs with Activated Sludge

Applied Sciences ◽

10.3390/app11041889 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1889 ◽

Cited By ~ 1

Author(s):

Agnieszka Micek ◽

Krzysztof Jóźwiakowski ◽

Michał Marzec ◽

Agnieszka Listosz ◽

Tadeusz Grabowski

Keyword(s):

Activated Sludge ◽

Wastewater Treatment Plants ◽

Oxygen Demand ◽

Domestic Wastewater ◽

Pollutant Removal ◽

Treated Wastewater ◽

Contaminant Removal ◽

Nitrogen And Phosphorus ◽

Wastewater Samples ◽

Polish Law

The results of research on the efficiency and technological reliability of domestic wastewater purification in two household wastewater treatment plants (WWTPs) with activated sludge are presented in this paper. The studied facilities were located in the territory of the Roztocze National Park (Poland). The mean wastewater flow rate in the WWTPs was 1.0 and 1.6 m3/day. In 2017–2019, 20 series of analyses were done, and 40 wastewater samples were taken. On the basis of the received results, the efficiency of basic pollutant removal was determined. The technological reliability of the tested facilities was specified using the Weibull method. The average removal efficiencies for the biochemical oxygen demand in 5 days (BOD5) and chemical oxygen demand (COD) were 66–83% and 62–65%, respectively. Much lower effects were obtained for total suspended solids (TSS) and amounted to 17–48%, while the efficiency of total phosphorus (TP) and total nitrogen (TN) removal did not exceed 34%. The analyzed systems were characterized by the reliability of TSS, BOD5, and COD removal at the level of 76–96%. However, the reliability of TN and TP elimination was less than 5%. Thus, in the case of biogenic compounds, the analyzed systems did not guarantee that the quality of treated wastewater would meet the requirements of the Polish law during any period of operation. This disqualifies the discussed technological solution in terms of its wide application in protected areas and near lakes, where the requirements for nitrogen and phosphorus removal are high.

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Treatment performances of French constructed wetlands: results from a database collected over the last 30 years

Water Science & Technology ◽

10.2166/wst.2015.089 ◽

2015 ◽

Vol 71 (9) ◽

pp. 1333-1339 ◽

Cited By ~ 30

Author(s):

A. Morvannou ◽

N. Forquet ◽

S. Michel ◽

S. Troesch ◽

P. Molle

Keyword(s):

Constructed Wetlands ◽

Oxygen Demand ◽

Pollutant Removal ◽

Vertical Flow ◽

Removal Rates ◽

Waste Stabilization Ponds ◽

Small Communities ◽

Technical Department ◽

In Series ◽

High Chemical Oxygen Demand

Approximately 3,500 constructed wetlands (CWs) provide raw wastewater treatment in France for small communities (<5,000 people equivalent). Built during the past 30 years, most consist of two vertical flow constructed wetlands (VFCWs) in series (stages). Many configurations exist, with systems associated with horizontal flow filters or waste stabilization ponds, vertical flow with recirculation, partially saturated systems, etc. A database analyzed 10 years earlier on the classical French system summarized the global performances data. This paper provides a similar analysis of performance data from 415 full-scale two-stage VFCWs from an improved database expanded by monitoring data available from Irstea and the French technical department. Trends presented in the first study are confirmed, exhibiting high chemical oxygen demand (COD), total suspended solids (TSS) and total Kjeldahl nitrogen (TKN) removal rates (87%, 93% and 84%, respectively). Typical concentrations at the second-stage outlet are 74 mgCOD L−1, 17 mgTSS L−1 and 11 mgTKN L−1. Pollutant removal performances are summarized in relation to the loads applied at the first treatment stage. While COD and TSS removal rates remain stable over the range of applied loads, the spreading of TKN removal rates increases as applied loads increase.

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Biogeochemical indicators to evaluate pollutant removal efficiency in constructed wetlands

Water Science & Technology ◽

10.2166/wst.1997.0152 ◽

1997 ◽

Vol 35 (5) ◽

pp. 1-10 ◽

Cited By ~ 53

Author(s):

K. R. Reddy ◽

E. M. D'Angelo

Keyword(s):

Microbial Biomass ◽

Removal Efficiency ◽

Nitrate Removal ◽

Oxygen Demand ◽

Acid Soils ◽

Pollutant Removal ◽

Alkaline Soils ◽

Organic C ◽

Wetland Treatment ◽

Biogeochemical Indicators

Wetlands support several aerobic and anaerobic biogeochemical processes that regulate removal/retention of pollutants, which has encouraged the intentional use of wetlands for pollutant abatement. The purpose of this paper is to present a brief review of key processes regulating pollutant removal and identify potential indicators that can be measured to evaluate treatment efficiency. Carbon and toxic organic compound removal efficiency can be determined by measuring soil or water oxygen demand, microbial biomass, soil Eh and pH. Similarly, nitrate removal can be predicted by dissolved organic C and microbial biomass. Phosphorus retention can be described by the availability of reactive Fe and Al in acid soils and Ca and Mg in alkaline soils. Relationships between soil processes and indicators are useful tools to transfer mechanistic information between diverse types of wetland treatment systems.

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Using one filter stage of unsaturated/saturated vertical flow filters for nitrogen removal and footprint reduction of constructed wetlands

Water Science & Technology ◽

10.2166/wst.2017.115 ◽

2017 ◽

Vol 76 (1) ◽

pp. 124-133 ◽

Cited By ~ 4

Author(s):

Ania Morvannou ◽

Stéphane Troesch ◽

Dirk Esser ◽

Nicolas Forquet ◽

Alain Petitjean ◽

...

Keyword(s):

Constructed Wetlands ◽

Oxygen Demand ◽

Pollutant Removal ◽

Operating Conditions ◽

Vertical Flow ◽

Saturated Layer ◽

Recirculation Rate ◽

Total Filtration ◽

Filtration Area ◽

Stage System

French vertical flow constructed wetlands (VFCW) treating raw wastewater have been developed successfully over the last 30 years. Nevertheless, the two-stage VFCWs require a total filtration area of 2–2.5 m2/P.E. Therefore, implementing a one-stage system in which treatment performances reach standard requirements is of interest. Biho-Filter® is one of the solutions developed in France by Epur Nature. Biho-Filter® is a vertical flow system with an unsaturated layer at the top and a saturated layer at the bottom. The aim of this study was to assess this new configuration and to optimize its design and operating conditions. The hydraulic functioning and pollutant removal efficiency of three different Biho-Filter® plants commissioned between 2011 and 2012 were studied. Outlet concentrations of the most efficient Biho-Filter® configuration are 70 mg/L, 15 mg/L, 15 mg/L and 25 mg/L for chemical oxygen demand (COD), 5-day biological oxygen demand (BOD5), total suspended solids (TSS) and total Kjeldahl nitrogen (TKN), respectively. Up to 60% of total nitrogen is removed. Nitrification efficiency is mainly influenced by the height of the unsaturated zone and the recirculation rate. The optimum recirculation rate was found to be 100%. Denitrification in the saturated zone works at best with an influent COD/NO3-N ratio at the inflet of this zone larger than 2 and a hydraulic retention time longer than 0.75 days.

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