The BETTER water quality model, created by TVA, was used to model the temperature and dissolved oxygen (DO) in Spring Hollow Reservoir. The water balance consisted of pump discharge from the Roanoke River, runoff, releases at the dam, leakage, and storage. The geometry of the reservoir was represented by four columns and a variable number of five-foot layers. Through a sensitivity analysis, the parameters that influenced temperature and DO the most were determined. Temperature was then calibrated to a subset of the 19-month simulation period by systematically varying the most sensitive parameters. DO was calibrated to the entire simulation period due to the young age of the reservoir and the inconsistent inflow rates and timing. The verification process showed that the model reasonably reproduced the seasonal temperature patterns. By varying the sediment oxygen demand temporally and spatially, the model depicted the gradual hypolimnetic oxygen depletion in the reservoir. The model results suggest that the inflow organics and subsequent settling and accumulation are key factors in the DO depletion rate. Therefore, to enhance water quality conditions in the reservoir, a monitoring system in the Roanoke River should be installed with filling carried out when water quality in the river is optimal. For future modeling purposes, this research indicated that the model was very sensitivity to meteorological data, especially in determining temperature. Thus, a weather station located at the reservoir would permit collection of more accurate meteorological data, leading to greater confidence in the interpretation of the model predictions. / Master of Science

För att en hållbar utveckling ska kunna nås enligt de 17 miljömålen från Paris krävs en enkel och billig metod för vattenrening. Denna rapport behandlar en relativt oprövad metod som innebär att man ska rena metallförorenat vatten med hjälp av adsorptionsytor hos biomassa. Syftet med rapporten är att ta reda på ifall koppar- och koboltjoner skulle kunna bindas till vassväxten Cyperus papyrus och bomullsväxten Imperata cylindrica. Hur konkurrensen mellan kopparn och kobolten påverkar adsorptionen till biomassan samt vilken av biomassorna som lämpar sig bäst för rening skall också fastställas. Området som granskades var den koppar- och koboltförorenade floden River Nyamwamba i Uganda vilket gjorde att metallerna koppar och kobolt studerades. Biomassorna Cyperus papyrus och Imperata cylindrica växer i stor utsträckning i Uganda så dessa valdes ur ett hållbarhetsperspektiv då eventuella transporter kan minimeras. Adsorptionsförmågan av metallerna bestämdes genom en laboration där biomassorna kunde adsorbera mellan 45,55 - 69,84 % av kobolten och 63,74 -77,54 % av kopparn hos de fyra olika lösningarna som testades. Imperata cylindrica visade sig ha en något bättre adsorptionsförmåga. Möjliga metoder som skulle kunna implementeras i samhället kan vara filter tillverkade av biomassa men det krävs fortfarande mer forskning inom området innan dessa kan tas i bruk.

