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Fosforavskiljning i reaktiva filter vid småskalig avloppsrening / Reactive Filter Materials for Removal of Phosphorus in Small Scale Wastewater Treatment PlantsStark, Therese January 2004 (has links)
<p>An excessive input of nutrients to lakes and other water bodies has created a problem with eutrophication in Sweden. Untreated, or partially treated, domestic sewage is a major source for discharge of phosphorus (P), which is the nutrient most frequently responsible for eutrophication of most fresh waters and the Baltic Sea. The waste water can be cleaned by filter materials, which have a high P-retention ability and which after saturation may be used as fertilizers. Four potentially suitable filter materials were tested in batch- and column experiments in this study. In the batch experiments, the following materials were shaken with waste water in time series ranging from 5 seconds to 60 minutes: coarse (1-4 mm) and fine (0-2 mm) Polonite® (heated bedrock from Poland); Filtralite® (light expanded clay aggregates with limestone added before burning); water cooled blast furnace slag (BF-slag) and BF-slag mixed with 10% burned limestone. In the column experiment, the phosphorus sorption capacity in BF-slag and BF-slag mixed with burned limestone was observed under saturated and unsaturated flow conditions for 10 weeks. The waste water used in both experiments originated from the full scale testing site at Ångersjön in Sweden. After the column experiment was ended, the filter materials were investigated with XRD (X-ray diffraction) and SEM (scanning electron microscope) in order to figure out which chemical reactions that had taken place.</p><p>The results from the batch experiments show that fine Polonite® and BF-slag mixed with limestone have the fastest P sorption capacity. Already after 5 seconds of shaking the materials showed effective retention of P. The coarse Polonite®, Filtralite® and BF-slag showed similar sorption capacities, although the coarse Polonite® tended to be somewhat inferior. The column studies showed that the materials used in the columns had a sorption capacity of 98 % or more. The XRD and SEM indicated that an amorphous calcium-P-compound was created in the filter material.</p> / <p>I Sverige är reningen av fosfor i vatten från enskilda avlopp ofta bristfällig, vilket bland annat kan leda till övergödning av sjöar, hav och vattendrag. Sedan några år tillbaka har olika filtermaterial med speciella reaktiva egenskaper, som bland annat avskiljer fosfor från avloppsvatten, undersökts. Tanken med filtermaterialen är att de efter mättnad med näringsämnen ska kunnas användas som jordförbättringsmedel. I denna rapport har några olika filtermaterial, lämpade för fosforavskiljning, undersökts genom skak- och kolonnförsök. I skakförsök, där skaktiderna varierade mellan 5 sekunder och 60 minuter, testades Polonite®, Filtralite®, Hyttsand och Hyttsand blandad med 10 % bränd kalk. Polonite® är en upphettad form av bergarten opoka varav två olika kornstorleksfraktioner (0-2 mm och 1-4 mm) användes. Filtralite® och Hyttsand är antropogena filtermaterial. Filtralite® tillverkas i Norge och består av kalkhaltiga kulor av expanderad lera (Leca®). Hyttsand framställs genom vattenkylning av masugnsslagg som bildas vid framställningen av råjärn vid stålverket i Oxelösund. I kolonnförsöken, som utfördes under 10 veckor, studerades Hyttsand och Hyttsand blandad med 10 % bränd kalk under omättade och mättade flödesförhållanden. I samtliga experiment användes avloppsvatten från reningsverket vid Ångersjön, där Filtralite® och Hyttsand testas i fullskala. Efter kolonnförsöken avslutats undersöktes filtermaterialen med XRD (röntgendiffraktion) och SEM (svepelektron mikroskop) för att utreda vilka mekanismer som medverkat vid avskiljningen av fosfor.</p><p>Resultaten från skakförsöken visade att finkornig Polonite® och Hyttsand blandad med kalk avskiljer fosfor effektivt redan efter skakning i 5 sekunder. Grovkornig Polonite, ren Hyttsand och Filtralite® sorberade fosfor tämligen likartat, även om den grovkorniga Poloniten® tenderade att vara aningen sämre än de övriga. Resultaten från kolonnförsöken visade att fosfor kunde avskiljas till över 98 % i alla kolonner och att det bildats amorfa fosfatföreningar, främst med kalcium, under den 2,5 månader långa experimentperioden.</p>
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Diffuse minewater pollution : quantification and risk assessment in the Tamar catchmentTurner, Alison Jean May January 2011 (has links)
