FEM-Modelling of Open Stormwater Detention Ponds

Stormwater in urban areas is polluted with suspended materials which transport heavy metals and degrade the quality of the receiving waters. Since open detention ponds improve water quality, an investigation of a constructed pilot-scale detention pond was carried out. Measurements of inflow and outflow were performed and two flow-weighted samplers were used to collect representative samples of suspended solids and heavy metals. The particle size distribution was analysed to allow an estimation of the settling of suspended solids. Particle removal from a rain event was defined as two different phases where the first phase occurs during the rain event and the second phase after the event. In this paper only the first phase is considered. A FEM-software package (FIDAP) was used to calculate the three dimensional velocity flow field for one rain event. A sedimentation approach was applied to the flow field where paths were calculated through the detention pond for different particle sizes. The results from four different particle sizes show satisfactory agreement between FEM-calculated and observed particle removal. The results show that FIDAP is a useful tool to predict pollutant removal for open detention ponds with arbitrary geometry.

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Experimental investigation on water treatment by the combined nano MgO–nanofiltration technique

Water Science & Technology ◽

10.2166/wst.2011.510 ◽

2011 ◽

Vol 63 (11) ◽

pp. 2542-2546 ◽

Cited By ~ 5

Author(s):

Keqiang Zhang ◽

Yi An ◽

Feng Wang ◽

Lingling Lin ◽

Haigang Guo

Keyword(s):

Heavy Metals ◽

Experimental Investigation ◽

Water Treatment ◽

Suspended Solids ◽

Pollutant Removal ◽

Polluted Water ◽

Operating Pressure ◽

Nitrogen Species ◽

Combined System ◽

Mg Content

A combined system using nano MgO and nanofiltration (NF) membrane was established to purify polluted water in this experiment. The turbidity, permanganate index, UVA254, colony counts and the concentrations of NO3−, NO2−, NH4+, Fe, Mn and Mg of the effluents from each unit of this combined system were measured to investigate the pollutant removal of this system. Based on the results obtained, the combined nano MgO–NF system could efficiently remove many kinds of pollutants in this experiment, including organic matter, nitrogen species, heavy metals, suspended solids and bacteria. And the effluents could meet the standard of drinking water. Furthermore, increasing the nano MgO dosage could not elevate the removal ratio of the pollutants, but only increase the Mg content of the effluent. Thus, 0.05 g L−1 of nano MgO may be a suitable dosage for 2,000 L of polluted water treatment. Also, the operating pressure of NF membrane had no significant effect on pollutant removal when the operating pressure of NF membrane was increased from 0.3 to 0.9 MPa.

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Removal of pollutants by mycelium colonized sawdust

Water Practice & Technology ◽

10.2166/wpt.2021.028 ◽

2021 ◽

Author(s):

Osayomwanbo Osarenotor ◽

Helen M. K. Essandoh ◽

Isoken Tito Aighewic

Keyword(s):

Electrical Conductivity ◽

Particle Size ◽

Total Nitrogen ◽

Suspended Solids ◽

Oxygen Demand ◽

Total Dissolved Solids ◽

Biological Oxygen Demand ◽

Pollutant Removal ◽

Particle Sizes ◽

Removal Efficiencies

Abstract Slaughterhouses generate wastewater daily and often discharge it to the environment. Many lack wastewater treatment systems, due to such systems' typically high cost and technological demands. In this study slaughterhouse wastewater was filtered through columns of mycelium – Pleurotus ostreatus – grown on sawdust substrates of different particle sizes. The columns' pollutant removal efficiencies were evaluated for color, turbidity, total suspended solids, total dissolved solids, electrical conductivity, dissolved oxygen, biological oxygen demand (BOD), chemical oxygen demand, total nitrogen and total phosphorus. The best color (75%), BOD (88%) and total nitrogen (86%) removal efficiencies were recorded with 2.36 mm particle size and 9 cm depth. Electrical conductivity removal efficiency was best with 2.36 mm particle size but 3 cm bed depth. The study showed that particle size has a significant effect on physiochemical pollutant removal by mycelium-colonized sawdust systems.