Rening av avloppsvatten är en viktig samhällsfunktion med höga krav på reningskapacitet och effektivitet, men traditionella reningsme- toder kräver mycket energi. Med anledning av detta har avloppsrening med mikrobiella bränsleceller (MFC) blivit ett stort forskningsområde. En MFC använder sig av nedbrytande mikroorganismer i en elektroke- misk redoxreaktion och kan därför användas för rening av avloppsvatten samtidigt som elektrisk energi kan utvinnas. I den här litteraturstudien sammanfattas den senaste forskningen kring hur de hinder som åter- står för storskalig avloppsrening med MFC kan överbryggas. Hindren är både ekonomiska och driftstekniska och tyngdpunkten i denna studie ligger på kostnadseffektivitet och ekologisk hållbarhet samt vilken roll det är rimligt att MFC kan anta i framtidens avloppsreningssystem. Det analyserade forskningsmaterialet antyder att den mest kostnadseffektiva grundkonfigurationen av MFC för avloppsrening är membranlös och fri från kostsamma katalysatorer. Att utnyttja biologiska sätt att underlätta redoxreaktionen, såsom att använda sig av bioanod, biokatod och luftka- tod, är både ekonomiskt och ekologiskt hållbart jämfört med traditionell MFC-teknik. Vidare har forskning kring användning av naturmaterial samt kol-, metalloxid- eller polymerbaserade nanomaterial visat på lo- vande resultat, men mycket arbete återstår innan MFC-tekniken till ful- lo är både driftsäker och kostnadseffektiv. Sammantaget visar resultaten att MFC-forskningen kring ekonomiskt och ekologiskt hållbara material och konfigurationer gjort vissa framsteg de senaste åren, samt att dessa bör utnyttjas i sammanhang där MFC integreras med beprövad renings- teknik, såsom membranbioreaktorer eller konstgjorda våtmarker, för att öka möjligheterna till att finna ett ekonomiskt och ekologiskt hållbart avloppsreningssystem. / Wastewater treatment is a crucial function in the urban society. With increasing population the need for energy efficient and ecologically sus- tainable solutions for water recovery will grow. Microbial Fuel Cells (MFC) are a promising technique with a potential to contribute to solv- ing this task, which is why they have been under extensive studies for several years in the context of wastewater treatment and energy recov- ery. A MFC designed for wastewater treatment consists of an electrolysis cell that uses wastewater as electrolyte, turning the chemical energy into electrical energy whilst microbes digests the nutrients and organic sub- stances. Some specific microbes, electrochemically active bacterias, are capable of anaerobic digestion and when the organic loadings are con- sumed, electrons and protons are released and a current can be collected from the fuel cell. This paper is a review of the most recent research focused on solving the critical problems that still prohibit a large scale usage of MFC for wastewater treatment. The most prominent issues are related to high initial costs och operational stability and the aim of this study is to summarize the state of art regarding cost effective materials and configurations and also to discuss what the future role of MFC in wastewater treatment might be. Due to the limited format only the eco- nomical and ecological aspects of sustainability is regarded. The results from this review indicates that the most cost effective basic configuration of MFC is membranless and free from expensive catalysts. Many studies show that the use of biological catalysts, such as microbial biofilm on the electrode surfaces, is a low-cost and effective way of stimulating the oxidation-reduction-reactions that drives the MFC. Also the use of air- cathodes, where the cathode is exposed to the air in order to stimulate oxygen reduction, instead of energy consuming air pump, is a promising way forward. Recently the use of natural materials, such as loofah and clay ware, have been studied with various results, and if the operational stability and overall performance could be enhanced this might well be a sustainable rout in research. Another strong trend is the use of cole-, metaloxide- or polymerbased nanomaterials which have a documented ability to increase both electric and purifying efficiencies, but the ecolog- ical sustainability regarding nanomaterials is a complex question which is not answered in this paper. Altogether, the research covered in this work shows that large scale wastewater treatment with MFC alone not at all is near at hand. However, some minor improvements have been made regarding cost effective and ecologically sustainable materials and con- figurations for MFC, and these findings could well be used in a context where MFC is integrated with other techniques, such as a Membrane Bio Reactor or Constructed Wetland, in order to take advantage of the syner- gistic effects that has been noticed in several studies. This might be the most reasonable role for MFC to play in the future wastewater treatment business, thereby contributing to the global strive for sustainability.

The construction of buildings and paved surfaces changes the natural water balance. Precipitation generates surface runoff and storm water instead of infiltrating into the soil. Storm water has come to be considered as a major source of pollution in lakes and streams in the vicinity of urban areas. Reduction of pollutants in storm water is a key action in order to protect sensitive recipients and maintain high water quality. Storm water is traditionally transported by storm sewers to the nearest recipient. In recent years the approach to storm water management has changed; storm water should primarily be disposed of on site, through local disposal of storm water, LOD. LOD is created by a combination of the function of several smaller local facilities and the general sewer system. In LOD techniques like wet and dry ponds, ditches, rain gardens, infiltration areas and green roofs are used. The function of a LOD facility is reduction, equalization and delay of storm water flows. There are several advantages of LOD over traditional storm water management. The natural water balance is imitated, exposed water surfaces and green areas are perceived as aesthetically pleasing, a reduction of pollutants occurs and the load on the grid is reduced The aim of this work was to investigate the conditions and strategies for increased use of LOD in existing urban areas in Västerås. This was done by examining two areas in Västerås city center and by suggesting LOD solutions. Private land and public land has been distinguished between for each area. The LOD plant is dimensioned so that the total outgoing flow is limited to 10 l / s, hectare. It has been investigated if the requirements for outbound flows from private property can be set lower and flows reduced by a further delay on public land or if it is more advantageous to delay the flows individually. To simulate flow and magazine volumes, the program StormTac has been used. The investigation has shown that storm water volumes to be disposed will be much lower if the disposal is done in one step. Available lawns should be used wherever possible to construct dry ponds, swales or other technics based on infiltration. By using lawns, large volumes can be disposed, pollution is reduced effectively and the arrangement is relatively cheap. Rain gardens are more expensive to construct but provide an efficient cleaning of storm water and are nice from an aesthetic point of view. Rain gardens should be placed lengthwise along roads or pedestrian streets. With such a design, large storage volumes are created while the surrounding areas can still be used. The use of percolation basins are needed when using LOD in urban paved areas. With the use of LOD plants, pollutants are reduced enough to reach the values and goals in Västerås’ storm water plan.

