Dissertations / Theses on the topic 'Mass balance'
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Gedye, Sharon Jane. "Mass balance in recent peats." Thesis, University of Liverpool, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266139.
Full textAndersson, Emil. "Online Metallurgical Mass Balance and Reconciliation." Thesis, Umeå universitet, Institutionen för fysik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-185252.
Full textI malmanrikning, är flotation en av de viktigaste och mest mångsidiga metoderna. Flotation utnyttjar de fysikaliska ytegenskaperna som partiklar av värdemineral har för att separera dessa från det mindre värdefulla gråberget i malmen. Krossad och mald malm blandas med vatten och matas in i flotationstankar. I flotationstankarna görs partiklarna av värdemineral hydrofobiska. På så vis kan de fästa sig vid luftbubblor och flyta till ytan och bilda ett skum. Detta skum samlas sedan ihop och behandlas vidare eftersom det innehåller en högre koncentration av värdemineral. Flotationskretsen styrs och underhålls med hjälp av mätningar av massflödena och halterna av de olika ämnena som finns i kretsen. På grund av ekonomiska, praktiska, och teknologiska hinder kan dessa mätningar bara göras på ett utvalt antal punkter i kretsen samt bara vid diskreta tillfällen. Felaktigt data kan ha förödande konsekvenser om operatörerna lämnas med begränsad information och processen fortlöper med oupptäckta fel. Mätsäkerheten kan förbättras med hjälp av massbalansering och haltjustering. Traditionellt görs massbalansering genom att summera den totala massan som löpt genom kretsen samt medelvärden av halterna över lång tid för att undvika att räkna in den interna massan i systemet. Det är önskvärt att utföra massbalansering direkt för att möjliggöra snabbare ingrepp ifall fel uppstår i kretsen under den fortlöpande processen. Denna rapport beskriver en dynamisk lösning för massbalansering och justering av massflöden och halter i en flotationskrets. Här används fysikaliska modeller av kretsen för att konstruera bivillkor för massbalans med hjälp utav interpolation och testfunktioner och massbalanseringsproblemet ställs upp som ett optimeringsproblem. Optimeringen sker genom att justera mätserien så att residualen, skillnaden mellan det uppmätta värdet och det justerade värdet, minimeras under uppfyllande av mass balans. En implementation i MATLAB och tester på syntetisk data visar att den dynamiska formuleringen av massbalans justerar de felaktiga mätvärdena så att massbalans uppfylls. Med det resultatet i åtanke, finns det fortfarande viktiga aspekter av implementationen som bör tas hänsyn till. Modellen använder de okända och cellspecifika parametrarna flotationshastighet och utbytet och dessa måste kunna bestämmas för att denna modell ska kunna användas. Ett förslag på modellering av flotationshastigheten föreslås i rapporten. Dessutom ges förslag på strategier att hitta utbytet. Kraven på noggrannhet och snabbhet diskuteras också. Möjliga nästa steg för projektet är att vidareutveckla en tidseffektiv implementation genom att använda syntetiska data. Därefter kan en implementation för naturligt data verifiera modellerna.
au, taiga@westnet com, and John Rich. "Integrated Mass, Solute, Isotopic and Thermal Balances of a Coastal Wetland." Murdoch University, 2004. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20040520.130717.
Full textHuss, Matthias. "Past and future changes in glacier mass balance /." Zürich : ETH, 2009. http://opac.nebis.ch/cgi-bin/showAbstract.pl?sys=000256345.
Full textWiklund, Sara. "Long-term glacier mass balance of Nordenskiöldbreen, Svalbard." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-295789.
Full textDen globala uppvärmningen som sker just nu har en påverkan över hela jorden och glaciärer på Svalbard genomgår snabba förändringar som följd. På Svalbard har den årliga medeltemperaturen stigit sedan början av 1900-talet och i en klimatprojicering förväntas temperaturen att fortsätta stiga. Den glaciala massbalansen är viktig för att övervaka glaciärers respons till klimatförändringar. I detta arbete modelleras Nordenskiöldbreens massbalans från 1957 till 2016 med hjälp av en temperaturindex modell. Den meteorologiska data som används i modellen, nederbörd och temperatur, har mätts vid en väderstation i Longyearbyen sedan 1957. Med den långa tidsperioden i modellen blir långsiktiga trender i massbalans, nederbörd och temperatur tydliga. Massbalansen kan även korreleras mot temperatur och nederbörd, vilket ger viktig information om hur dessa påverkar glaciärers beteenden. De resultat som framkommer kan användas för att förutspå hur glaciärer förändras i framtiden med en klimatändring. I simuleringen har Nordenskiöldbreens massbalans en negativ trend, nederbörd har ingen trend och temperatur har en positiv trend. Det är temperatur som styr den långsiktiga massbalansen och den kortsiktiga mellanårs-massbalansen styrs av nederbörds fluktuationer.