Abandoned metal mines in the Tamar catchment, south west England, represent a significant threat to surface water quality via generation of acid mine waters. Currently the River Tamar fails environmental quality standards (EQS) established under the Water Framework Directive (2000/60/EC) for dissolved Cu (x ̅ = 0.19 ± 0.05 μmol L-1) and Zn (x ̅ = 0.19 ± 0.06 μmol L-1, both 1997-2007) downstream of historic mining area of Gunnislake. The aim of this study was to quantify the risk to surface water quality by diffuse drainage generated by mine waste tips. For the first time, a GIS model was compiled and used to generate a priority list of known areas of mine waste, based on physical and environmental factors. The methodology was consistent with European guidance documentation published to meet the requirements of the Mining Waste Directive (2001/21/EC) and has since been applied, in a modified form, to other catchments in south west England. Two study sites, with contrasting mineralogy and hydrology, scored highly in the model and were the subject of field investigations from 2007-2009. These were Devon Great Consols (DGC), an abandoned Cu-As mine near Gunnislake and Wheal Betsy (WB), an abandoned Pb-Ag mine, near Mary Tavy. At each site, surface waters and shallow groundwaters were sampled and analysed for dissolved metals (including Al, Cu, Zn, Mn, Pb, Ni, and Cd), metalloids (As, Sb), major ions and anions. Samples of four selected mine waste tips were also gathered and subjected to a range of laboratory leaching experiments including the novel application of a dynamic upflow percolation test, based on an existing European method (CEN TS 14405). Leachates generated by the waste tips in the field were highly variable and elevated with respect to EQS for Al (up to 1850 μmol L-1), Cu (570 μmol L-1), Zn (34 μmol L-1), Ni (3.8 μmol L-1), Cd (0.17 μmol L-1), Mn (216 μmol L-1), Fe(537 μmol L-1) , As (380 μmol L-1) and Sb (5.4 μmol L-1). Estimated annual fluxes of dissolved metals were predicted using average rainfall data and catchment areas calculated in ArcHydro9 to estimate the annual discharge of waters from the tip. These calculations showed annual contaminant flux from the tips to exceed, or be of the same order of magnitude to, major adit discharges in the catchment (e.g. Cu 50900-66900 mol y-1 at DGC and 470 mol y-1 Cd at WB) and represented a significant contributor to metal flux in the Tamar catchment. Primary sulphide minerals in the waste were generally highly altered and metals (Pb, Cu, Zn, and Mn) and As were found to be strongly associated with secondary iron minerals, precipitated under oxic conditions. In finer wastes, sorption to clay minerals was also found to be very important for the retention of dissolved metals, particularly Pb. Concentrations of contaminants in column field leachates were similar for most metals (Cu, Zn, Mn, Ni and Cd) and may provide a useful tool for prediction of leachate composition. However, sorption and release of metals and As to the secondary phases and clays were highly sensitive to pH change and where laboratory experiments did not replicate field pH, discrepancies between in situ and laboratory results were observed up to two orders of magnitude in scale (particularly for As and Pb).
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Electro-Disinfection of Municipal Waste Water using Direct CurrentAcosta Vega, Julio A 18 December 2014 (has links)
Wastewater treatment has always been a problem to human settlers. Events such as the great stink of London during the summer of 1858 have pushed engineers into developing new technologies to deal with such wastes in effective and safe ways. Research projects like this aim to find ways of improving performance, economics, or environmental friendliness of treatment and disinfection methods.
This thesis deals with the effectiveness, mechanisms of action, by-products and side effects of using DC current to disinfect secondary effluent. It is proposed as an alternative to conventional methods, such as chlorination, which are not always environmentally friendly or feasible.
It was demonstrated that DC current efficiently kills pathogens. DC properly used achieves disinfection significantly higher than the minimum required by the EPA. Nevertheless disinfection by products such as residual chlorine should be taken into account when considering this technology as an alternative to conventional chlorination.
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Determination of volatile organic compounds in ambient air by using thermal desorber, sorbent tubes, canister and GC-MSMkhwanazi, Sipho Sydney 06 1900 (has links)
M. Tech. (Chemistry, Department of Chemistry, Faculty of Applied and Computer Science), Vaal University of Technology / The dissertation deals with volatile organic compounds that evaporate from the water-oil
separate in the refinery, which causes bad odour around the neighbouring communities, the existence of these compounds are being identified and quantified in different seasons for the year.
