Wetlands For Wastewater Treatment Research Articles

Potential Use and Challenges of Constructed Wetlands for Wastewater Treatment and Conservation in Game Lodges and Resorts in Kenya.

Constructed wetlands are cost-effective wastewater treatment alternatives that receive worldwide acceptance. For the Kenyan hospitality industry, in particular, constructed wetlands (CWs) provide opportunities for wastewater reuse and recovery of resources, as well as improvements in local environmental conditions. Hospitality establishments produce large volumes of wastewater that is sometimes discharged to the environment without being treated. This is not only harmful to communities living downstream of these rivers but also to the flora and fauna which are the main attraction for most who visit these lodges. This study used qualitative methods to collect and analyze published official government documents, peer-reviewed research articles, and professional reports including leading international and Kenyan case studies to explore how constructed wetlands can be effectively used in game lodges and resorts situated in arid and remote areas of Kenya. The study investigated wastewater management systems adopted by remote game lodges and resorts in Kenya and the potential role, as well as the challenges to adopting constructed wetland (CW) technology. The results indicated that hotels, game lodges, and resorts both internationally and locally are adopting different types of CWs including surface and subsurface flow as alternative nature-oriented wastewater management systems. The study identified opportunities in the use of CWs as a wastewater management and conservation strategy. The results suggest that there are potential challenges which include inadequate expertise and technical support; low volume of discharge during off-seasons; limited space or land; and the attitude of hospitality managers towards constructed wetlands. Based on these preliminary findings, one may conclude that game lodges, ecolodges, and resorts in remote areas are prime candidates for constructed wetland establishment. The study makes specific recommendations with implications for policy and practice to promote sustainable hospitality operations and environmental conservation. It is suggested that future studies test the efficacy and efficiency of CW technology as wastewater management systems in the Kenyan wilderness areas including national parks, game reserves, and forests.

Oxygen Transfer Capacity as a Measure of Water Aeration by Floating Reed Plants: Initial Laboratory Studies

Reed-Phragmites australis (Cav.) Trin. ex Steud, an aquatic plant, commonly used in constructed wetlands for wastewater treatment, supplies oxygen into the subsurface environment. Reed may be used as a ‘green machine’ in the form of a floating vegetation cover with many applications: wastewater lagoons, manure lagoons or sewage sludge lagoons. An important measure of the performance of the plant system is the oxygen transfer capacity (OTC). Accurate prediction of the OTC in relation to reed biomass would be crucial in modelling its influence on organic matter degradation and ammonia–nitrogen oxygenation in such lagoons. Laboratory experiments aiming to determine OTC and its dependence on reed biomass were carried out. Eight plants with a total dry mass ranging from approximately 3 to 7 g were tested. Mean OTC was determined per plant: 0.18 ± 0.21 (g O2·m−3·h−1·plant−1), with respect to leaves-and-stem dry mass (dlsm): 44.91 ± 35.21 (g O2·m−3·h−1·g dlsm−1), and to total dry mass (dtm): 33.25 ± 27.97 (g O2·m−3·h−1·g dtm−1). In relation to the relatively small root dry mass (drm), the OTC value was 136.02 ± 147.19 (g O2·m−3·h−1·g drm−1). Measured OTC values varied widely between the individual plants (variation coefficient 115%), in accordance with their differing size. Oxygenation performance was greatest in the reed plants with larger above ground dry mass (>4 g dlsm), but no influence of the root dry mass on the OTC rate was found.

Potential of aquatic weeds to improve water quality in natural waterways of the Zambezi catchment

One prominent effect of nutrient pollution of surface waters is the mass invasion of floating plants, which can clog waterways, disrupting human use of aquatic systems. These plants are widely vilified and motivate expensive control campaigns, but their presence may be providing a poorly recognized function in the cycling of excess nutrients. The capacity for floating plants to absorb nutrients from surface water has been understood for decades, primarily from their use in constructed wetlands for wastewater treatment. Yet, in natural settings, there has not been to date any effort to quantify whether floating plant invasions represent important pools or fluxes of nutrients relative to those of the river catchments in which they occur. We found that seasonal hydrologic cycles in the Zambezi trap and flush floating plants from river choke points, such as dams and river confluences, on an annual basis. Peak plant biomass at such choke points constitutes a proxy for estimating annual plant-bound nutrient loads. We assessed the significance of floating vegetation as nutrient sinks by comparing annual plant-bound nutrient loading to conventional river nutrient loading (dissolved and particulate) for four tributaries of the Zambezi River in Zambia. We found that the relative importance of floating vegetation was greatest in the more urbanized catchments, such as the Maramba River draining the city of Livingstone, representing approximately 30% and 9% of annual digestible phosphorus and nitrogen flux respectively. We also found plant-bound phosphorus to be important in the Kafue River (19%), draining the industrial town of Kafue and extensive sugarcane plantations. These results demonstrate the great potential of floating plants to take up excess nutrients from natural river systems. Given the importance of hydrology in the life cycle of floating vegetation, controlled dam discharges may have an important role in managing them and their water quality treatment functions.