Lauvdal, Anders. "Mass balance model for Hammerfest LNG plant Snøhvit." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-23363.
Full textSchwartz, Vegar. "Greenland ice mass balance using GRACE gravity data." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for bygg, anlegg og transport, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-24543.
Full textDepoorter, Mathieu A. "Mass balance investigation of Antarctica from budget methods." Thesis, University of Bristol, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.702166.
Full textHuss, Matthias Boes Robert. "Past and future changes in glacier mass balance /." Zürich : Versuchsanstalt für Wasserbau, Hydrologie und Glaziologie, ETH Zürich, 2009. http://opac.nebis.ch/cgi-bin/showAbstract.pl?sys=000263371.
Full textGreenfield, David W. J. "A local authority waste management mass balance model." Thesis, University of Brighton, 2010. https://research.brighton.ac.uk/en/studentTheses/2f7bca16-407c-44d0-a102-d03e3875e542.
Full textPeano, Daniele <1987>. "Simulation of Greenland mass balance evolution until 2100." Doctoral thesis, Università Ca' Foscari Venezia, 2015. http://hdl.handle.net/10579/8334.
Full textAkhand, Victoria. "Mass Balance Model of Impurities for the WoodRoll Process." Thesis, KTH, Skolan för kemivetenskap (CHE), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-215931.
Full textDe fossila bränslena beräknas vara förbrukade om 35 år för olja, 37 år för gas och 107 år för kol, räknat från år 2009. Användningen av fossila bränslen måste därför minskas genom övergång till förnybara resurser. Detta kommer i sin tur bidra till att motverka de fossila bränslenas negativa effekter på miljön, såsom den globala uppvärmningen. Termokemiska processer, som pyrolys och förgasning av biomassa, anses vara den mest effektiva tekniken för att omvandla biomassa till användbara energibärare. Cortus Energy AB är ett svenskt företag som har utvecklat en patenterad förgasningsteknik kallad WoodRoll ® för förgasning av biomassa. Aska i en termokemisk omvandlingsprocess kan ge upphov till korrosion, sintring, slagg samt förgiftning av katalysatorer vilket leder till operativa problem. Dessutom är tungmetaller såsom Zn, Pb och Cd miljömässigt relevanta. Dessa metaller bidrar till förorening av miljön, vilket i sin tur kan skada människor och ekosystemet via näringskedjan. De oönskade elementen bör därför identifieras för att minimera deras inverkan på den övergripande termokemiska processen och för att reducera utsläppet av dessa ämnen. Syftet med detta examensarbete, på uppdrag av Cortus Energy AB, var att undersöka möjliga nyckeltal som kan användas för att beskriva och förutse hur askan beter sig i deras patenterade WoodRoll® process. De nyckeltal som har undersökts teoretiskt är empiriskt utvecklade utifrån erfarenhet av förbränning av kol. Dessa nyckeltal används regelbundet av analysföretag på bränslen från biomassa trots att kunskapen om huruvida dessa faktiskt kan användas på biomassa är begränsad. För att säkerställa att användningen av dessa nyckeltal för aska från biomassa är korrekt måste de verifieras experimentellt i framtiden. Vidare görs en teoretisk undersökning för att studera vilka föreningar som möjligen kan bildas och i vilken fas detta sker. Denna undersökning visar att det inte finns en tydlig trend för hur de oorganiska elementen beter sig då olika studier har rapporterat motstridiga resultat. Vilka föreningar som bildas och i vilken fas i processen det i så fall sker beror på flera parametrar såsom temperatur, hastighet av uppvärmning, partikelstorlek, volatilitet, mängd samt interaktionen mellan de element som finns i biomassan. Arbetet avslutas med en massbalansmodell på utvalda oorganiska element för grenar och toppar, förkortat GROT, samt för bark. Detta kan bli ett verktyg för Cortus Energy AB för att identifiera ungefär hur mycket av varje element som finns i varje flöde WoodRoll®-processen. Modellen verifieras med analysresultat. Oorganiska element som påverkar processen och dess utrustning har valts för denna modell. Volymprocenten för H2, CO, CO2 and CH4 i modellen stämmer väl överens med de värden som Cortus Energy AB har erhållit. Detta visar att de termodynamiska jämviktsberäkningar är rimliga.
