Effect of the Structure of Composite Ecological Floating Bed on Eutrophic Pollutants Removal in Water

2014 ◽  
Vol 1073-1076 ◽  
pp. 755-758 ◽  
Author(s):  
Gong Di Xu ◽  
Jin Zhao Hu ◽  
Te Mu Le Gang ◽  
Rui Na Liu ◽  
Meii Yu Wu ◽  
...  
Keyword(s):  
Domestic Sewage ◽  
Pollutant Removal ◽  
Removal Rates ◽  
Pollutants Removal ◽  
Static Conditions

By applying the technology of composite ecological floating bed, a research was conducted to compare the eutrophic pollutant removal effects in domestic sewage among different filler proportions under static conditions. The results of proportion comparison experiments showed that the proportion of Plant: Filler = 1:1 had the best effects on NH4+-N with the average removal rates as 97.93%, while as Plants: Filler = 1:1/2 had the best effects on TN and TP with the average removal rates of 89.05% and 91.55% respectively.

Influence of Pollutant Removal Efficiency on Natural Ventilation in GPPLF System

2013 ◽  
Vol 448-453 ◽  
pp. 468-471
Author(s):  
Xiao Bo Zhou ◽  
Cheng Duan Wang ◽  
Zhi Shuai Wang ◽  
Li Li Zhang ◽  
Xia Li
Keyword(s):  
Removal Efficiency ◽  
Treatment Effect ◽  
Natural Ventilation ◽  
Domestic Sewage ◽  
T Test ◽  
Pollutant Removal ◽  
Removal Rates ◽  
Hydraulic Loading ◽  
Perforated Pipe ◽  
Pollutant Removal Efficiency

Two Gravel-less Perforated Pipe Leach Fields systems with naturally ventilated or not were tested to treat domestic sewage under the hydraulic loading of 3.3 cm/d, and the differences of the two systems decontamination effect were also investigated by using T test. The results showed that the average removal rates of CODCr, TP, TN and turbidity were 86.1%, 58.0%, 61.1% and 93.6% in the naturally ventilated system, which was 2.0%, 5.4%, 10.2% and 3.2% higher than the normal GPPLF system under the same operating condition. T test indicated that the system of natural ventilation had little effect on removal of CODCr and TP, but could significantly improve the treatment effect of TN and turbidity.

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

2015 ◽  
Vol 71 (9) ◽  
pp. 1333-1339 ◽  
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.

Mechanisms of High Efficiency and Stabilization of Baffled Constructed Wetland in Treatment of Domestic Sewage

2013 ◽  
Vol 295-298 ◽  
pp. 1057-1061 ◽  
Author(s):  
Chang Bing Ye ◽  
Zhi Ming Zhou ◽  
Ke Zhao ◽  
Qin Liu
Keyword(s):  
Constructed Wetland ◽  
Removal Rate ◽  
Short Circuit ◽  
Domestic Sewage ◽  
Wetland Plants ◽  
Stable Operation ◽  
Removal Rates ◽  
Operational Life ◽  
High Efficient ◽  
Hydraulic Load

To solve the problem of short-circuit of individual current constructed wetland, a baffled constructed wetland was designed and applied to treat domestic sewage by our research group. The wetland plants were composed of Eichhormia crassipes, Oenanthe javanica, Cyperusalternifolius, Phragmites communis and Aquatic. The results of 18 month indicated that the optimal hydraulic load of baffled constructed wetland was 2.0~2.2 m3/(m2•d). At the hydraulic load of 2.0m3/(m2•d), the COD, TN and TP removal rates of baffled constructed wetland could be over 76.40%, 76.12%, 65.37%, respectively, at 24°C. When the temperature decreased to 12°C, the COD, TN, TP removal rates of system decreased to 67.56%、62.75% and 61.33%, respectively; The SS removal rate of the first 6 compartments was about 79.5% and that of system could maintain 87.18% during the operation of system. Based on the results of trial, the mechanisms of extending the baffled constructed wetland's operational life was owed to high efficient SS removal rate of the first 6 compartments which was used as constructed wetland and anaerobic baffled reactor (ABR). As a result, the long-term stable operation of system in treatment of domestic sewage was explained with extending about 5 times service life than that of individual current constructed wetland. The mechanisms of higher efficiency of baffled constructed wetland in treatment of domestic sewage were owed to the longer flow line of system and the up-down flow of domestic sewage makes pollutant more intimate contact with roots of wetland plants.

