• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.129-129
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• 2021

Constructed wetlands (CW) are artificially developed wetlands that are used to control water pollution. In central India, the field application of CW started on the late 1990s but are mostly focused on wastewater treatment. In this paper, different existing and experimental studies on constructed wetlands were reviewed to be able to determine the current status of wetlands in India to identify the type of CW that is more suitable in managing a specific target pollutant and type of wastewater. Wetlands were categorized into three types: vertical flow, horizontal flow, and hybrid while the wastewater were classified as domestic and industrial. Based on the review, 80% of constructed wetlands are used for treating domestic wastewater while 20% are treating industrial wastewater. Inflow analysis showed that industrial wastewater in hybrid constructed wetland produced the highest average concentration for parameters like COD (2851 mg/L) and BOD (5715 mg/L) while the lowest concentration was TN (13.97 mg/L) found in municipal wastewater. In terms of removing nonpoint source pollutants, it was revealed that vertical flow constructed wetlands (VFCW) are more effective at removing TSS and BOD as compared to horizontal flow constructed wetlands (HFCW) and hybrid constructed wetlands (HCW). HCW were found to be capable of efficiently removing COD and TN. Meanwhile, HFCW showed the highest TP removal among all the types of wetlands. In addition, VFCW were more effective for domestic wastewater while HCW are more effective for treating industrial wastewater. Lastly, there is currently a need to conduct further research on constructed wetlands for industrial wastewater as well as stormwater treatment to be able to gather more data and improve wetland design, performance, and maintenance.

• Environmental Engineering Research
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• v.24 no.2
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• pp.181-190
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• 2019

Constructed wetlands are improvised man-made systems, designed for adopting the principle of natural wetlands for purifying wastewater - the elixir of life. They are used widely as a cost-effective and energy-efficient solution for treating greywater generated from different tertiary treatment sources. It provides an elaborate platform for research activities in an attempt to recycle earth's natural resources. Among the several organic impurities removal mechanisms existing in constructed wetland systems, the earth's active microbial population plays a vital role. This review deals with the recent advancements in constructed wetland systems from a microbiological perspective to (effect/ devise/ formulate) chemical and physical treatment for water impurities. It focuses on microbial diversity studies in constructed wetlands, influence of wetland media on microbial diversity and wetland performance, role of specific microbes in water reuse, removal of trace elements, some heavy metals and antibiotics in constructed wetlands. The impurities removal processes in constructed wetlands is achieved by combined interactive systems such as selected plant species, nature of substrate used for microbial diversity and several biogeochemical effected reaction cycles in wetland systems. Therefore, the correlation studies that have been conducted by earlier researchers in microbial diversity in wetlands are addressed herewith.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.497-500
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• 2001

Constructed wetlands are among the recently proven efficient technologies for wastewater treatment. Compared to conventional treatment systems, constructed wetlands are low cost, are easily operated and maintained. Constructed wetlands are particularly sensitive to Nonp oint source pollution(NPSP) because they function as pollutant sinks. The objectives of this study were to review the necessary contents of survey and design factors for constructing constructed wetlands and develop a modified DSS-WQMRA model for design of constructed wetlands. From the results of the case studies, in order to attain BOD target water quality, 0.27%(SF), 0.66%(FWS) wetland area of the total basin is needed.

• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.5
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• pp.96-105
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• 2002

As an useful water purification system for non-point source pollution in rural watersheds, interests in constructed wetlands are growing at home and abroad. It is well known that constructed wetlands are easily installed, no special managemental needs, and more flexible at fluctuating influent loads. They have a capacity for purification against nutrient materials such as phosphorus and nitrogen causing eutrophication of lentic water bodies. The Constructed Wetland Design Model (CWDM), developed through this study is consisted mainly of Database System, Runoff-discharge Prediction Submodel, Water Quality Prediction Submodel, and Area Assessment Submodel. The Database System includes data of watershed, discharge, water quality, pollution source, and design factors for the constructed wetland. It supplies data when predicting water quality and calculating the required areas of constructed wetlands. For the assessment of design flow, the GWLF (Generalized Watershed Loading Function) is used, and for water quality prediction in streams estimating influent pollutant load, Water Quality Prediction Submodel, that is a submodel of DSS-WQMRA model developed by previous works is amended. The calculation of the required areas of constructed wetlands is achieved using effluent target concentrations and area calculation equations that developed from the monitoring results in the United States. The CWDM is applied to Bokha watershed to appraise its application by assessing design flow and predicting water quality. Its application is performed through two calculations: one is to achieve each target effluent concentrations of BOD, SS, T-N and T-P, the other is to achieve overall target effluent concentrations. To prove the validity of the model, a comparison of unit removal rates between the calculated one from this study and the monitoring result from existing wetlands in Korea, Japan and United States was made. As a result, the CWDM could be very useful design tool for the constructed wetland in rural watersheds and for the non-point source pollution management.