Rainville, Simon 1974. "A two-ion balance for high precision mass spectrometry." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/16934.
Full textIncludes bibliographical references (leaves 121-124).
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
This thesis describes the demonstration of a new technique that allows masses to be compared with fractional uncertainty at or below 1 x 10-11, an order of magnitude improvement over our previous results. By confining two different ions in a Penning trap we can now simultaneously measure the ratio of their two cyclotron frequencies, making our mass comparisons insensitive to many sources of fluctuations (e.g. of the magnetic field). To minimize the systematic error associated with the Coulomb interaction between the two ions, we keep them about 1 mm apart from each other, on a common magnetron orbit. We have developed novel techniques to measure and control all three normal modes of motion of each ion, including the two strongly coupled magnetron modes. With the help of a new computer control system we have characterized the electric field anharmonicities and magnetic field inhomogeneities to an unprecedented level of precision. This allows us to optimize the trap so that our measurement of the cyclotron frequency ratio is to first order insensitive to the field imperfections. Using the ions 13C2H2+ and 14N2+, we performed many tests of our understanding of the ions dynamics and of the various sources of errors in this technique. From these we conclude that there should be no systematic error in our measurements at the level of 5 x 10-12. Thus we feel confident reporting a value for the mass ratio of these ions with an uncertainty of 10-11.
(cont.) In this thesis, we also report measurements of the two mass ratios m[33S+]/m[32SH+] and m[29Si+]/m[28SiH+] with a relative uncertainty of less than 10-1l, which makes them the best known mass ratios to date. These can be combined with precise measurements of high-energy gamma-rays to provide a direct test of the relation E = mc2. This is a test of special relativity which does not rely on the assumption of a preferred reference frame. The uncertainty on the atomic mass of 29Si is also reduced by about an order of magnitude.
by Simon Rainville.
Ph.D.
da, Silva Cerozi Brunno, and Silva Cerozi Brunno da. "Phosphorus Dynamics, Mass Balance and Mineralization in Aquaponics Systems." Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/620832.
Full textFilipovic, Marko. "Mass balance of perfluoroalkyl acids in the Baltic Sea." Licentiate thesis, Stockholms universitet, Institutionen för tillämpad miljövetenskap (ITM), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-88779.
Full textAt the time of the defence the following papers were unpublished and had a status as follows: Paper 1: Manuscript
Arendt, Anthony Alan. "Approaches to modelling the mass balance of High Arctic glaciers." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq22565.pdf.
Full textSpikes, Vandy Blue. "A Mass Balance Study of the West Antarctic Ice Sheet." Fogler Library, University of Maine, 2003. http://www.library.umaine.edu/theses/pdf/SpikesVB2003.pdf.
Full textVernon, Christopher L. "Surface mass balance model intercomparison for the Greenland ice sheet." Thesis, University of Bristol, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.633454.
Full textRanasinghe, Milinda A. "Modelling the mass and energy balance in a compost biofilter." Thesis, University of Canterbury. Chemical and Process Engineering, 2003. http://hdl.handle.net/10092/7492.
Full textKunzen, Thomas. "HYDROLOGIC MASS BALANCE OF PERVIOUS CONCRETE PAVEMENT WITH SANDY SOILS." Master's thesis, University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3249.
Full textM.S.C.E.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Civil Engineering
Wong, T.-Y. "Mass balance of heavy metal pollution in a river catchment." Thesis, University of Manchester, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382893.
Full textVERA, YSRAEL MARRERO. "PREDICTING MERCURY CONCENTRATION IN TUCUNARÉ USING MASS BALANCE AND BIOENERGETICS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2004. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=6133@1.