Carbon footprint of constructed wetlands for winery wastewater treatment

The aim of this study was to estimate the carbon footprint (CFP) of constructed wetlands for winery wastewater treatment. In particular, a constructed wetland scenario was compared to the previous scenario (third-party management) and to an activated sludge system. CFP considered both indirect and direct greenhouse gas (GHG) emissions measured on-site. Moreover, an economic analysis of the considered scenarios was also addressed. The results showed that the constructed wetland scenario had the lowest CFP (1.2 kg CO2eq mwater−3), while the third-party management was the worst scenario (52 kg CO2eq mwater−3) followed by the activated sludge system (4.5 kg CO2eq mwater−3). This was mainly due to the high GHG emissions generated by wastewater and sludge transportation as well as chemicals and electricity consumption in the third-party and activated sludge scenarios compared to the constructed wetlands. In terms of costs, the constructed wetland system was shown to be a low-cost technology which would reduce the capital, operation and maintenance costs associated with winery wastewater treatment up to 50% and 98%, respectively. Finally, constructed wetlands are low-cost and environmentally friendly technologies which constitute a sustainable alternative to conventional solutions for winery wastewater treatment.

Horizontal subsurface flow constructed wetland for tertiary treatment of dairy wastewater: Removal efficiencies and plant uptake

There are different physicochemical and biological methods to treat effluents. However, their efficiency is not enough to meet the effluents discharge limits. For this reason, it could be possible to employ a polished treatment. A suitable alternative for this goal could be constructed wetlands (CWs). The aim of the present research was to evaluate contaminants removal efficiency of a pilot scale horizontal subsurface flow constructed wetland (HSSFW) for tertiary treatment of dairy wastewater. A vegetation study was also conducted in order to determine the role of plants on nutrient removal. A pilot scale HSSFW planted with Typha domingensis was built in a dairy factory, after the biological treatment. The substrate used was river gravel. During a seven-month research period, thirty-two samples (influent and effluent) were taken and analyzed to determine physicochemical and microbiological parameters as well as removal efficiencies. Biomass, TP, TKN and organic matter content in plants was determined at the beginning and end of the monitoring period. Suspended solids showed significant differences between inlet and outlet, with a mean removal efficiency of 78.4%. For BOD and COD, mean removal efficiencies were respectively 57.9 and 68.7%. Removal percentages for TKN, Nitrates and TP were lower than other parameters (25.7%, 47.8% and 29.9%, respectively). Fecal Coliform bacteria decreased one order of magnitude in final effluent. In the case of Escherichia coli and Pseudomona aeruginosa results were variable. Total biomass increased 4.6 times at the end of the monitoring period. The study of plants indicated its important contribution in terms of contaminant uptake and retention. HSSFW would be an advisable alternative as a tertiary treatment of dairy wastewater.

Removal of nutrients in constructed wetlands for wastewater treatment through plant harvesting – Biomass and load matter the most

Uptake of nutrients as a removal process in constructed wetlands with horizontal subsurface flow (HF CWs) treating municipal wastewater is usually considered negligible. However, there is very low number of results which would confirm this assumption. The amount of nutrients sequestered in the aboveground biomass, and thus available for harvesting, is called standing stock and it is determined by both nutrient concentration in the biomass and biomass itself. The common values of standing stock vary in the range of 30–80 g N m−2 and 2–6 g P m−2 while inflow loadings of municipal wastewater are around 950 g N m−2 yr−1 and 350 g P m−2 yr−1. Under these conditions, the standing stock represents less than 10% of the nitrogen load and 5% of phosphorus load. Removal of nitrogen and phosphorus in HF CWs is usually low and therefore, the percentage of removed load by plant uptake is higher. Under the conditions of low loadings, i.e., less that 500 (200) g N m−2 yr−1 or 100 (50) g P m−2 yr−1, the portion of removed nitrogen or phosphorus could be substantially higher. In our study, the combination of high standing stocks (> 100 g N m−2 and 10 g P m−2) supported primarily by high plant biomass and low inflow loadings was responsible for removal of up to 62% of nitrogen and 58% of phosphorus. The results of our study carried out in four HF CWs in the Czech Republic indicate that the direct role of plants in nutrient removal in HF CWs may be underestimated especially under conditions of low inflow loading and high plant biomass.