Stockholms länsstyrelse genomför en regional miljöövervakning för att kartlägga kvaliteten på grundvattnet. Det här arbetet har tagits fram på länsstyrelsens initiativ tillsammans med Kungliga Tekniska Högskolan och vars syfte har varit att identifiera och diskutera lösningar på eventuella kvalitetsproblem.   Undersökningen har varit fokuserad på kloridhalter i vattnet och en fallstudie har gjorts av Hammarby källa i Upplands Väsby norr om Stockholm. Det finns flera tidigare undersökningar om förorening kopplat till vägsalt, och den här studien har avgränsats till klorid och i mindre utsträckning andra ämnen som kan relateras till vägsaltning. Arbetet har inneburit en sammanställning och granskning av material om kloridhalter i grundvatten, lagstiftning om föroreningar, halkbekämpning och åtgärder mot vattenföroreningar.   Undersökningen visade att kloridhalten i källorna i Stockholmsregionen har ökat, med förhöjda värden i vissa enstaka källor. År 2014 var medelvärdet och medianvärdet på 51,6 respektive 24,4 milligram klorid per liter vatten. Vatten får kvalitetsanmärkningar och kan orsaka korrosionsproblem i ledningar när halten går upp till 100 milligram per liter. Dock ska åtgärdsprogram införas redan vid en kloridhalt på 50 mg/l eller vid en markant stigande trend av kloridhalten. Kloridkoncentrationerna i Hammarby källa har länge legat nära eller över 100 mg/l. På grund av de höga koncentrationerna tätades dikena intill vägen och saltningen minskade i området. Det har lett till att kloridhalten i vattnet har sjunkit, men väldigt långsamt, och halterna betraktas fortfarande som höga.   Det finns ett flertal åtgärder för att minimera kloridhalter i grundvatten, dels alternativ till natriumklorid eller andra metoder, t.ex. att hålla vägbanorna isfria med bergvärme. De är många gånger dyra och lättast att tillämpa vid konstruktion av nya vägar. Resultaten från undersökningen kan utgöra en grund för mer detaljerade undersökningar, både av specifika källor, möjliga åtgärder som kan genomföras och vilka andra föroreningar som förekommer i grundvattnet i Stockholmsområdet. / The Stockholm county administrative board is continuously perform regional environmental monitoring with regards to groundwater quality. The county board and the Royal Institute of Technology developed this project, and its aim was to survey the situation based on chemical analysis and discuss solutions to potential problems.   The study has focused on chloride concentrations in the groundwater and the Hammarby spring, situated in Upplands Väsby north of Stockholm, was used as a case study. Earlier, chloride concentrations had been studied in connection to deicing salts, and this study has been limited to chloride with some attention paid to other elements affected by deicing salts. The study has resulted in a summary and discussion on research on chloride in groundwater, laws regulating pollution, deicing efforts and countermeasures aimed at water pollution.   The study showed that chloride concentration has increased in springs found in the greater Stockholm area, with elevated concentrations found in specific sites. The overall concentrations are below the ones found in legal guidelines. 2014 showed a mean and a median on 51.6 and 24.4 milligrams of chloride per liter of water, respectively. Sampled water gets remarks on quality and cause corrosion in pipes at concentrations higher than 100 mg/l. The chloride concentration in the Hammarby spring has for a long been at or above 100 mg/l. Due to the high concentrations of chloride, the roadside ditches have been sealed and road salting has been limited. This has caused chloride concentrations to decrease slowly, but the concentrations are still regarded as high.   There are numerous kinds of countermeasures, both alternatives to deicing salts to decrease pollution or other methods, such as keeping roads free of ice through energy storage in the ground. These are often expensive and easier to implement when constructing new roads. The results from the project may be the base for more investigations, both with regards to specific springs and the countermeasures that can be used, and what other pollutants that are present in the groundwater in the Stockholm region.

