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Treatment conditions for the removal of contaminants from road runoffHallberg, Magnus January 2007 (has links)
The pollutant load in road runoff is related to traffic densities and road maintenance activities. Inurbanised areas treatment of road runoff is common and often considered necessary. The pollutantsare partitioned between the particulate and dissolved matter. However, the contaminantstend to have an affinity to the particulate material. Sedimentation, the predominant treatmentmethod for road runoff uses various types of ponds. Design tools used for stormwater treatmentsystems are based on extensive data from existing treatment systems. The variations in the empiricaldata make it difficult when attempting to evaluate precise conditions for pollutant removaland thereby minimising the land use for a treatment facility. This is a concern in highly urbanisedareas where land use often is restricted.In this work, field studies were conducted in three separate watersheds along the same motorwaywith an annual average daily traffic exceeding 120,000 vehicles. The aim was to assess treatmentconditions for the removal of contaminants from road runoff.The study of mass transport of total suspended solids used the EU Directive (1991/271/EEC)discharge requirement for urban wastewater treatment: 60 mg/l during winter and summer. Theresults showed that a capture of the total runoff volume was necessary during both seasons. Tenmetals (Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn), as dissolved and particulate bound, werestudied in the road runoff during a winter season and the following summer period. The dissolvedpart of Al, Cd, Co, Cr, Mn, and Ni was significantly higher in winter. The mass concentration(mg/kg) for all metals was significantly higher over the summer except for Al and Co, whichshowed a higher mass concentration during the winter. The total metal concentration showed agood correlation to total suspended solids (TSS) during winter with exception for Cd. Good correlationto TSS was also found for the summer period for Al, Cu, Fe, Mn, Ni, and Zn. A simplemodel could describe sedimentation by the initial concentration of TSS, albeit road salt (NaCl)had a significant impact on the sedimentation process during winter. Removal of dissolved metalswas studied by column experiments using water granulated blast furnace slag. The result showedgood removal for Cd, Cu, Ni, and Zn independent of NaCl concentrations. Sediment accumulation(mg sediment/mm precipitation) was relatively consistent for the studied summer seasons asopposed to winter. The sediment differed in metal mass concentrations (mg/kg) between theseasons. Concentrations of Cu and Zn were high in regard to the guidelines for sensitivity ofsediment dwelling organisms and Swedish guidelines for contaminated soils.The findings suggest that the entire runoff volume must be captured for treatment. The reductionof TSS concentration could be estimated for a specific surface load (m/h). This would alsoapply for majority of the studied metals that correlated well to the particulate material. Reactivefilter technology using water granulated blast furnace slag could be applied for treatment of runofffor the reduction of dissolved metals. However, long-term studies are necessary for its practicalimplementation. Furthermore; the work shows that on-line turbidity measurements could beused for expedient process control for treatment facilities in similar watersheds dominated byroads. The work could be used together with existing design methods and models to evaluate andoptimise road runoff treatment. / Föroreningsbelastningen i vägdagvatten är beroende av trafikbelastningen och vägunderhållet. Iurbaniserade områden är behandling av dagvatten vanlig och ofta bedömd nödvändig. Föroreningarnaär lösta och partikulära, men har vanligen en affinitet till det partikulära materialet. Denförhärskande behandlingsmetoden för dagvatten är sedimentering, vanligen i dammar. Designmodellernabygger på data från olika befintliga dagvattenanläggningar. Det varierande ursprungettill det empiriska underlaget medför svårighet att precist värdera designförutsättningarna och såledesminimera behandlingsanläggningens storlek. I förtätad stadsmiljö, där tillgång på mark ärbegränsad, kan detta vara ett problem.I detta arbete har fältförsök genomförts i tre avrinningsområden vilka domineras av en motorledmed en årlig dygnstrafik större än 120,000 fordon för att utvärdera behandlingsförutsättningar förvägdagvatten.Masstransporten av suspenderat material (SS) utvärderades utifrån EU Direktivet(1991/271/EEC) och gränsvärdet för avloppsvatten på 60 mg/l under vinter och sommar. Studienvisade att hela avrinningsvolymen bör behandlas