Full textO mercúrio usado no garimpo do ouro na região amazônica é liberado para a atmosfera, solo e rios. Uma vez na atmosfera, o metal é oxidado e imediatamente se deposita. Na água, ocorre a transformação para o metilmercúrio principalmente pela ação de microrganismos. A formação do metilmercúrio aumenta a dispersão e biodisponibilidade do elemento no ambiente aquático. O metilmercúrio pode ser incorporado pelo plancton entrando, assim, na cadeia alimentar. A concentração do metal aumenta a medida que se ascende nos níveis tróficos da cadeia, atingindo os valores mais elevados em peixes carnívoros como o tucunaré. Dessa forma, as emissões de mercúrio provocam a contaminação dos recursos naturais e aumentam os riscos para a saúde dos consumidores habituais de pescado. O objetivo deste trabalho é testar um modelo de bioacumulação de mercúrio em peixes para estimar concentrações em predadores de topo da cadeia alimentar. O modelo pode ser usado como ferramenta para a gestão ambiental de ecossistemas aquáticos potencialmente contaminados com mercúrio. Este objetivo foi atingido através da combinação dos modelos de balanço de massa de Trudel e bioenergético de Wisconsin, aplicados em espécies tropicais do gênero Cichla (tucunaré) da bacia do rio Tapajós. O modelo bioenergético de Wisconsin foi usado para determinar as taxas de consumo de alimento a partir de dados de crescimento estimados. Os parâmetros usados nos modelos foram obtidos na literatura. A habilidade da modelagem na predição dos teores de mercúrio em tucunarés foi avaliada através da comparação com dados de campo obtidos nos anos 1992 e 2001, no rio Tapajós e no sistema de lagos Maicá. Os melhores resultados foram alcançados para os espécimes coletados no ano 1992, o que parece estar relacionado com uma melhor estimativa da concentração de mercúrio no alimento neste ano.
The mercury used in the artisanal mining (garimpo) of gold in the Amazon region is emitted to the atmosphere, soil and rivers. Once in the atmosphere, the metal is oxidized and immediately deposited. In the water, the transformation to methylmercury takes place mostly due to the action of microorganisms. The formation of methylmercury increases the dispersion and bioavailability of the element in the aquatic environment. The methylmercury can be assimilated by the plankton and enters the food chain. The concentration of the metal increases further up in the trophic levels of the chain and reaches the highest values in carnivorous fishes like tucunaré. Thus, the mercury emissions cause the contamination of natural resources and enhance the risks to the health of regular fish consumers. The objective of this work is to test a model for bioaccumulation of mercury in fishes. The model calculates concentrations in top predators of the food chain and can be used as a tool for the management of aquatic ecosystems potentially contaminated with mercury. This objective was accomplished through the combination of the Trudel mass balance and Wisconsin bioenergetics models, applied to tropical species of the Cichla (tucunaré) genre of the Tapajós river basin. The Wisconsin bioenergetics model was utilized to determine the rates of food consumption from estimated fish growth data. The parameters used in the models were found in the literature. The ability of the models to predict mercury contents in tucunarés was evaluated by comparison with the field data, obtained in 1992 and 2001, in the Tapajós River and in the Maicá lakes. The best results were attain ed for specimens collected in 1992 what seems to be related to a better estimate of mercury concentration in the food in this year.
BARRETO, GISELE DE OLIVEIRA. "MASS BALANCE DATA RECONCILIATION OF THE URUCU- MANAUS GAS PIPELINE." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2015. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=26316@1.
Full textCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
Se por um lado à privatização do setor de energia, que induz acirrada concorrência, tem estimulado a inovação tecnológica e a adoção de mecanismos de incentivos à eficiência operacional, a regulação do mercado introduz mecanismos de controle requerendo maior responsabilidade no uso consciente da energia de sorte a assegurar a eficiência energética e a proteção ambiental. Pressões de organizações ambientalistas internacionais e a crescente demanda por energia explicam a tendência mundial pelo uso de combustíveis fósseis mais limpos. O baixo nível de emissões e resíduos associados ao processo de combustão de gás natural qualifica esta commodity energética como um elemento estratégico para integrar a matriz energética de organizações e países comprometidos com a sustentabilidade global. O impacto econômico associado à medição de gás natural exige uma otimização do controle do balanço de massa no sistema de entrega. A aplicação da Metodologia de Reconciliação de Dados constitui o objetivo deste trabalho. A técnica provou ser uma ferramenta eficaz para a avaliação do balanço de massa em um gasoduto durante o período de operação associado ao transporte de gás natural. A natureza intrínseca do seu algoritmo de cálculo, que leva em conta a redundância nas medições, qualifica a metodologia para aumentar a confiabilidade da medição assim reduzindo a incerteza individual associada a cada grandeza física capaz de interferir na medição e identificar erros grosseiros. Fundamentado na avaliação metrológica do balanço de massa de um gasoduto brasileiro, os resultados do estudo permitem discutir a adequação da técnica proposta de reconciliação de dados. Dentre as conclusões do trabalho, foi possível mostrar que o uso da técnica de tratamento dos dados do gás não contado (unaccounted for gas) pode atingir valores inferiores a 0,3 porcento, comparando-se, assim, à tolerância preconizada em nível internacional.