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 373-387). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 373-387). Also available on the Internet.

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Hypersol-Macronet™ polymers have been evaluated for the adsorption of organic pollutants from aqueous solution. The adsorption performance of the polymers was compared with a commercial activated carbon, Chemviron F -400. Investigation into the physical structure of the adsorbents was performed using microscopy and the adsorption of nitrogen at liquid nitrogen temperatures. A critical analysis of the adsorption isotherm data reduction models is given. The polymers possess a bimodal pore size distribution of micropores, approximately l3A in diameter, and macropores, greater than 200A. The surface functionality of the Macronets, determined by diffuse reflectance IR, 13C NMR and X-ray photoelectron spectroscopy, is presented. Elemental analysis and direct titration techniques were also investigated. Relatively high concentrations of oxygen containing functional groups were observed on the polymers, attributed to ethers, alcohols and ketones formed during polymer production. Adsorption isotherms are given for the removal of phenol and three chlorophenols substituted in the ortho, meta and para position. The greater hydrophobicity of the chlorinated phenols resulted in stronger interaction energies and larger adsorption capacities. Batch kinetic data for the above adsorbates was modelled using the homogeneous surface diffusion correlations. Analytical techniques were developed and validated for the determination of trace levels (0.1 parts per billion) of five pesticides; atrazine, simazine, isoproturon, diuron and chlorotoluron. Single and multi-component adsorption isotherms are presented for trace concentrations of pesticides in aqueous solution. Mini-column breakthrough curves are presented for MN-200 and F-400. Selectivity of the polymers for the various pesticides was explained by differences in molecular size and the hydrophobicity of the adsorbates. The primary adsorption mechanism is hydrophobic interaction enhanced by hydrogen bonding. The negative influence of natural organic matter (NOM) on the removal of pesticides was investigated using batch and column techniques. The uptake of NOM on activated carbon is much greater than that on MN-200. Total regeneration ofMN-200 using a variety of organic solvents was achieved for high and low solid phase concentrations of pesticides. Regeneration of F-400 was ineffective. The breakthrough point of a regenerated mini-column containing MN-200 was identical to the virgin polymer data. The potential commercial application of the resin for the purification of drinking water is discussed.

Rapid gravity filters used in the treatment of drinking water are subject to small continuously occurring flow rate fluctuations known as surges. Large, step changes in the rate of flow have been shown to have a detrimental effect on filtrate quality. However, less is known about the effects of surging flow on rapid filter performance. Measurements by previous researchers have found that surges from 2 to 10 % of the flow rate are common and can occur as many as one hundred times per minute. It has been suggested that surging may significantly influence rapid filter performance but the effect has yet to be confirmed under well-controlled conditions and the mechanisms critically examined. Measurements taken by this author at local water treatment plants confirmed the presence of surging flow in the rapid gravity filters of a similar nature to other researchers' findings. Evidence suggested the degree of surging present was related to the design of the filtrate piping and some design recommendations are made on this basis. Two rapid gravity filters were developed in the laboratory to investigate the influence of surging flow on filter performance. The filters were constructed from Perspex pipe and comprised 600 mm of 0.5 to 1.0 mm filter sand. The filters were operated at 30°C at an approach velocity of 8.0 metres per hour with a test suspension of PVC particles. Reproducible performance was established before applying surges to one filter only. A range of surging characteristics similar to those observed at full-scale plants was applied during the test programme. Measurements of head loss and turbidity were taken at a range of depths within the filter media periodically during each test. Samples were collected for particle size distribution analysis from selected tests. The surging flow was found to inhibit the performance of the laboratory filters. The fluctuations in flow rate were found to reduce the removal efficiency of turbidity' and retard the rate of head loss development. The surges were found to inhibit the removal of all particle sizes present in the test suspension. The magnitude of the effect on filter performance was found to be dependent on the magnitude and frequency of occurrence of the surges applied. The experimental results obtained suggest that surging does have an effect on full- scale rapid filter performance and has implications for drinking water quality.