oberoende av säsong. Fördelningen mellanpartikulärt och löst material studerades för tio metaller (Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn)under vinter och sommar. Den lösta delen av Al, Cd, Co, Cr, Mn och Ni var signifikant högreunder vintern. Den partikulära koncentrationen (mg/kg) för samtliga metaller var högre undersommaren med undantag för Al och Co vilka förekom i högre halter under vintern. Totalhalten(μg/l) av metallerna korrelerade väl med SS under vintern med undantag för Cd. Likaledes uppvisaderesultaten en god korrelation mellan SS och Al, Cu, Fe, Mn, Ni och Zn under sommaren.Sedimenteringsegenskaperna kunde beskrivas med en enkel modell utifrån koncentration av SS,men förhöjda halter av vägsalt (NaCl) befanns påverka sedimenteringen under vintern. Reduktionav lösta metaller studerades i pilotförsök med vattenkyld granulerad masugnsslagg. God avskiljningerhölls för Cd, Cu, Ni och Zn oberoende av förhöjda halter av vägsalt. Ackumulering avsediment (mg sediment/mm nederbörd) befanns vara konstant under sommaren i motsats tillstuderade vinterperioder. Sedimentkoncentrationerna av Cu och Zn var förhöjda med avseendepå riktlinjer för känslighet hos sedimentlevande organismer samt för återanvändning av slam.Resultaten visar att hela avrinningsvolymen måste behandlas. Reduktion av SS samt huvuddelenav metallerna, vilka visade god korrelation till det partikulära materialet, kan skattas utifrån enspecifik ytbelastning (m/h). Reduktion av lösta metaller kan ske med granulerad masugnsslagg,dock bör långtidsstudier genomföras. Vidare visar studien på möjligheten att nyttja kontinuerligturbiditetsmätning för en effektiv och praktisk processkontroll i reningsanläggningar för liknandeavrinningsområden med hög trafikbelastning. Resultaten av arbetet kan användas för bedömningoch optimering av vägdagvattenbehandling tillsammans med existerande designmetoder och modeller. / QC 20100709
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Effect of resuspension on mineralisation of organic material : Laboratory studies of water movement intensity and concentration of suspended sedimentStenborg Larsson, Charlotte January 2005 (has links)
The Earth’s surface contains of 71% oceans and a large part of the global carbon cycle takes place in the oceans. In the aquatic environment, the sediment-water interface plays an important role for the mineralisation of organic material. One factor that can affect the mineralisation is resuspension. Resuspension cause mixing of surface sediments and bottom water and result in a redistribution of the sediment when it settles again. Resuspension also increases the transport of oxygen into the sediment, reduces the diffusive boundary layer surrounding particles, and enhance the nutrient uptake. Resuspension can be induced by both wave action and bottom currents and is a common physical process in both shallow coastal areas and in the deep ocean. Human impacts, such as dredging and trawling, can also cause resuspension. The effect of resuspension on mineralisation of organic material was studied in two experiments ex situ during December to April 2004/2005. The aim for Experiment 1 was to investigate how the intensity of the resuspension event affects the degradation rate. The aim for Experiment 2 was to investigate how different concentrations of resuspended sediment affect the degradation rate of organic matter. Sediment samples were collected in December and late March at a marine field station, Askö, Sweden. Sediment and bottom water were transferred to and incubated in sealed bottles. For Experiment 1, resuspension was created in bottles with a specially designed rotary table, creating different intensity of water movements. In Experiment 2, bottles with different concentrations of sediment were put on an ordinary rotary table. The mineralisation rates were in both experiments monitored by daily sampling of sediment-water slurry, and analysed for total inorganic carbon by a gas chromatography with a thermal detector, GC-TCD. Results from Experiment 1 did not show any clear patterns regarding inorganic carbon formation. Experiment 2 did show clear patterns for two of six replicates of mineralisation of organic material. For these replicates the mineralisation rate were low according to previous studies. However, the sediment concentration seems to not affect the mineralisation rate. For both experiments, valuable information on how to better design experiments to investigate the importance of resuspension and the effect of mineralisation of organic material was yielded. Hence, further studies are needed to continue the investigation of the importance of resuspension for the mineralisation rate of organic material, and its impacts on the nutrient fluxes in the oceans.