Pilot-scale constructed wetlands for swine wastewater treatment: Microbial community analysis in bacterioplankton and epiphyton and options for resource recovery

In this study, the abundance and structure of bacterial and denitrifying functional genes of epiphyton and bacterioplankton in pilot-scale surface flow constructed wetlands treating different ammonium nitrogen concentrations (∼0.2, 40, 170, and 230 mg/L) of swine wastewater were investigated by quantitative PCR. The gene abundance of denitrifiers in epiphyton outnumbered the gene abundance of denitrifiers in bacterioplankton (p < 0.01), e.g., nirK gene abundance: 1.6–4.5 × 107vs 0.23–1.5 × 104 copies/ng DNA. A nitrogen concentration-dependent microbial community structure was observed for epiphyton and bacterioplankton. Proteobacteria, Bacteroidetes, and Actinobacteria dominated at the phylum level in both epiphyton and bacterioplankton. The nirS gene abundance in both niches was negatively related to the dissolved oxygen and redox potential of wastewater, but it was positively related with the Bacteroidetes and Flavobacterium abundance. The results indicated that microbial community structure and abundance are distinct between epiphyton and bacterioplankton. This study also demonstrate that epiphytic biofilms play an important role in denitrification during the treatment of swine wastewater in constructed wetlands. Finally, since swine wastewater serves as an excellent source for nutrients, possible technological options including periphyton techniques for resource recovery from wastewater and future research prospective have been suggested.

Greenhouse Gas Emissions From a Horizontal Subsurface Flow Constructed Wetland for Wastewater Treatment in Small Villages

&lt;p&gt;Constructed wetlands with a land-intensive, low energy and less operational requirement have been used as a sustainable green technology for treating wastewaters. But are constructed wetlands sustainable? The objectives of the present study are to evaluate one year monitored horizontal subsurface flow constructed wetland’s treatment efficiency from May 2017 to May 2018 and to estimate the greenhouse gas emissions (GHG) in terms of N2O and CH4. As field data show the average removal efficiencies are low but are all within the effluent standard for water quality. One year average of high suspended solids (91.1 %), high total nitrogen (%85.6), low total phosphorous (22.4% TP), low organic matter (43.1% BOD5 &amp;amp; 35.9% COD) removals are obtained. One year average methane and nitrous oxide emissions at the outlet of constructed wetland are calculated as 17.52 and 0.29 kg/d, respectively.&lt;/p&gt;&#x0D;

Application of constructed wetland for advanced treatment of industrial wastewater

An experimental study to use a pilot vegetated submerged bed (VSB) wetland for the advanced treatment of effluent from the central wastewater treatment plant (CWWTP) of an industrial zone was carried out. The pilot VSB wetland included reeds (Phragmites australis), cattail (Typha orientalis), and blank cells in parallel. The constructed wetland was observed to be a suitable measure for wastewater reuse via the high performance of organic matter, turbidity removal, and detoxification. At loading rates of up to 250 kg chemical oxygen demand (COD) ha-1d-1, both cells with emergent plants obtained high efficiency of contaminant removal. Suspended solids (SS) and turbidity removal reached 67-86% and 69-82%, respectively. The COD removal efficiencies of the reed and cattail cells at a loading rate of 130 kg COD ha-1d-1were 47 and 55%, respectively. At a high loading of 400 kg COD ha-1d-1, the toxicity unit (TU) reduced from 32-42 to 4.9 and 4.2 in the effluent of the cattail and reed cells, respectively. Especially at loadings of 70, 130, and 185 kg COD ha-1d-1, the effluent TU was less than 3.0, corresponding to a non-toxic level to the ecosystem. The effluent quality met industrial or landscaped wastewater reuse at these loading rates.