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Pollutant Removal from Highway Runoff Using Retention/Detention Units

Acta Polytechnica ◽

10.14311/220 ◽

2001 ◽

Vol 41 (2) ◽

Author(s):

Ashraf El-Shahat Elsayed ◽

A. Grünwald ◽

D. Dvořák

Keyword(s):

Czech Republic ◽

Suspended Solids ◽

Peak Flow ◽

Total Suspended Solids ◽

Pollutant Removal ◽

Highway Runoff ◽

Detention Ponds ◽

Site Characteristics ◽

Strong Relation ◽

Runoff Quality

Highway runoff contains total suspended solids, hydrocarbons, oil and greases, chloride, and other contaminants that are transported in solution and particulate forms to adjacent floodplains, roadside swales, and retention/detention ponds. Oil and grit chambers represent a type of retention/detention unit used for removing heavy particulates and adsorbed hydrocarbon particulates. Storage/sediment units also represent a type of retention/detention unit used for controlling peak flow and removing suspended solids. The aim of this study is to evaluate the effect of traffic volume and site characteristics on highway runoff quality. The study also aims to evaluate the performance of retention/detention units that collect runoff from the Prague-Brno and Prague-Plzeň highways, Czech Republic. The results of this study indicate no definitive relationship between average daily traffic and concentration of runoff constituents, though the site characteristics have a strong relation to some constituents. The results also show that retention/detention units are effective in treating organic compounds.

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Pollutant removal efficiency of a retrofitted stormwater detention pond

Water Quality Research Journal ◽

10.2166/wqrjc.2013.020 ◽

2013 ◽

Vol 49 (2) ◽

pp. 124-134 ◽

Cited By ~ 20

Author(s):

Jason Faber Carpenter ◽

Bertrand Vallet ◽

Geneviève Pelletier ◽

Paul Lessard ◽

Peter A. Vanrolleghem

Keyword(s):

Removal Efficiency ◽

Retention Time ◽

Suspended Solids ◽

Total Suspended Solids ◽

Pollutant Removal ◽

Sluice Gate ◽

Pollutant Concentrations ◽

Detention Pond ◽

Stormwater Retention ◽

Pollutant Removal Efficiency

The objectives of this study were to characterize the stormwater runoff for a residential catchment, evaluate the present detention pond removal efficiency for different pollutants, and evaluate how its efficiency can be increased by controlling the pond stormwater retention time. The analysed pollutants were total suspended solids (TSS), total metals and ammonia. Runoff pollutant concentrations were generally found to agree with literature for the small residential catchment. The design of the original pond was such that low retention times of most analysed pollutants occurred, causing a lower than expected removal efficiency when compared to similar types of ponds. The retrofitting of the pond consisted of adding a sluice gate at the outlet in order to retain stormwater for longer periods of time. The retrofit allowed drastic improvement of the removal efficiency for TSS, NH3-N and zinc, from 39 to 90%, 10 to 84%, and 20 to 42%, respectively.

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Field-Scale Studies of Subsurface Flow Constructed Wetlands for Stormwater Quality Enhancement

Water Quality Research Journal ◽

10.2166/wqrj.1997.008 ◽

1997 ◽

Vol 32 (1) ◽

pp. 101-118 ◽

Cited By ~ 6

Author(s):

Q.J. ROCHFORT ◽

W.E. Watt ◽

J. Marsalek ◽

B.C. Anderson ◽

A.A. Crowder

Keyword(s):