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To Analyze The Relationship between BOD, Nitrogen And Phosphorus Contents at Constant Dissolved Oxygen Concentration In Municipal Wastewater TreatmentZaidi, Syed Faraz Ali, Sudthanom, Juthatip January 2011 (has links)
In this report, the application of Principle Component Analysis (PCA) and Partial Least Square (PLS) regression analyzing methods used to understand the relationship of interdependent loads in municipal wastewater treatment plant. Two different wastewater treatment plants were chosen for analysis of the relationship between interdependent loads. Firstly, the collected data of incoming wastewater and outgoing water from both Västerås and Eskilstuna wastewater treatment plants were analyzed to find some relationship or correlation between contents and compare the data of both the plants. Secondly, the correlated contents were used to generate the regression model for predicting the value in the future, in this report we have focussed only on ammonium nitrogen value for regression model. The PCA study shows the variation between incoming and outgoing wastewater’s characteristics given by Västerås and Eskilstuna plant. / BOD, ammonium nitrogen, nitrogen, phosphorus
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Analyse der Erosionsdynamik im Einzugsgebiet des Landwassers (Oberlausitz) – Einfluss auf Gewässergüte und MakrozoobenthosdriftKändler, Matthias 12 October 2012 (has links) (PDF)
In der vorliegenden Arbeit werden für ein stark anthropogen beeinflusstes Einzugsgebiet die komplexen Zusammenhänge zwischen Witterung, Landnutzung, Erosion, Gerinneabfluss, Stofffrachten und Makrozoobenthos analysiert. Dafür wurde eine Messstation eingerichtet, an der Fließgeschwindigkeit, Trübung, pH Wert und Leitfähigkeit kontinuierlich gemessen wurden. Mit Hilfe eines durchflussgesteuerten Probennehmers wurden Wasserproben entnommen und im Labor auf verschiedene Inhaltsstoffe (Nährstoffe, Schwermetalle) analysiert sowie die Konzentration von Feinsediment bestimmt. Es konnte eine Beziehung zwischen Trübung und Sedimentkonzentration abgeleitet werden.
Die chemischen Analysen zeigten einen komplexen Zusammenhang zwischen der Erosion von landwirtschaftlichen Flächen, dem Stoffeintrag von versiegelten Arealen (Verkehrsflächen, Dächer) aber auch witterungs- und vegetationsbedingte saisonale Effekte. Ein Vergleich der Eigenschaften der Schwebstoffe/Feinsediment im Landwasser mit denen von Ackerboden (Maisfelder) zeigte, dass diese die „chemische Handschrift“ der Ackerböden trugen.
Mit Hilfe der Modelle EROSION 3D und ICECREAM wurden die abgetragenen Bodenmengen für das Einzugsgebiet bzw. für ausgewählte Hänge quantifiziert. EROSION 3D überschätzt den Bodenaustrag aus dem Untersuchungsgebiet deutlich. Das Modell ist ungeeignet, um für das Einzugsgebiet reale Abtragswerte mit den zur Verfügung stehenden flächenhaften Eingangsdaten zu berechnen. Bereits für Einzelhänge werden zu große Bodenabträge berechnet. Verstärkend kommt hinzu, dass auf Grund der Modellannahme jeder Partikel, der das Gewässer erreicht auch aus dem Einzugsgebiet heraustransportiert wird. Das Modell kann empfohlen werden, um erosionsgefährdete Flächen auszuweisen.