Constructed Wetlands for Sustainable Wastewater Treatment in Hot and Arid Climates: Opportunities, Challenges and Case Studies in the Middle East

Many countries and regions around the world are facing a continuously growing pressure on their limited freshwater resources, particularly those under hot and arid climates. Higher water demand than availability led to over-abstraction and deterioration of the available freshwater resources’ quality. In this context, wastewater, if properly treated, can represent a new water source added in the local water balance, particularly in regions of Colorado, California, Australia, China and in the wide region of the Middle East, which is characterized as one of most water-stressed regions in the world. This article summarizes the status of wastewater treatment and management in the Middle East and discusses the challenges, the various barriers and also the opportunities that arise by introducing the sustainable technology of Constructed Wetlands in the region. Furthermore, the aim of the article is to provide a better insight into the possibility and feasibility of a wider implementation of this green technology under the hot and arid climate of Middle East by presenting several successful case studies of operating Constructed Wetlands facilities in the region for the treatment of various wastewater sources.

Evaluating the efficiency of Cyperus alternifolius on constructed wetland for the domestic wastewater treatment in the peri-urban area of Northern Vietnam

Constructed wetland (CW) is an ecological work that can treat wastewater in natural condition. Combining CW with other ecological wastewater treatment works can create a suitable low-cost treatment system for peri- urban areas. The climatic conditions in the Northern region are favorable for the growth of Cyperus alternifolius, one of the commonly planted tree in HFCW worldwide. Our study focuses on the growth of Cyperus alternifolius on HFCW to evaluate the removal efficiency of organic substances and nutrients (BOD5, N-NH4, N-NO3, P-PO4). The dynamical coefficients of decomposition of those matters were also identified. This research employed a wastewater treatment pilot with HFCW planted Cyperus alternifolius and other ecological facilities in a peri-urban area in the North of Vietnam. It was found out that Cyperus alternifolius grew well with a high growth rate. The growth of Cyperus alternifolius enhanced the conversion of organic substances (BOD5) and nutrients (NH4, NO3, PO4) with high decomposition kinetic coefficients. The kinetic coefficient (kBOD) of HFCW in this research was 0.214md−1 which is much higher than the recommendation of Design Standard TCVN 7957:2008. Domestic wastewater after being treated through CW satisfied level A of National technical regulation on domestic wastewater QCVN 14:2008/BTNMT.

TREATMENT EFFICIENCY OF PIGGERY WASTEWATER BY SURFACE AND HORIZONTAL SUBSURFACE FLOW CONSTRUCTED WETLANDS

Constructed wetlands have been used to treat various types of wastewaters such as urban runoff, acid mine drainage, municipal, industrial, and livestock wastewaters. This study is conducted to evaluate the effectiveness of two constructed wetlands (surface and horizontal subsurface flows) for piggery wastewater treatment after biogas process. The wetland plant Phragmites australis Cav. was used in 45 days for the experiments. The CWs were designed to treat up to 100 liters/day with the hydraulic retention time (HRT) of 3 days. Parameters including pH, COD, TSS, NH4+-N, total nitrogen (TN) and total phosphorus (TP) were measured. The pH of the CWs system was in the range of 6.7 to 7.3. The results showed that the horizontal subsurface flow CW had better treatment performance compared to the surface flow system. The removal efficiency of TP, TSS, COD, TN and NH4+-N by surface flow CW was 80, 60, 66, 60 and 65%, respectively while those by horizontal subsurface flow system was 86, 78, 74.6, 67.1 and 74.2%, respectively. The water quality of the effluents of both two CWs met the Vietnamese standards for livestock wastewater (QCVN62/2016-BTNMT, column B).

Influence of Phragmites communis and Zizania aquatica on rhizosphere soil enzyme activity and bacterial community structure in a surface flow constructed wetland treating secondary domestic effluent in China.