If on the one hand, privatization of the energy sector, which induces keen competition, has stimulated technological innovation and the adoption of incentive mechanisms for operational efficiency, regulation of the market introduces control mechanisms requiring greater responsibility in the conscious use of energy so as to ensure energy efficiency and environmental protection. Pressure from international environmental organizations and the growing demand for energy, explain the worldwide tendency for the use of cleaner fossil fuels. The lower levels of emissions and residues associated with the combustion process of natural gas classify this energy commodity as a strategic element to enter into the energy matrix of organizations and countries committed to global sustainability. The economic impact associated with the measurement of natural gas, demands optimization in controlling the mass balance in the delivery system. Application of the Data Reconciliation Methodology constitutes the objective of this work. The technique proved to be an efficient tool for the evaluation of the mass balance in a gas pipeline for the period of operation associated with the transport of natural gas. The intrinsic nature of its calculation algorithm, which takes into account the redundancy of measurements, qualifies the methodology to increase the confidence of measurement, thereby reducing the individual uncertainty associated with each physical volume capable of interfering with the measurement and identify gross errors. Based on the metrological evaluation of the mass balance of a Brazilian pipeline, the results of the study enable discussion on the adequacy of the data reconciliation technique proposed. Among the conclusions of the work, it was possible to demonstrate that the use of the technique in treating the data of unaccounted for gas, could achieve values lower than 0.3 percent, thereby comparable with the tolerances advocated at international level.
Meister, R. "Estimating Antarctic ice sheet mass balance from gravimetry and altimetry." Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1364858/.
Full textRivera, Andres. "Mass balance investigations at Glaciar Chico, Southern Patagonia Icefield, Chile." Thesis, University of Bristol, 2004. http://hdl.handle.net/1983/987b1d4c-49ea-4dab-b53d-a054a453faa6.
Full textTaylor, Astrea. "Phosphorus mass balance for hypertrophic Grand Lake St. Marys, Ohio." Wright State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=wright1347933945.
Full textOkumura, Yutaka. "Mass Balance and Bioaccumulation of Major Dioxins in Sendai Bay." Kyoto University, 2011. http://hdl.handle.net/2433/135409.
Full textFang, Yuan-Hao, Xingnan Zhang, Chiara Corbari, Marco Mancini, Guo-Yue Niu, and Wenzhi Zeng. "Improving the Xin'anjiang hydrological model based on mass–energy balance." COPERNICUS GESELLSCHAFT MBH, 2017. http://hdl.handle.net/10150/625180.
Full textLuty, Mark. "Precision balances for measurement of mass and air density." Thesis, Brunel University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363465.
Full textFujita, Koji, and 耕史 藤田. "Effect of precipitation seasonality on climatic sensitivity of glacier mass balance." Elsevier, 2008. http://hdl.handle.net/2237/11360.
Full textDeBuhr, Christopher Leonard. "Metamorphic petrology and mass balance analysis in the Bugaboo contact aureole." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0019/NQ49488.pdf.
Full textDeBerardinis, Jeffrey T. Whalen Stephen Charles. "Nitrogen mass balance for spray fields fertilized with liquid swine waste." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2006. http://dc.lib.unc.edu/u?/etd,262.
Full textTitle from electronic title page (viewed Oct. 10, 2007). "... in partial fulfillment of the requirements for the degree of Masters of Science in the Department of Environmental Sciences and Engineering." Discipline: Environmental Sciences and Engineering; Department/School: Public Health.
Petroni, Ricardo N. (Ricardo Nicolas) 1971, and Peter H. (Peter Hampus) 1973 Israelsson. "Mass balance and 3D model of PAHs in Boston's inner harbor." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/50019.
Full textIncludes bibliographical references (leaves 192-199).
by Ricardo N. Petroni, Peter H. Israelsson.
M.Eng.
Burke, Megan Elizabeth. "Mass balance modeling of polychlorinated biphenyls in the Lower Duwamish Waterway." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/104192.
Full textCataloged from PDF version of thesis.
Includes bibliographical references (pages 30-31).