Organic Carbon ◽

Constructed Wetlands ◽

Suspended Solids ◽

Nutrient Loading ◽

Subsurface Flow ◽

Reaction Rates ◽

Pollutant Removal ◽

Order Kinetic ◽

Dissolved Metals ◽

Subsurface Flow Constructed Wetlands

Abstract Two subsurface flow constructed wetlands were tested for pollutant removal performance in conjunction with an on-line stormwater detention pond, in Kingston Township, Ontario. The 4.9 m2 wetland cells were filled with 9 mm limestone gravel, and planted with cattail, common reed and spike rush. Changes in nutrient (total organic carbon, PO43- and NH4+), suspended solids and metal (Cu, Pb, Zn) concentrations were used to assess performance. Contaminant removal occurred through a combination of physical, chemical and biological means. As with any biological system, variation in performance of stormwater wetlands can be expected to occur as a result of fluctuations in contaminant loading, contact time and ambient environmental conditions. Storm pond effluent was delivered in continuous flow through the wetlands (during baseflow and event conditions), with a detention time of 1 to 3 days. The wetlands were able to maintain removal rates of up to 39% for orthophosphate even during the more severe conditions of fall dieback. Average removal of suspended solids (46%) and dissolved metals (Cu 50%) remained similar throughout all tests. Organic carbon was reduced by less than 10% during these tests. Low nutrient levels in the pond effluent were supplemented by spiking with sources of carbon, nitrogen and phosphorus during pulsed loading conditions. Daily sampling produced a time series, which illustrated the rates of decline in concentration of nutrients. First order kinetic assimilation rates ranged from 1.7 d-1 for NH4002B to 0.12 d-1 for organic carbon, which were noticeably lower when compared with municipal and industrial wastewater treatment rates. Three methods of sizing stormwater wetlands (impervious surface area, volumetric load and kinetic reaction rates) were compared using the same design storm and data from this study. From this comparison it was seen that the kinetic sizing approach proved to be the most versatile, and allowed for adaptation to northern climatic conditions and anticipated nutrient loading.

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Performance and Modelling of a Highway Wet Detention Pond Designed for Cold Climate

Water Quality Research Journal ◽

10.2166/wqrj.2009.027 ◽

2009 ◽

Vol 44 (3) ◽

pp. 253-262 ◽

Cited By ~ 7

Author(s):

Jes Vollertsen ◽

Svein Ole Åstebøl ◽

Jan Emil Coward ◽

Tor Fageraas ◽

Asbjørn Haaning Nielsen ◽

...

Keyword(s):

Rate Constants ◽

Pond Water ◽

Pollutant Removal ◽

Cold Climate ◽

Traffic Load ◽

Substantial Part ◽

First Order ◽

Detention Pond ◽

Time Of Year ◽

Wet Detention Pond

Abstract A wet detention pond in Norway has been monitored for 12 months. The pond receives runoff from a highway with a traffic load of 42,000 average daily traffic. Hydraulic conditions in terms of inflow, outflow, and pond water level were recorded every minute. Water quality was monitored by volume proportional inlet and outlet samples. During most of the year, excellent pollutant removal was achieved; however, during two snowmelt events the pollutant removal was poor or even negative. The two snowmelt events accounted for one third of the annual water load and for a substantial part of the annual pollutant discharge. The performance of the pond was analyzed using a dynamic model and pollutant removal was simulated by first-order kinetics. Good agreement between measurement and simulation could be achieved only when choosing different first-order rate constants for different parts of the year. However, no relation between the rate constants obtained and the time of year could be identified, and neither did the rate constants for different pollutants correlate. The study indicates that even detailed measurements of pollutant input and output allow only average performance to be simulated and are insufficient for simulating event-based variability in pond performance.