VOC are emitted whenever wastewater is exposed to the atmosphere. As such, emission points include open drains ditches, manhole sewer outfalls and surface fore bays, separators and treatment ponds. Refinery units such as reactors, fractionators are periodically shutdown and emptied for internal inspection and maintenance. The amount of VOC entering the wastewater is not monitored. The effluent water discharged from the refinery is not checked for the amount ofVOC present. The monitoring of the amount of VOC in wastewater stream may lead to a decrease in the emission. From the quantified results at different season, the summer session has the highest VOC emission due to the heat that causes more vapours.
The preparation of a method for determination of VOC's in air presents many difficulties,
because of their high volatilities and low concentrations in air. As well, the results of
determination are affected by the properties of the sorbent used, mainly its sorption capacity, depending on the properties of the compound under determination. The methods for sampling and analytical procedures for the measurements of volatile organic compounds that are hazardous to air pollution are compendium method T0-14 and sorbent tube method compendium T0-17. Both methods (sorbent tube and canister) differ from each other in their extraction and detection techniques. The well suitable method for the VOC determination is canister method; this method gives more representative sample of the ambient monitoring of 24 hours, where as sorbent tube can do for 2 hours only. The canister method is more advantages due to the sample that will be still remaining for further analyses or re-check.
The integrity of API water-oil separator has been improved to cause less evaporation during high temperature season. As the temperature drops from season to season, the VOC also comes down as its being seen in this study that on the winter results that all the VOC were below 90 1-lg/kg. / National Petroleum Refiners of South Africa laboratory
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Estudo do escoamento em condutores horizontais de sistemas de coleta de esgotos sanitários de edifícios residenciais. / Study of the flow in horizontal conductors of waste water systems of residential buildings.Oliveira, Lúcia Helena de 22 May 1991 (has links)
Os condutores horizontais dos sistemas de coleta de esgotos sanitários, no Brasil e em quase todos os países do mundo, tem sido dimensionados considerando-se o escoamento em regime permanente, o que na realidade não ocorre. Sabendo-se que o escoamento no interior destes condutores acontece em regime não permanente, caracterizado pelo movimento de ondas, devido a aleatoriedade de uso dos aparelhos. Neste trabalho, apresentamos o estudo do escoamento não permanente, verificado, nos ramais e coletores dos sistemas de coleta de esgotos sanitários de edifícios residenciais. As equações diferenciais da continuidade e da quantidade de movimento, que regem este escoamento, são resolvidas pelo método das características. Apresentamos, também, os resultados e análise de várias simulações do programa de computador desenvolvido com base no método das características pelo professor Swaffield, da Universidade Heriot-Watt, Escócia. Os dados de entrada para estas simulações foram obtidos a partir de ensaios laboratoriais de algumas configurações de ambientes sanitários brasileiros, também apresentados neste trabalho. Os resultados destas simulações mostram que a consideração do escoamento em regime não permanente, possibilita a redução dos diâmetros dos ramais e coletores, e consequentemente, a redução dos custos destes sistemas. / Usually horizontal waste pipes of Building Drainage Systems, in Brazil and almost all of countries in the world, are dimensioned considering a steady flow, that does not exist. The random use of the sanitary appliances connected to the Drainage Systems of the building is the responsible for the unsteady flow. We present a study of unsteady partially filled pipeflow for drains and sewers. The differential equations of continuity and motion are solved via the method of characteristics. We present, also, the results and analysis of several simulations using a computational program developed by Prof. Swaffield-Heriot - Watt University, Scotland. The data entry were obtained through laboratorial tests which considered brazilian bathroom configurations, presented in this work. The results show us that the consideration of unsteady flow conduct to the reductions of horizontal waste pipes diameters, consequently to the reduction of the Building Drainage Systems costs.
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Traçadores ativáveis de índio e terras raras para estudos do desempenho de instalações de tratamento de efluente / Indium and rare earth activable tracers for the evaluation of waste water plant performanceGilmara Lúcia Souza Alvarenga 31 August 2012 (has links)
Estudos de novos sistemas de tratamento de águas residuais vêm crescendo
mundialmente. Os esforços para avançar e aprofundar os conhecimentos sobre os
processos de eliminação de impurezas da água em seu estado bruto natural, bem como
para otimizar tecnológica e economicamente as operações envolvidas, são uma resposta
ao desafio, cada vez mais premente, de proporcionar às populações urbanas e rurais a
utilização em quantidades e qualidade adequadas deste recurso fundamental para a vida
no planeta.
Dentre os vários tipos de processos para a depuração das águas servidas, este
estudo enfoca aspectos físicos dos sistemas conhecidos como wetlands e de uma
determinada modalidade de reator biológico anaeróbio.