Remediation is most effective when a site is properly characterized. The Lower Duwamish Waterway (LDW) in Seattle, Washington is contaminated with polychlorinated biphenyls (PCBs). A zero dimensional mass balance of the 5 mile long waterway, which ends in Elliott Bay, helps to determine the different sources and concentrations of PCBs within the Lower Duwamish Waterway to aid future remedial activities. There are four unknown state variables: freshness, suspended sediment concentration, dissolved phase total PCB concentration, and sorbed phase total PCB concentration. The sole freshness source was the Green River and the freshness sink was the flushing at the downstream mouth. PCBs exist in sorbed and freely dissolved phases. Sorbed PCB sources include: the incoming Green River, laterals, and erosion. Sinks of sorbed PCBs include: deposition, flushing, and desorption. The Green River, laterals, diffusion, and desorption are all dissolved PCB sources, while the sinks are flushing and volatilization to the atmosphere. The calculated four state variables were compared to measured values and a sensitivity analysis was performed on the sources.
by Megan Elizabeth Burke.
M. Eng.
Migliavacca, Alencar. "Balanço de massa, energia e exergia na produção intensiva de frangos de corte." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3150/tde-06122017-090731/.
Full textBrazilian production of broilers has been highlighted with the implantation of the integrated production system, which improved the efficiency and quality in animal protein conversion. However, due to the rapid technological evolution with the increasing energy demand and the diversification of production systems in different microclimates, elucidating mass and energy conversion processes has become a challenging task regarding this production system. Constantly, researchers, producers and agribusiness look for more profitable processes, reducing the labour demand and environmental impact. However, an integrated evaluation of the productive system of broilers, considering the quantitative, energy and environmental aspects has never been carried out. Thus, this study aims at promoting a detailed mass and energy balance and to evaluate the quality of the energy conversions in the productive process of broilers by means of exergy analysis. With the survey of inputs, products and direct wastes, linked to the production cycle, the mass flow rates for the different processes of the cycle were quantified and a complete diagnosis of the quantity and quality energetic involved was obtained applying the exergy evaluation. Considering the scenario adopted, in mass terms, the greatest demands identified for the inputs were water (69.2%) and feed (24.9%). At the exit of the process, the greenhouse gases/dust extracted through ventilation (39.4%), the firewood combustion gases (25.6%) and the litter poultry generated (14.2%) are the main outputs. The broilers mass was quantified in 20%. The relation between water and feed consumption has shown to be the temperature. Regarding energy, the largest contribution identified for the inputs was feed (77.7%) followed by the absorbent (9.7%) and firewood (9.6%). At the exit of the process lead the energy associated with the broilers (33.2%) and the poultry litter generated (32.1%). The energy performance obtained for conventional shed was 27%. The processes of the largest exergy destroyed within the productive cycle are the litter poultry converted from excreta (51.5% in conventional and 48.2% in air conditioning) and the combustion of wood for heating (21.9% in conventional and 20.5% in air conditioning). In addition, the second law performance for the cycle was estimated in about 26%. The energy and exergy production index was introduced allowing for the comparison among different systems. As the main residue, the litter poultry generated in the cycle when reused as an input for heating the aviary itself in the form of briquettes, can increase these efficiencies. The use of LPG is more environmentally friendly compared to wood, considering the average demands for the too forms of heating, due to the direct form of heat transfer to the broilers. It is advisable, on hot days, to raise the air speed using the evaporative cooling only in cases of high ambient temperature, as the introduction of water raises the exergy dissipated in the cycle.
Laukkanen, Mikko. "Project Solaris - Mass and balance analysis tool for a solar powered UAV." Thesis, Mälardalen University, School of Innovation, Design and Engineering, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-7449.
Full textLessard, Charlotte. "Mass Balance Model of Mercury for the St. Lawrence River, Cornwall, Ontario." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/22862.
Full textHart, John 1969. "Mass balance model and field calibration for phosphorus removal from municipal wastewaters." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23368.
Full textDessau Inc. of Laval, McGill University and Ecole Polytechnique were contracted by the Ministry of the Environment and Fauna of Quebec to perform an evaluation of chemical P-removal from Quebec municipal wastewaters and the optimization of existing processes. Part of this evaluation and optimization involved clarifying the mechanisms and interactions during chemical P-removal. Many key models from literature were reviewed, but were not entirely adequate.