scholarly journals Improving the Treatment Performance of Low Impact Development Practices—Comparison of Sand and Bioretention Soil Mixtures Using Column Experiments

Water ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1210
Author(s):  
Abtin Shahrokh Hamedani ◽  
Arianne Bazilio ◽  
Hanieh Soleimanifar ◽  
Heather Shipley ◽  
Marcio Giacomoni
Keyword(s):  
Phosphorus Removal ◽  
Low Impact Development ◽  
Pollutant Removal ◽  
Control Measures ◽  
Column Experiments ◽  
Removal Rates ◽  
Treatment Performance ◽  
Soil Mixtures ◽  
Limestone Sand ◽  
The Impact

Low impact development (LID) practices, such as bioretention and sand filter basins, are stormwater control measures designed to mitigate the adverse impacts of urbanization on stormwater. LID treatment performance is highly dependent on the media characteristics. The literature suggests that bioretention media often leach nutrients in the stormwater effluent. The objective of this study was to analyze the treatment performance of different sand and bioretention soil mixtures. Specifically, this investigation aimed to answer whether the use of limestone and recycled glass could improve the treatment performance of bioretention systems. Column experiments were designed to assess (1) the removal efficiencies of different sand and bioretention soil mixtures and (2) the impact of plant uptake on removal rates. Enhanced pollutant removal was observed for the custom blends with addition of limestone sand, indicating mean dissolved and total phosphorus removal of 44.5% and 32.6% respectively, while the conventional bioretention soil mixtures leached phosphorus. Moreover, improved treatment of dissolved and total copper was achieved with mean removal rates of 70.7% and 93.4%, respectively. The results suggest that the nutrient effluent concentration decreased with the addition of plants, with mean phosphorus removal of 72.4%, and mean nitrogen removal of 22% for the limestone blend.

scholarly journals A Mini Review on Bismuth-Based Z-Scheme Photocatalysts

Materials ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5057
Author(s):  
Ruizhen Li ◽  
Hanyang Chen ◽  
Jianrong Xiong ◽  
Xiaoying Xu ◽  
Jiajia Cheng ◽  
...  
Keyword(s):  
Environmental Pollutants ◽  
Co2 Reduction ◽  
Pollutant Removal ◽  
Energy Utilization ◽  
Research Progress ◽  
Future Perspective ◽  
Synthesis Methods ◽  
Pollutants Removal ◽  
Photocatalytic Reactions ◽  
Redox Ability

Recently, the bismuth-based (Bi-based) Z-scheme photocatalysts have been paid great attention due to their good solar energy utilization capacity, the high separation rate of their photogenerated hole-electron pairs, and strong redox ability. They are considerably more promising materials than single semiconductors for alleviating the energy crisis and environmental deterioration by efficiently utilizing sunlight to motivate various photocatalytic reactions for energy production and pollutant removal. In this review, the traits and recent research progress of Bi-based semiconductors and recent achievements in the synthesis methods of Bi-based direct Z-scheme heterojunction photocatalysts are explored. The recent photocatalytic applications development of Bi-based Z-scheme heterojunction photocatalysts in environmental pollutants removal and detection, water splitting, CO2 reduction, and air (NOx) purification are also described concisely. The challenges and future perspective in the studies of Bi-based Z-scheme heterojunction photocatalysts are discussed and summarized in the conclusion of this mini review.