Os sistemas conhecidos como wetlands, que são um aperfeiçoamento mais
controlado de processos que existem na natureza, têm um papel de destaque na
eliminação de impurezas transportadas por efluentes.
Os reatores biológicos contemplados neste estudo são do tipo anaeróbio de fluxo
ascendente, mais conhecidos pela sigla UASB correspondente às iniciais de sua
designação em inglês (upflow anaerobic sludge blanket), que estão sendo cada vez mais
utilizados para tratamento de efluentes urbanos. Eventualmente seus efluentes
necessitam de tratamento posterior que será realizado nas wetlands.
Todo processo tecnológico demanda constante aperfeiçoamento de seu
desempenho. As melhorias são propostas com base na observação e avaliação do
desempenho, dos sistemas de tratamento de água, que têm componentes físicoquímicas,
biológicas e hidráulicas. O desempenho hidrodinâmico do reator (UASB) e da
wetland plantada foram o objeto desse estudo. O objetivo foi utilizar a metodologia dos
traçadores conjugada com as técnicas de análise de respostas a impulsos em sistemas.
Foram empregados traçadores radioativos (bromo, tecnécio e trítio) e ativáveis (DOTAIn,
DOTA-Eu, DTPA-In, DTPA-La, DTPA-Sm e DTPA-Eu) e seus resultados tratados
e analisados por softwares apropriados.
Os resultados indicaram que os traçadores ativáveis testados têm potencial para
serem utilizados nos sistemas hidráulicos naturais ou artificiais.
Palavras-chave: tratamento de águas residuárias, wetland, reator UASB, traçadores
ativáveis. / Research and development of novel spent water treatment processes are
increasing worldwide. A large amount of effort is directed towards the advancement and
deepening of the knowledge concerning elimination of water contaminants, as well as
optimization of the processes required to that end, both from the technological and the
economic viewpoints. Such activities aim to meet the increasingly challenging need of
providing water in large quantities and adequate qualities to urban and rural
communities.
Among the several processes presently available for the treatment of natural
water resources, and especially for treatment of wastewater, the present study focused
on systems known as wetlands and a special concept of biological reactor. It focuses in
the selection of tracer techniques aiming at the observation and evaluation of the
performances of such systems.
Treatment in wetland systems constitute a reproduction at a more controlled
level, of processes occurring in nature. They play an outstanding role in eliminating
effluent-borne impurities and contaminants.
The biological reactors assessed in this study are of the anaerobic type with
upward internal flow. These are better known as UASB reactors, an acronym for upflow
anaerobic sludge blanket, and are being increasingly employed in processing urban
wastewater. Nonetheless, their effluent may eventually require a further polishing,
which can achieved by flushing them through a wetland system.
The performance of any technological process requires a continuous
improvement. This improvement is based on the observation, measurement and
evaluation of the state of art of the process. In the present study tracer techniques have
been coupled with system impulse-response analysis methods. A novel kind of tracer,
the activable tracer, was tested and assessed by comparison with radiotracer
performance. The results obtained with both activable and radioactive tracers have been
processed and analyzed by appropriate software.
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The purification of industrial wastewater to remove heavy metals and investigation into the use of zeolite as a remediation toolSalih, Ali Mohammed January 2018 (has links)
Zeolites are well-known aluminosilicate minerals that have been widely used as adsorbents in separation, purification processes and environmental pollution control. Zeolites are used in various industrial applications due to their high cation-exchange ability, molecular sieve and cataltic properties. In order to reduce the costs of acquisition and minimise the disposal of adsorbents, both modified natural zeolite and synthetic zeolite (derived from kaolinite) were used for the purification of wastewater. The characteristic properties and applications of adsorbents are also discussed including the advantages and disadvantages of each technique. The present work involves the study of the removal of Cu2+, Fe3+, Pb2+ and Zn2+ from synthetic metal solutions using natural zeolite. Laboratory experiments were used to investigate the efficiency of adsorbents in the uptake of heavy metals from industrial wastewater. These include equilibrium tests, kinetic studies and regeneration studies. The physical and chemical characterization of the zeolites was carried out using different analytical techniques such as Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), X - Ray Diffraction (XRD), X - Ray Fluorescence (XRF), Thermogravimetric Analysis (TGA), Fourier Transform Infrared (FT-IR) Spectroscopy and Inductively Coupled Plasma-Optical Emission Spectrometer (ICP-OES). The kinetic study indicated the suitability of the natural zeolite for the removal of Cu2+, Fe3+, Pb2+ and Zn2+ ions from synthetic wastewater. Batch experiments