A static steady-state P-removal model was therefore developed, accounting for the reactions and removals of soluble and particulate forms of orthophosphate and polyphosphate/organic phosphorus. The model traces the path of each P-fraction throughout the chemical removal process, accounting for P-precipitation and adsorption, as well as reductions of TSS and BOD$ sb5.$ Computer programs were constructed for the model, with specific programs written for primary treatment, activated sludge, biofiltration and facultative aerated lagoons.
Samples were gathered at 11 WTPs during June-July 1994; these field data were used to calibrate the computer programs. Computer program output generally agreed with the field data to within 10%. Several of the WTPs sampled obtained a total-P removal of approximately 90% with metal dosed:P molar ratios often below 1.
Chin, Chi-pang Henry, and 錢志鵬. "Receptor modelling of particulates pollution in Hong Kong by chemical mass balance." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31253696.
Full textRye, Cameron James. "Spatially distributed modelling of regional glacier mass balance : a Svalbard case study." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609569.
Full textDavid, Höglin. "Regional and Local Factors Influencing the Mass Balance of the Scandinavian Glaciers." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-311152.
Full textEnligt klimatmodeller kommer en ökning av växthusgaser i atmosfären leda till en ökning av temperaturen på jorden, den ökningen kommer främst att ske på höga latituder. Glaciärer är bra indikation på förändrat klimat på grund av deras korta responstid när klimatet ändrar sig. För tillfället finns det ca 1900 glaciärer utspridda i de Skandinaviska bergen. Eftersom Skandinavien är så avlångt är det en skillnad i meterologiska och klimatiska förhållanden, både i en nord-syd riktning men även i en öst-väst riktning med kontinentala glaciärer i öst och mer marina i väst. Klimat och glaciärdata för 13 olika glaciärer i Skandinavien, 5 från Sverige och 8 ifrån Norge har samlats in och en statistisk analys, principle component analysis (PCA) har gjorts för att se vad som påverkar massbalansen för glaciärerna. De klimat parametrar som har undersökts är Nordatlantsika oscillationen (NAO), Arktiska oscillationen (AO) och solfläckar tillsammans med massbalans, equilibrium line altitude (ELA) och area för glaciärerna. Tre grupperingar har hittats som kan kopplas till olika klimatvariabler och PCA visar extremår för NAO och AO samt en glaciär som har den största arean. PCA analysen visade att alla variabler korrelerade till NAO och AO med omkring 40 % och vi kan dra slutsatsen att det finns en drivande regional och lokal kraft inom vårat dataset där NAO och AO är viktigast för massbalansen.
Chin, Chi-pang Henry. "Receptor modelling of particulates pollution in Hong Kong by chemical mass balance /." Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B18736063.
Full textCimino, Joseph A. "Empirical mass balance calibration of analytical hydrograph separation techniques using electrical conductivity." [Tampa, Fla.] : University of South Florida, 2003. http://purl.fcla.edu/fcla/etd/SFE0000213.
Full textPIVETTA, TOMMASO FERRUCCIO MARIA. "Gravimetry for monitoring water mass movements in karstic areas." Doctoral thesis, Università degli Studi di Trieste, 2021. http://hdl.handle.net/11368/2988158.
Full textKarst aquifers represent a significant source of water for about 1/4 of the world’s population. The water circulation in karst occurs mostly underground and it is mainly controlled by alternation of small conduits and large voids present in the rock massif. Such intricate void distribution combined with an irregular recharge provided by the rain results in fast and complex water flows with temporary accumulation of huge water volumes in the voids. The knowledge of the dynamics of such system is usually limited to the areas where a direct access to the vadose zone through speleological exploration is possible. Given the importance of such aquifers and their vulnerability it is important to have a detailed picture of the water dynamics and of the underground water paths. Gravimetry offers a valid complement to classical hydrologic measurements in order to monitor the recharge process. In this thesis, I show an innovative integration of gravimetric and hydrologic observations to constrain a hydrodynamic model of the Škocjan cave system (Slovenia). The Škocjan caves hydrology is mostly governed by the allogenic contribution of the Reka River, which during flood event causes the accumulation of several millions of m3 of water in the cave system for few hours. In 2018 I installed a continuous recording gravimeter nearby Škocjan which allowed the detection of several gravity transients related to the local hydrologic contribution. Gravity observations are sensitive to several other contributions apart the hydrology, such as Earth and marine tides, atmospheric mass redistribution, water mass variations in oceans. All these phenomena superpose their effects and should be carefully evaluated and removed before unveiling the local hydrology contribution. Before discussing the hydrologic gravity signals, the thesis illustrates the efforts in modelling and removing all