scholarly journals Graphene-Modulated Removal Performance of Nitrogen and Phosphorus Pollutants in a Sequencing Batch Chlorella Reactor

Materials ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2181 ◽  
Author(s):  
Gonghan Xia ◽  
Wenlai Xu ◽  
Qinglin Fang ◽  
Zishen Mou ◽  
Zhicheng Pan
Keyword(s):  
Optical Microscopy ◽  
Sewage Treatment ◽  
Ammonia Nitrogen ◽  
Pollutant Removal ◽  
Plate Count ◽  
Nitrogen And Phosphorus ◽  
Removal Rates ◽  
Practical Support ◽  
Plate Count Method ◽  
The Impact

In this work, the influence of graphene on nitrogen and phosphorus in a batch Chlorella reactor was studied. The impact of graphene on the removal performance of Chlorella was investigated in a home-built sewage treatment system with seven identical sequencing batch Chlorella reactors with graphene contents of 0 mg/L (T1), 0.05 mg/L (T2), 0.1 mg/L (T3), 0.2 mg/L (T4), 0.4 mg/L (T5), 0.8 mg/L (T6) and 10 mg/L (T7). The influence of graphene concentration and reaction time on the pollutant removal performance was studied. The malondialdehyde (MDA) and total superoxide dismutase (SOD) concentrations in each reactor were measured, and optical microscopy and scanning electron microscopy (SEM) characterizations were performed to determine the related mechanism. The results show that after 168 h, the total nitrogen (TN), ammonia nitrogen (AN) and total phosphorus (TP) removal rates of reactors T1–T7 become stable, and the TN, AN and TP removal rates were gradually reduced with increasing graphene concentration. At 96 h, the concentrations of both MDA and SOD in T1–T7 gradually increased as the graphene concentration increased. In optical microscopy and SEM measurements, it was found that graphene was adsorbed on the surface of Chlorella, and entered Chlorella cells, deforming and reducing Chlorella. Through the blood plate count method, we estimated an average Chlorella reduction of 16%. According to the water quality and microscopic experiments, it can be concluded that the addition of graphene causes oxidative damage to microalgae and destruction of the Chlorella cell wall and cell membrane, inhibiting the nitrogen and phosphorus removal in Chlorella reactors. This study provides theoretical and practical support for the safe use of graphene.

scholarly journals Purification efficiency of zeolite and two planted grasses on sewage and relationship with carbon-nitrogen-phosphorus ratios in simulated constructed wetland system

2018 ◽  
Vol 78 (3) ◽  
pp. 545-555
Author(s):  
Xia Liu ◽  
Guohui Ning ◽  
Jianzhi Xie ◽  
Chunjing Liu ◽  
Ming Li
Keyword(s):  
Total Phosphorus ◽  
Rural Areas ◽  
Oxygen Demand ◽  
Volume Ratio ◽  
Ammonia Nitrogen ◽  
Domestic Sewage ◽  
Removal Rates ◽  
Pollutant Concentrations ◽  
Positive Correlations ◽  
C:P Ratios

Abstract For achieving the economical and efficient configuration of constructed wetlands (CWs), a simulated device of vertical flow CWs was used to investigate the effects of different volume ratios of substrates to two cold-resistant plants on pollutant concentrations as well as their ratios in effluent under different inflow domestic sewage concentrations. The average removal rates (ARRs) of ammonia nitrogen, total nitrogen (TN) and total phosphorus were 82.7%, 84.9% and 80.6% respectively in the treatments with zeolite but no plants, which increased by 22.6%, 20.8% and 14.9% compared with those without zeolite and plants. However, in the treatments with zeolite and planted grasses, the ARRs of the three pollutants were over 90%, and those of chemical oxygen demand were lower. The removal rates of ammonia nitrogen, TN and total phosphorus had negative correlations with C:N and N:P ratios and positive correlations with the C:P ratios. Increasing the ratio of zeolite to soil from 1:1 to 2:1 had no significant effects in the removal efficiency. It was suggested that planting Lolium perenne or Poa annua on the substrate with a zeolite to soil volume ratio of 1:1 could be considered as the optimum combination to purify the domestic sewage in north rural areas of China.