were used to identify the effect of parameters that affect the rate of adsorption such as the effect of adsorbent mass, effect of adsorbent particle size, effect of initial solution pH, effect of initial solution concentration, effect of agitation speed and effect of pre-treatment of adsorbent and evaluated their impact on the efficiency of the zeolite in the removal of heavy metals from industrial wastewater. The kinetic studies showed that the capacity of the adsorbents for the removal of heavy metals increased with a greater mass of absorbent, increased initial solution pH, increased agitation speed, higher solution concentration as well as the application of a pre-treatment. The results from the equilibrium studies positively demonstrated that natural zeolite can be used as an excellent adsorbent for removing heavy metals from multi-component solutions. The equilibrium experiments indicated that the capacities of natural zeolite for the uptake of heavy metals increased when the initial solution pH increased. The results indicated that the maximum removal capacities Q were 22.83, 14.92, 14.49 and 17.54 mg/g natural zeolite for copper, iron, zinc, and lead respectively. Both the Langmuir and Freundlich isotherm models were used to characterize the experimental data and to assess the adsorption behaviour of natural zeolite for copper, iron, lead and zinc. The experimental data were slightly better suited to the Langmuir isotherm than the Freundlinch isotherm. The value of the correlation coefficients r2 ranged from 0.93 to 0.99 for the Langmuir isotherm and from 0.90 to 0.99 for the Freundlich isotherm. The present work also involved the study of synthetic zeolite A, which was derived from natural kaolinite. The conversion of the raw materials into zeolitic materials was carried out in two ways: first, conventional hydrothermal synthesis and second, alkaline fusion prior to hydrothermal synthesis. The results from both routes show that zeolite A was synthesised successfully. Finally, the experiments show that both natural and synthetic zeolites can be available in commercial quantities. Synthetic zeolites are more attractive for some specific applications, while the cheapness of natural zeolite may favour its use.
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Land disposal of winery and distillery wastewatersChapman, Jeanette, 1960- January 1995 (has links) (PDF)
Bibliography: leaves 183-191. This thesis establishes a model for the treatment of organic materials in wastewaters produced by the wine industry, by irrigation of soils. Winery and distillery wastewaters were analysed to determine the origins and concentrations of the major organic and inorganic components.
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Enrichment of Methanogenic Microcosms on Recalcitrant Lignocellulosic BiomassLacourt, William 14 December 2011 (has links)
To improve biogas production from lignocellulosics, methanogenic microbial enrichments were prepared from moose rumen fluid, beaver droppings, and internal circulation (IC) reactor granules amended with cellulose, pine needles, lignosulphonate, tannic acid, and poplar hydrolysate. Tannic acid delayed methanogenesis compared to cellulose only enrichments, both by reducing initial rates (up to 50% in beaver dropping cultures) and increasing lag times (up to 50 days in moose rumen cultures). Biogas yields from poplar hydrolysate were 56 % by beaver droppings, 51% % by IC granules, and 31 % by moose rumen enrichments. Bacterial community profiles, determined via denaturing gradient gel electrophoresis (DGGE) showed divergent populations between enrichments. Enrichment on pine needles or poplar hydrolysate promoted bioconversion of post extraction wash (PEW), and beaver dropping enrichments fed pine needles equaled the yield (about 23%) from IC granules. Together, the DGGE and PEW results provide evidence of acclimatization to previously recalcitrant feeds.
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Enrichment of Methanogenic Microcosms on Recalcitrant Lignocellulosic BiomassLacourt, William 14 December 2011 (has links)
To improve biogas production from lignocellulosics, methanogenic microbial enrichments were prepared from moose rumen fluid, beaver droppings, and internal circulation (IC) reactor granules amended with cellulose, pine needles, lignosulphonate, tannic acid, and poplar hydrolysate. Tannic acid delayed methanogenesis compared to cellulose only enrichments, both by reducing initial rates (up to 50% in beaver dropping cultures) and increasing lag times (up to 50 days in moose rumen cultures). Biogas yields from poplar hydrolysate were 56 % by beaver droppings, 51% % by IC granules, and 31 % by moose rumen enrichments. Bacterial community profiles, determined via denaturing gradient gel electrophoresis (DGGE) showed divergent populations between enrichments. Enrichment on pine needles or poplar hydrolysate promoted bioconversion of post extraction wash (PEW), and beaver dropping enrichments fed pine needles equaled the yield (about 23%) from IC granules. Together, the DGGE and PEW results provide evidence of acclimatization to previously recalcitrant feeds.
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