the non-hydrologic related gravity contributions. The study area is close to the Adriatic Sea, hence global models of tidal and non-tidal ocean (NTO) gravity effects could be inadequate for the correction. I prove that while tidal models are sufficiently accurate to remove the marine tidal influence a dedicated correction of the NTO is required. This was fulfilled by modelling the gravity variations due to a 4D mass model of the NTO constrained by tide gauge observations. The gravity residuals, obtained after reducing the observations for all the non-hydrologic effects, revealed anomalies correlated to the Reka flooding; the transients lasted for 12-24 hours with amplitudes in the range 10-450 nm/s2. I focused my analysis on a large flood event in February 2019 that caused water level variations >90 m inside the caves and gravity variations >400 nm/s2. The gravity and the hydrologic data were used to constrain a hydraulic model of the cave system which approximated the cavity through a series of interconnected conduits with rectangular cross-section. I fitted hydrologic and gravity observations obtaining a 4D model of the water mass variations in the cave system; the model revealed that >3 106 m3 of water were temporary accumulated during the peak’s flood. The inclusion of gravity observations improves water mass budget of the caves, which previously were based relying only on hydrological observations. Finally, the gravity data allowed to draw some general conclusions on the detectability of water storage variations in karst through gravimetry. I assessed the noise level of the Škocjan gravimeter which is about 10 nm/s2 in the diurnal spectral band and which can be taken as representative of the noise level of a typical spring based gravimeter. Relying on realistic water level variations I estimated the expected gravity signals on surface due to temporary water accumulation in other caves of the Classical Karst. For all the considered caves the gravity signal is above the noise threshold, suggesting that a remote monitoring of the storage variations is feasible.
Eriksson, Rehn Ida. "Mass balance and local characteristics of three glaciers in southern Norway, between 1980 and 2018 : An analysis of the mass balance and the local characteristics of Ålfotbreen, Storbreen and Gråsubreen." Thesis, Stockholms universitet, Institutionen för naturgeografi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-184671.
Full textDahl, Magnus. "Appropriate Modelling Complexity: An Application to Mass Balance Modelling of Lake Vänern, Sweden." Doctoral thesis, Uppsala University, Department of Earth Sciences, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4239.
Full textThis work is about finding an appropriate modelling complexity for a mass-balance model for phosphorus in Lake Vänern, Sweden. A statistical analysis of 30 years of water quality data shows that epilimnion and hypolimnion have different water quality and should be treated separately in a model. Further vertical division is not motivated. Horizontally, the lake should be divided into the two main basins Värmlandssjön and Dalbosjön. Shallow near shore ares, bays and areas close to point sources have to be considered as specific sub-basins if they are to be modelled correctly.
These results leads to the use of a model based on ordinary differential equations. The model applied is named LEEDS (Lake Eutrophication Effect Dose Sensitivity) and considers phosphorus and suspended particles. Several modifications were made for the application of the model to Lake Vänern. The two major ones are a revision of the equations governing the outflow of phosphorus and suspended particle through the outflow river, and the inclusion of chemical oxygen demand (COD) into the model, in order to model emissions from pulp and paper mills. The model has also been modified to handle several sub-basins.
The LEEDS model has been compared to three other eutrophication models applied to Lake Vänern. Two were simple models developed as parts of catchment area models and the third was a lake model with higher resolution than the LEEDS model. The models showed a good fit to calibration and validation data, and were compared in two nutrient emission scenarios and a scenario with increased temperature, corresponding to the green house effect.
Karlsson, Olof Magnus. "Predicting Ecosystem Response from Pollution in Baltic Archipelago areas using Mass-balance Modelling." Doctoral thesis, Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-144120.
Full textFelaktigt tryckt som Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 736
Cao, Qianwen. "Mass Balance of Major, Minor and Trace Elements During AFBC Combustion of Fuels." TopSCHOLAR®, 1997. http://digitalcommons.wku.edu/theses/899.
Full textClendon, Penelope Catherine. "Summertime surface mass balance and atmospheric processes on the McMurdo Ice Shelf, Antarctica." Thesis, University of Canterbury. Geography, 2009. http://hdl.handle.net/10092/2630.
Full textBoström, Björn. "Achieving carbon isotope mass balance in Northern forest soils, soil respiration and fungi /." Örebro : Department of Natural Sciences, Örebro University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-2101.
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