In der Untersuchungsperiode von 2009 bis Juli 2011 wurde an Hand von 57 Driftfängen mit unterschiedlichen hydrologischen Randbedingungen die Wirkung der Fließgeschwindigkeit auf den Übergang benthischer Invertebraten in die freie Welle identifiziert. Aus Uferbereichen gelangen zufällig terrestrische Invertebraten in das Gewässer, deren Anteil sich durch gewässernahen Oberflächenabfluss in Folge von Niederschlagsereignissen erhöht. Die Driftdichte nimmt ab Fließgeschwindigkeiten von 0,3 m/s deutlich zu. Oligochaeta, Cyclopoida und Dipolstraca driften verstärkt bei Fließgeschwindigkeiten >0,6 m/s.
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Using multi-frequency acoustic instruments to investigate the suspended sediment grain size and concentration characteristic in flume experiment and in the fieldWu, Chen-I 26 July 2012 (has links)
In the past, the suspended sediment concentration (SSC) was mainly measured by the optical backscattering device (OBS) and water sample filtration. However, there has been a new development that user is based on the acoustics backscattering (ABS) to measure the SSC in the world. The acoustic instruments have some advantages that the optical ones do not have. For example, acoustic instruments are not effected by high turbidity, biofouling and high viscosity in the water. Acoustic instruments have high spatial and temporal resolutions. And they can immediately indicate the SSC changes than the water sample filtration method. Therefore, in this study we used the multi-frequency acoustics instrument (AQUAscat-1000) to investigate the relations of the suspended sediment size and concentration to the acoustic characteristics.
The results are separated into two parts: (1) The calibration process in the flume. (2) The acoustic results in the field experiment. In the first part, we examined the range of preferred bin size with respect to the different frequencies as well as the condition in the flume, and determine that conclude the 20 mm is the best range for our case. In addition, the gain should be used when the maximum SSC is less than 100 mg/l and vice versa. Therefore, in the field case around the river mouth, the signal gain should be turned off due to high concentrations. According to the sensitivity of the backscatter intensity of different frequencies to the suspended particle sizes, multiple frequencies are needed to derive the SSC when the sediment size becomes smaller. The last point in this part is the comparison of the results between the acoustics and optical instruments. When the suspended particles in the water column are transparent, the optical measurement of the SSC is underestimated, but the acoustic method is not.
The result of the field experiment in 2009 showed that the AQUAscat-1000 is a better instrument to quantify SSC than the optical instruments. The SSC increase caused by the bottom sediment re-suspension was due to the wave shear. In the 2011 experiment, although the acoustic results overestimated the SSC at some points but they still had higher relation and significance with water sample data than the optical measurements. The SSC increase caused by the bottom sediment re-suspension was due to the current shear.
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Research of the R.P.T.I. International L.T.D. the suspended punishment to close down Porter diamond modelLiu, Yung-Chieh 14 August 2012 (has links)
Construction ¡§traffic control system of high-speed road network Northern traffic information management and coordination command center systems engineering" Vendor, RPTI, due to execute his right to stop, causing to others under construction engineering progress into delay or even halt, Furthermore, causing irreparable damage to the public interest. This action will also affect either the progress to be procrastinating, or failure of the entire project of construction plan. In a word, it stalls off the development of the ITS industrial. This paper aimed at studying the case manufacturers suffer administrative relief and derivative right to stop financial crises, and finally to the brink of bankruptcy.
Stopped right disputing caused by uncertain legal concept of cognitive difference. Once the vendor has been suspended for the execution of the contract likely to have non-compliance or abuse of the fact that compliance; legal system face the compliance phase of the case as a stop right to the subject, but also derivative is easy to mediation and complaint competing, as well as administrative litigation court rejected status; complaint Review lengthy process to consider the judgment as if the provisions of the appeal decision has resulted in the responsible entity procurement operations distress. The vendor will be published in the Government Procurement Gazette by the responsible organization. As the result, it might be more difficulty to maintain the business; moreover, the published not only announce to loss of right of government bidding; even worse, will affect the company¡¦s Goodwill and survival of business. The Suspended punishment of the Government Procurement Law system, whether is appropriateness, and the further influencing factors of overall competitiveness.