• Environmental Engineering Research
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• v.10 no.6
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• pp.316-327
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• 2005

Constructed wetlands provide several benefits that are not solely limited to storm water management and are becoming common in storm water management. In this research, four recently constructed wetlands underwent in situ and laboratory water sampling to determine their efficiency in removing storm water pollutants over a 5-month period. From the sampling results, it was determined that each of the wetlands was able to reduce the concentration of pollutants in the stormwater. To aid in the assessment of the wetlands against each other, a model was developed to determine the extent of removal of stormwater pollutants over the length of the wetland. The results from this model complimented the data collected from the field. Improvements, such as increased amounts of vegetation were recommended for the wetlands with the aim of increasing the effectiveness. Further investigations into the wetlands will allow for better understanding of the wetland's performance.

• Membrane and Water Treatment
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• v.11 no.2
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• pp.87-95
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• 2020

The worldwide shortage of water resources is a major environmental issue. Using pure water for drinking and domestic purposes is a bigger issue than other environmental issues. Industrialization and Urbanization have even polluted rainwater. In China, when it rains, rainwater is stored on the roof or other sources of storage for daily use resulting in pollution. Several studies have been conducted to treat rainwater. The objective of this study is to evaluate the efficiency of constructed wetlands by using ACF as a medium. So, this study aims to treat rainwater in Wuhan city through a Composite Vertical Flow Constructed Wetlands. First, rainwater was stored in the tank while it flows out of the roof, further it is processed in constructed wetlands. The constructed wetlands is consisted with plants Calamus and Chives, adding ACF (prepared from luffa) has achieved great results in this study. Results show that the pollutants have been removed to a considerable level, there were significant differences in removal rates under different HRT at 6h, 9h and 12h respectively. Therefore, Composite Vertical Flow Constructed Wetlands is recommended for total nitrogen and Ammonia nitrogen and total phosphorus.

• Journal of Environmental Science International
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• v.29 no.3
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• pp.299-306
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• 2020

This study analyzed the changes in the concentrations of the pollutants of constructed treatment wetlands which come from the discharge water of a sewage treatment plant. According to the results of budgets in constructed wetlands, the net production of the organic carbon, nitrogen and phosphorus were 368 kgC/month, 306 kgN/month and -49 kgP/month, respectively. The high particle form of pollutants are mostly removed due to settlement and absorption when passing through wetlands, but because a low processing efficiency for pollutants was shown when sewage treatment plant wastewater flows in, there is a need for a water management system that can reduce the organic matter load through monitoring. The low removal efficiency of constructed wetlands were caused by both structural and operational problems. Therefore, to enable to play a role as a reduction facility of pollutants, an appropriate design and operation manuals for constructed wetlands is urgently needed.

• Membrane and Water Treatment
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• v.11 no.4
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• pp.313-321
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• 2020

ACF preparation from different materials and its application in constructed wetlands for wastewater treatment has been focused in environmental field. Different materials have been used to prepare ACF around the world. This study aims to prepare, characterize and use of ACF from loofah for removal of Tetracycline from water through composite vertical flow constructed wetlands. ACF was prepared and it was tested for characterization, later it was used for removal of Tetracycline from water through composite vertical flow constructed wetlands. In composite vertical flow constructed wetlands, three HRTs were set according to the experiment, 1D, 2D, and 3D is individually. Samples were transported immediately from collection point to laboratory for analyzing. Samples were measured for Tetracycline (TC), Total Phosphorus (TP), and Total nitrogen and COD. Tetracycline absorbance with respective 356nm was obtained good and HRT is important factor. Results show that composite vertical flow constructed wetlands with ACF from luffa is best option and it is recommended to study further deep analysis.

• Journal of Wetlands Research
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• v.23 no.3
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• pp.242-251
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• 2021

Surface water pollution is a serious environmental problem in developing countries, like India, due to the unregulated discharge of untreated wastewater. To overcome this, the constructed wetlands (CWs) have been proven to be an efficient technology for wastewater treatment. In this study, different existing and experimental facilities were reviewed to be able to determine the current status of constructed wetlands in India. Based on the collected data from published literature, industrial wastewater contained the highest average chemical oxygen demand (COD), biochemical oxygen demand (BOD). In terms of total nitrogen (TN), Total phosphorous (TP), the lowest concentration was found on domestic wastewater. Vertical flow constructed wetlands (VFCW) and Horizontal flow constructed wetland (HFCW) were more effective in removing TSS, BOD, TP in domestic and industrial wastewater, whereas hybrid constructed wetlands (HCW) showed the highest removal for COD. The use of constructed wetlands as advanced wastewater treatment facilities in India yielded better water quality. The treatment of wastewater using constructed wetlands also enabled further reuse of wastewater for irrigation and other agricultural purposes. Overall, this study can be beneficial in evaluating and promoting the use of constructed wetlands in India.

• Journal of Wetlands Research
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• v.7 no.3
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• pp.33-39
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• 2005

Constructed wetlands are considered as an important tool for wastewater treatment, wastewater management and flooding control. In addition, one of the most promising technologies for application in many countries seems to be constructed wetlands due to their properties such as utilization of natural processes, simple construction, operation and maintenance, process stability, cost effectiveness, etc. This research is performed to find the possibility for treating livestock wastewater using a constructed wetland. The removal efficiencies of CODcr, TN, TP, SS, and color were 97.9%, 97.8%, 97.2%, 99.1%, and 84.9%, respectively. In particular, SS was completely removed. In conclusion, constructed wetlands could be applied to livestock wastewater treatment. Further, it needs time for stabilization to reduce the pollutants accumulated in soil.