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Biolixiviation des métaux lourds et stabilisation des boues d'épuration : essai en bioréacteur opéré en mode cuvée

Canadian Journal of Civil Engineering ◽

10.1139/l93-006 ◽

1993 ◽

Vol 20 (1) ◽

pp. 57-64 ◽

Cited By ~ 12

Author(s):

R. D. Tyagi ◽

J. F. Blais ◽

N. Meunier ◽

D. Kluepfel

Keyword(s):

Heavy Metals ◽

Sewage Sludge ◽

Suspended Solids ◽

Elemental Sulfur ◽

Batch Reactor ◽

Fecal Coliforms ◽

Sludge Stabilization ◽

Sludge Digestion ◽

Batch Time ◽

Phosphorus And Potassium

A biological process of heavy metals solubilization and sewage sludge stabilization was studied in a batch reactor of 30-L capacity. The acclimatized leaching microflora was composed of two major groups of thiobacilli: less acidophilic and acidophilic. A batch time of 10 days allows a substantial metal solubilization: cadmium (100%), copper (80%), manganese (80%), nickel (46%), and zinc (100%). The bioleaching process also causes a significative decrease in sludge total suspended solids (25%) and volatile suspended solids (32%), and a considerable reduction (under the detection limit of 10 cfu∙mL−1) of indicator bacteria (total coliforms, fecal coliforms, fecal streptococci). After filtration or centrifugation of the leached sludge, the solubilized metals were precipitated by lime neutralization. The phosphorus and potassium sludge contents were not affected by bioleaching process. These results indicate that the process of sludge digestion and metal leaching can be conducted in parallel in the same reactor. Key words: sewage sludge, heavy metals, bioleaching, stabilization, thiobacilli, elemental sulfur.

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Dynamic behavior of suspended pollutants and particle size distribution in highway runoff

Water Science & Technology ◽

10.2166/wst.2002.0771 ◽

2002 ◽

Vol 46 (11-12) ◽

pp. 413-418 ◽

Cited By ~ 104

Author(s):

H. Furumai ◽

H. Balmer ◽

M. Boller

Keyword(s):

Heavy Metals ◽

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Suspended Solids ◽

Dynamic Change ◽

First Flush ◽

Highway Runoff ◽

Runoff Rate ◽

Highway Drainage

Continuous runoff quality monitoring was conducted for one month at urban highway drainage with an area of 8.4 ha. Dynamic change of suspended solids and heavy metal concentrations were investigated during first flush periods, taking the particle size distribution into consideration. Except for Pb, the concentrations of TSS and heavy metals in runoff were within the range of the EMC reported in recent highway runoff research. Particle-bound heavy metals (Zn, Pb, and Cu) accounted for more significant pollutant loads than soluble fractions. Their content decreased with increasing total SS concentration in runoff samples. The results of particle size distribution (PSD) analysis of runoff samples indicate that high TSS concentration samples contained coarser particles. Based on the PSD results, a stepwise wash-off phenomenon of TSS under varying runoff rate conditions was explained by the different washoff behavior of fine (< 20 mm) and coarser particles.

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Microbial Flocculants as an Alternative to Synthetic Polymers for Wastewater Treatment: A Review

Symmetry ◽

10.3390/sym10110556 ◽

2018 ◽

Vol 10 (11) ◽

pp. 556 ◽

Cited By ~ 20

Author(s):

Faouzi Ben Rebah ◽

Wissem Mnif ◽

Saifeldin M. Siddeeg

Keyword(s):

Heavy Metals ◽

Wastewater Treatment ◽

Suspended Solids ◽

Specific Resistance ◽

Oxygen Demand ◽

Synthetic Polymers ◽

Operating Parameters ◽

Flocculating Activity ◽

Microbial Strains ◽

Active Substances

Microorganisms such as bacteria, fungi, and microalgae have been used to produce bioflocculants with various structures. These polymers are active substances that are biodegradable, environmentally harmless, and have flocculation characteristics. Most of the developed microbial bioflocculants displayed significant flocculating activity (FA > 70–90%) depending on the strain used and on the operating parameters. These biopolymers have been investigated and successfully used for wastewater depollution in the laboratory. In various cases, selected efficient microbial flocculants could reduce significantly suspended solids (SS), turbidity, chemical oxygen demand (COD), total nitrogen (Nt), dye, and heavy metals, with removal percentages exceeding 90% depending on the bioflocculating materials and on the wastewater characteristics. Moreover, bioflocculants showed acceptable results for sludge conditioning (accepted levels of dry solids, specific resistance to filtration, moisture, etc.) compared to chemicals. This paper explores various bioflocculants produced by numerous microbial strains. Their production procedures and flocculating performance will be included. Furthermore, their efficiency in the depollution of wastewater will be discussed.