Made by MICHAEL PORTER¡¦s diamond theory, "stop right" under the "other external factors opportunities (opportunity and Government policy) "An analysis of the State ITS industrial competitiveness. Diamond combination of the four factors is well and available, but opportunities exist does not necessarily help to enhance the competitiveness of industry, but counterproductive injury, will allow businesses or companies collapse, or even disappear.
As the ITS industry as the government established policy of the Department of National Infrastructure, the opportunity this factor evolved out of the results of the company, the enterprise, the whole industry chain and even the country's competitiveness will be immeasurable. Therefore, this article will discuss actual cases of the case manufacturer¡¦s discussion.
RPTI is to the brink of bankruptcy, forced to dissolve, engineers, technicians. Subsequently, a large number of employees left, the company¡¦s core values (the process of information technology and intelligent transportation systems technology and system integration capabilities) gone, the competitiveness of the domestic intelligent transportation industry will thus setback
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The seasonal trend and characteristics of heavy metals in atmospheric particulates in Nantzu Export Processing ZoneChang, Hung-Tse 15 August 2012 (has links)
To characterize the size distributions, concentrations and sources of heavy metal associated with suspended particles, a total of 12 months of sampling periods were taken by Micro-Orifice Uniform Deposit Impactor (MOUDI) in the Nantzu Export Processing Zone from January to December 2011,
The concentrations of suspended particles ranged from 54.7 to 203 £gg/m3. Both autumn and winter had significantly higher levels of suspended particles than in spring and summer. The mass concentrations of fine particles accounted for ~50% of the mass concentrations of suspended particles. The mass concentrations of PM2.5 accounted for 50.2-70% of the mass concentrations of PM10. The mass concentrations of PM1 accounted for 24-38.3% of the mass concentrations of PM10. These results indicated that fine particles dominated in atmospheric particulates in Nanzih Export Processing Zone. In addition, among the PM10, PM2.5 and PM1, significant correlations were found.
The crustal elements (Al, Fe, Ca, Mg, K and Na) and sulfate are dominant during the sampling periods, which accounting for ~95% of the total concentrations. The crustal elements were observed mainly in coarse particles, while sulfate was found mainly in fine particles. The concentrations of all crustal elements decreased in summer could be attributed to the meteorological conditions and chemical mechanism. By using the enrichment factor (EF) to distinguish the sources of heavy metals in PM10, PM2.5 and the results showed that EF values of crustal elements in PM10 ranged from 1 to 10, suggesting PM10 might come from the resuspension of soil and road dust. In addition, Pb, Zn, As, Se, Mo, Sb and sulfate were observed at higher EF values in both PM2.5 and PM1, indicating the influence of anthropogenic emissions in fine particles.
The results from Pearson¡¦s correlations indicated that PM10 in the Nantzu Processing Zone were mainly from the resuspension of soil and road dust, while fine particles (PM2.5 and PM1) may be from the traffic emissions and petrochemical industry in Nanzih and Renwu.
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Physicochemical Characteristics and Source Apportionment of Ambient Suspended Particles at Boundary and Sensitive Sites Surrounding a Steel Manufacturing PlantLiao, Chia-cheng 24 August 2012 (has links)
Steel industry is a highly polluted industry and one of the most important stationary sources in Kaohsiung City. The steel manufacturing process could emit a huge amount of particles, such as the sintering process, the blast furnace operation, and the raw material handling process. Suspended particles emitted from steel industry could deteriorate ambient air quality and cause adverse effects on human health.
In order to understand the impact of steel industry on ambient air quality in Siaogang District and to identify potential pollution sources, this study selected a integrated steel manufacturing plant located at Siaogang District to conduct a sampling protocol of suspended particulate matter (PM) at ambient sites (A1~A5) and sensitive sites (S1~S5) from July 2011 to March 2012. The size distribution of suspended particles in four seasons was measured with PM10 high-volume samplers, dichotomous samplers, and MOUDI for 3 days (24 hours for single sampling), and dustfall samplers for one month, to investigate the spatial distribution and temporal variation of PM concentration. After sampling, the physicochemical properties of PM, including mass concentration, particle size distribution, dustfall concentration, water-soluble ionic species, metallic elements, and carbonaceous contents, were further analyzed.