The present study aims to investigate the effects of Phragmites communis and Zizania aquatica on rhizosphere soil enzyme activity and bacterial community structure in a surface flow constructed wetland (SFCW) for the treatment of domestic sewage from the Shanxi province of China. The basic physical and chemical properties of the soil, the contents of soil urease (UE), alkaline phosphatase (ALP), soil microbial biomass carbon and nitrogen (SMBC, SMBN), and bacterial community structure were measured in the Phragmites communis group (PG), Zizania aquatica group (ZG), and control group (CG), respectively. The results showed that (1) the contents of UE, ALP, SMBC, and SMBN in rhizosphere soil of PG were more than those of ZG; (2) the highest bacterial abundance and α-diversity appeared in PG, in which Gp6 was the most abundant bacterial genus in PG; (3) the main functions of the dominant bacteria Gp6 and Longilinea in PG were involved in metabolizing multiple carbohydrates and participating in the carbon cycle in the soil based on the clusters of orthologous groups pathway analysis data; (4) the bacterial community of PG was mainly affected by the positive correlation with arsenic, nickel, or SMBC via the redundancy analysis. Collectively, Phragmites communis is a recommended species for wastewater wetland treatment system in Shanxi province, and the special enzymes and dominant bacteria in plant rhizosphere soil had obvious functions of removing organic pollutants. Besides, the influences of environmental factors on rhizosphere bacteria and the combined effects of Phragmites communis and dominant bacteria in wetland wastewater treatment system should be taken seriously.

Changes of substrate microbial biomass and community composition in a constructed mangrove wetland for municipal wastewater treatment during 10-years operation

Constructed wetlands (CWs) have been used for wastewater treatment for decades, but research on microorganisms involved, especially long-term changes, is still limited. In this study, we evaluated changes in the substrate microbial community in a pilot-scale horizontal subsurface-flow constructed mangrove wetland during 10-years operation. In the 3rd year of operation, microbial biomass carbon and phospholipid fatty acids (PLFAs) reached peak values in two vegetated belts planted with Aegiceras corniculatum (Ac) and Kandelia obovata (Ko), respectively, then stabilized or declined in the 9th and 10th years of operation. PLFA profiles reflecting microbial community compositions varied significantly in the Ac belt during the operation period. Principal component (PCA) and redundancy analyses (RDA) revealed that microbial community compositions were significantly correlated with organic matter content, especially in the 9th and 10th years of operation, implying that the substrate microbial community in constructed mangrove wetland is sensitive to substrate characteristics and can be used as an indicator for long-term performance of CWs.

Potential Application of Chilean Natural Zeolite as a Support Medium in Treatment Wetlands for Removing Ammonium and Phosphate from Wastewater

This study aims to evaluate the sorption characteristics of NH 4 + -N and PO 4 3 − -P onto the surface of natural zeolites coming from Chile and their potential application in the subsurface-flow treatment wetlands for wastewater treatment in rural areas. For this purpose, adsorption experiments onto the zeolite were developed in batch assays. The effects of the adsorbent quantity (20 g and 50 g) and particle size (0.2–1.0 mm; 1.5–3.0 mm, and 5.0–8.0 mm) were evaluated in terms of adsorption capacity at different NH4+-N and PO4−3-P concentrations. Then, the obtained laboratory results were adjusted to theoretical models: Saturation-growth-rate and Langmuir. The saturation adsorption of NH4+-N on the zeolite increases at the same time that the initial concentration increases for the same zeolite quantity; however, the saturation values were similar between the different zeolite sizes tested. For PO4−3-P, the adsorption did not have a direct relationship with the initial concentration nor zeolite quantity and better results were only achieved for zeolite sizes of 1.5–3.0 mm. Regarding the Langmuir model, sizes of 1.5–3.0 mm had the best adsorption characteristics, with the maximum adsorption capacity of up to 1.58 mg/g for NH4+-N and up to 0.08 mg/g for PO4−3-P. Therefore, a new material—a natural zeolite from the Maule Region of Chile—is described as a potential support medium for treatment wetlands.

A novel integrated bio-reactor of moving bed and constructed wetland (MBCW) for domestic wastewater treatment and its microbial community diversity

ABSTRACT An MBBR and CW combo bio-reactor (MBCW) was designed as a novel hybrid process for simultaneous organic, nitrogen and phosphate removal through the long-term operation. The effect of the internal recycling rate (IRR), hydraulic retention time (HRT) and chemical oxygen demand/total nitrogen (C/N) ratio were all discussed, and the recommended values were 5:1, 12 h and >6, respectively. A higher C/N ratio was a key factor for achieving a higher TN removal. The mixed biocarrier system was realized by inoculating porous polymer carriers (PPC) and cylindrical polyethylene carriers (CPC) and achieving a higher organic biodegradation and nitrification rate compared to a single carrier system. Microorganism activities and plants’ uptake or utilization both contributed to the nutrient removal in a constructed wetland. High-throughput sequencing results revealed an abundant microbial diversity and a distinct microbial distribution in the whole system where Flavobacterium (14.2%), Acinetobacter (12.87%) and Rhodobacter (10.83%) dominated on PPC, Terrimonas (8.88%), Reyranella (6.61%) and Rubinisphaera (5.63%) dominated on CPC, Comamonas (4.18%), Gemmobacter (4.02%) and Hydrogenophaga (3.97%) dominated on CWs, as well as Citrobacter (53.13%) on suspended floc.