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PEMANFAATAN KITOSAN DARI LIMBAH CANGKANG BEKICOT (Achatina fulica) SEBAGAI ADSORBEN LOGAM BERAT SENG (Zn)

Konversi ◽

10.20527/k.v5i1.4775 ◽

2018 ◽

Vol 5 (1) ◽

pp. 22

Author(s):

Stevano Victor M. ◽

Bayu Andhika ◽

Isna Syauqiah

Keyword(s):

Heavy Metals ◽

Atomic Absorption ◽

Water Samples ◽

Size Variation ◽

Second Phase ◽

Achatina Fulica ◽

Snail Shell ◽

Production Stage ◽

Two Phases ◽

Chitosan Powder

Abstrak- Telah dilakukan pemanfaatan cangkang bekicot (Achatina fulica) sebagai adsorben logam berat seng (Zn). Penelitian ini bertujuan untuk mengetahui jumlah kitosan yang didapat dari cangkang bekicot, dan mengetahui kemampuan adsorben kitosan dalam uji adsorpsi yang menggunakan sampel air yang tercemar seng (Zn). Pembuatan kitosan dari cangkang bekicot dilakukan dengan dua tahap yaitu tahap pembuatan kitosan dengan variasi ukuran kitosan 250 micron dan 355 micron. Tahap pembuatan kitosan terdiri dari pembuatan serbuk cangkang bekicot, deproteinasi, demineralisasi, depigmentasi dan deasetilasi. Tahap ke dua yaitu uji penyerapan kitosan terhadap logam berat seng (Zn) dengan variasi jumlah massa kitosan yang digunakan yaitu: 1 gram, 3 gram, 6 gram dan 9 gram. Sampel tersebut diuji dengan menggunakan Atomic Absorption Spectrophotometric (AAS) untuk mengetahui konsentrasi logam berat seng (Zn) yang terkandung di dalamnya. Hasil penelitian menunjukan bahwa kitosan yang didapat dari cangkang bekicot untuk ukuran 250 micron yang sebesar 95,27%, dan untuk ukuran 355 micron yaitu sebesar 96,18%. Daya serap optimum kitosan didapat pada kitosan berukuran 250 micron dengan massa kitosan 9 gram. Kata kunci: Adsorbsi, mikron, cangkang bekicot dan logam berat seng (Zn) Abstract- The used of snail shell (Achatina fulica) as adsorbent of heavy metals zinc (Zn). This study aims to determine the amount of chitosan derived from snail shells, and knowing the ability of chitosan adsorbent in adsorption tests using water samples were contaminated zinc (Zn). Preparation of chitosan from the shells of snails be done in two phases: the manufacture of chitosan with chitosan size variation of 250 micron and 355 micron. Production stage consists of the manufacture of chitosan powder snail shells, deproteinization, demineralization, depigmentasi and deacetylation. The second phase of the test chitosan absorption of heavy metals zinc (Zn) with a variation of the mass amount of chitosan that is used as follows: 1 gram, 3 grams, 6 grams and 9 grams. The sample is tested by using Atomic Absorption Spectrophotometric (AAS) to determine the concentration of heavy metals zinc (Zn) contained in it. The result showed that chitosan is obtained from the snail shell to the size of 250 microns, which equal to 95.27%, and for the size of 355 microns that is equal to 96.18%. Optimum absorption of chitosan obtained at chitosan measure 250 microns with a mass of 9 grams of chitosan. Keywords: Adsorption, micron, snail shells and heavy metals zinc (Zn).

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