Field measurement of ambient PM showed that the averaged ambient PM10 concentration (53.54 - 203.56 £gg/m3) were higher than sensitive sites (55.06 - 140.07 £gg/m3) and the averaged ambient PM2.5 concentration of ambient (23.10 - 120.21£gg/m3) were higher than sensitive sites (12.52 - 65.62 £gg/m3). No matter ambient or sensitive sites, it showed a tendency of lower concentration in summer, indicating that concentration variation of PM10 and PM2.5 were highly affected by meteorological factors (such as wind direction, wind speed, and relative humidity) in Siaogang District. Furthermore, a t-test result showed that ambient and sensitive sites have similar pollution sources since the p-values were in significantly different.
Chemical analysis of PM results showed that the most abundant water-soluble ionic species of PM at the ambient and sensitive sites were secondary inorganic aerosols (SO42-, NO3-, and NH4+) and [NO3-]/[SO42-] showed that ionic species were mainly emitted from stationary sources. Fe, Al, K and Ca were the major metallic elements of this study, and the major pollution sources contain industries, traffics, and road dusts. Additionally, the raw material handling process was the major pollution source of PM. Correlation analysis of OC and EC showed that PM at ambient and sensitive sites were originated from primary sources, such as vehicles, industries, road dusts, and human activities.
Results obtained from PCA and CMB receptor modeling showed that both PM2.5 and PM10 highly correlated with wind direction in different season and the major pollution sources were industry pollution (including petroleum refineries, power plants, waste incinerators, consistent operating steel mills and electric arc furnace steel mills, etc.), followed by local traffics and derivative. Furthermore, marine aerosols were one of the important pollution sources at sensitive sites (S1, S4, and S5) where close to the ocean.
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Evaluation of compost specifications for stormwater managementBirt, Lindsay Nicole 15 May 2009 (has links)
Urban development will continue to increase in Texas because of population growth and urban sprawl. Despite the desire for urbanization and expansion of the economy, this growth increases the amount of construction, which, if not properly managed, can increase non-point source pollution and threaten surface water quality. Therefore, Texas Department of Transportation (TxDOT) has approved and promoted the use of compost as a stormwater best management practice (BMP) during highway construction. The objectives of this study were to construct and calibrate an indoor rainfall simulator and to determine the effectiveness of using compost rather than conventional hydroseeding or topsoil to reduce erosion from disturbed soils. Runoff rates, interrill erosion, and interrill erodibility were determined and compared across five compost treatments following TxDOT specifications for compost applied as an erosion control and two control treatments of topsoil (TS) and hydroseeding (HS) applied at 5 cm depth. The simulator produced 89% uniformity using ten Veejet 80100 nozzles at a target rate of 100 mm h-1. The surface runoff was collected after 5 minutes of rainfall (first flush) and during the last 30 minutes of rainfall (steady-state). The first flush mean runoff for GUC-5 treatment was significantly higher than all other treatments. All other treatments; 50% woodchips and 50% compost blend (ECC-1.3, ECC-5), and hydroseeding (HS) had significantly lower runoff and erosion rates compared to topsoil (TS) and compost manufactured topsoil (CMT) at first flush and steady-state. Furthermore, there were no performance differences between 1.3 cm and 5 cm compost applications at first flush or steady-state. The results of this project indicate that particle size, soil moisture capabilities, and time at which rainfall is applied affect surface runoff. TxDOT specification of using ECC at 5 cm depth on a max of 3:1 slope should be reconsidered. An ECC application depth of 1.3 cm was effective in reducing first flush runoff and interrill erosion rates.
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none- quan, Yu 02 August 2006 (has links)
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