The performance of a two-stage SBR system in treating dye containing wastewater

2003 ◽  
Vol 47 (1) ◽  
pp. 291-296 ◽  
Author(s):  
X.-H. Wen ◽  
L.-Y. Fu ◽  
Y. Qian
Keyword(s):  
Pollutant Removal ◽  
Anaerobic Sludge ◽  
Scanning Microscope ◽  
Total Removal ◽  
Two Stage ◽  
Removal Rates ◽  
Operating Stability ◽  
Electron Scanning Microscope ◽  
The Stability

A two-stage SBR system treating the wastewater containing copper-phthalocyanin dye-Reactive Turquoise Blue KN-G (C. I. Reactive Blue 21, denoted by RTB) was investigated during a 200-cycle operation. The performance of the system, including pollutant removal rates, operating stability and sludge characteristics, may be a concern in the long-term run. The results shows that the system removed RTB efficiently despite the step-up RTB concentration from 13.1 to 107 mg/L in the influent. The average total removal rates of RTB were 81% to 92.5% due to the contribution of both anaerobic and aerobic stages, while stable effluent was produced with the help of the aerobic stage. The sludge in each reactor was in the steady state and of good activity on RTB removal. Moreover, the anaerobic sludge with the SVI value of 109.1 and the aerobic sludge with the SVI value of 103.2 had good settling properties, which was verified by hardly any presence of suspended solids in the effluent and an observation under an electron-scanning microscope. The adsorption and biodegradation were considered as the mechanism for the stability of the SBR system during the long-term run.

scholarly journals Synergistic Action of Plants and Microorganism in Integrated Floating Bed on Eutrophic Brackish Water Purification in Coastal Estuary Areas

2021 ◽  
Vol 8 ◽  
Author(s):  
Ming Liu ◽  
Youyuan Chen ◽  
Yadong Wu ◽  
Jiameng Guo ◽  
Ping Sun ◽  
...  
Keyword(s):  
Salt Tolerance ◽  
Water Purification ◽  
Brackish Water ◽  
Volcanic Rocks ◽  
Ammonia Nitrogen ◽  
Pollutant Removal ◽  
Water Bodies ◽  
Poor Growth ◽  
Coastal Estuary ◽  
Pollutants Removal

Eutrophic water bodies in coastal estuary areas usually show saline-alkaline characteristics influenced by tides. The purification performance of traditional planted floating beds in this water body is limited because of the poor growth of plants. A novel integrated floating bed with plants (Iris pseudoacorus), fillers (volcanic rocks and zeolites), and microbes named PFM was established, and the pollutant removal performance was studied. Results showed that the average ammonia nitrogen (NH4+-N), total nitrogen (TN), total phosphorus (TP), and permanganate index (CODMn) removal efficiencies of PFM were higher with the value of 81.9, 78.5, 53.7, and 72.4%, respectively, when compared with the other floating beds containing plants (P), fillers (F), microbes (M), and plants and fillers (PF) in this study. Therein, the most of NH4+-N (30.1%), TN (27.9%), TP (22.5%), and CODMn (43.6%) were removed by microbes, higher than those removed by plants and fillers. Analysis of the microbial community revealed that the establishment of PFM led to a higher microbial richness than M, and Acinetobacter, as the main microbes with the function of salt tolerance and denitrification, were dominated in PFM with a relative abundance of 6.8%. It was inferred that the plants and fillers might enrich more salt-tolerance microbes for pollutants removal, and microbes favored the growth of plants via degradation of macromolecular substrates. Synergistic actions in the process of eutrophic brackish water purification were established. This study provided an idea for the application of integrated floating bed in eutrophic and brackish water bodies purification in coastal estuary areas.

Sign in / Sign up

Export Citation Format

Share Document