The Use of Sub- Surface Constructed Wetlands for Wastewater Treatment in Cold Arid Climate

The Use of Sub- Surface Constructed Wetlands for Wastewater Treatment in Cold Arid Climate

Variation in contaminant removal efficiency in free-water surface wetlands with heterogeneous vegetation density

The interaction between flow and vegetation in constructed wetlands plays a major role in determining wetland performance. In this study, a two-dimensional depth-averaged model was used to simulate flow, mass transport and contaminant removal in a conceptual free-water surface (FWS) wetland with heterogeneous vegetation patterns. The main objectives of this study were (1) to quantify the effectiveness of FWS wetlands with different vegetation patterns in reducing pollutant load, and (2) to identify optimal vegetation distributions that maximize contaminant removal. Simulations were performed for different random vegetation fields characterized by imposed mean, variance and correlation lengths of stem density. The wetland was assumed to receive water from a stream and to deliver it back to the same stream according to an imposed head drop. The simulations show that the concentration reduction efficiency increases monotonically with average stem density, whereas mass removal has a peak for an intermediate value of average stem density. The ensemble average of the total mass removal decreases for increasing stem density variance and correlation length, because the presence of vegetation patches with significantly different stem density promotes preferential flow paths. Preferential flow paths parallel to the mean flow direction were found to reduce the hydraulic efficiency of wetlands by producing short-circuiting, whereas, for the same mean stem density, alternating stripes of stem density perpendicular to the flow direction provided higher concentration and mass reduction. By providing a quantitative understanding of the impact of spatial vegetation heterogeneity, the results provide useful guidelines for design and maintenance of constructed wetlands for wastewater treatment.

Effectiveness of Solar Driven Anodic Oxidation and Uv Methods for Disinfection of Municipal Wastewater in India

This paper presents the performance of the two disinfection methods experimented at a pilot scale level as part of an integrated treatment system involving Anaerobic Digestion (UASB Process) followed by the Constructed Wetlands (CW) for municipal wastewater treatment under Indian conditions. The disinfection methods were installed in parallel at a pilot scale levels involving solar driven Anodic Oxidation (AO) and Ultra-violet (UV). The systems were implemented within the Indo-Euro Research Project “SWINGS” at three places in India namely, Aligarh, Kalyani and Amarkantak, with aim to develop / deploy sustainable wastewater management. This study mainly focused on three microbial groups, total coliforms (TC), fecal coliforms (FC) and E-coli. Both the systems, AO and UV were operated at a very less energy demand. This was in the range 0.25 to 0.30 kWh/m3. The energy requirements was met with the help of roof top solar panels. The raw municipal wastewater contained TC, FC and E. coli in the range of 105 to 107 CFU/100ml. It was found that about 3-log unit indicator organisms were removed in the UASB &amp; CWs. The effluent of CWs were equally fed to the two parallel disinfection systems, AO and UV. Results indicate that UV has shown better performance. The final effluent of AO contains average (TC 42.0±39.2, FC 16.1±13.2, E-coli 5.6±6.3) CFU/100 ml whereas UV effluent was TC 6.6±4.1, FC 1.2±1.0, E-coli 0.1 ±0.3 CFU/100 ml. The study concludes that solar driven disinfection systems like AO and UV are very effective for small flow rates and offers a promising way to energy scarce regions or in remote areas.

Research on perfermance improvement of constructed wetland wastewater treatment system

Constructed wetland is a kind of wastewater ecological treatment technology. It has the advantages of low investment, convenient operation and management, stable water quality, and has certain landscape effects. Therefore, it is widely used in the field of wastewater treatment. However, this technology still has certain problems in practical engineering applications, such as irregular design and clogging, resulting in limited service life and processing performance of the wetland. The type selection of constructed wetlands, matrix type and particle size, plant type and configuration, and water inflow mode and operating parameters are the main factors affecting the operating life and purification effect of constructed wetlands. Based on the author’s practice, the article introduces in detail the current process structure, basic design methods and economic and technical comparison of constructed wetland wastewater treatment for reference by relevant scientific research and design units.