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Avställning av luftad damm : Nedbrytning av organiskt material med hänsyn till årstidsvariationSelöfalk, Sara January 2006 (has links)
Som följd av utökat tillstånd för produktion vid Billerud AB:s pappersbruk, Gruvön, i Grums har bruket byggt en ny avloppsreningsanläggning med flerstegsrening. Den tidigare reningsanläggningen, en luftad damm belägen i Ålviken i anslutning till Vänern, kommer därmed att stängas. Syftet med föreliggande rapport har därför varit att undersöka huruvida dammen behöver hållas aktiv genom luftning en tid framöver för att gynna nedbrytning av organiskt material samt undvika uppkomsten av illaluktande gaser. Nedbrytningshastigheten har studerats med hjälp av glödförlust, COD-tester och alkalinitet. COD-testerna genomfördes enligt ampullmetoden Hach-Lange i miljölabbet vid Gruvöns bruk. Alkaliniteten har bestämts genom titrering av svavelsyra. Försöken gjordes under en tidsperiod på tre månader. Slam hämtades från tre provpunkter i dammen och delades upp i en anläggning för aerobisk nedbrytning samt för anaerobisk nedbrytning. De resultat som framkom vid undersökningarna var att nedbrytningen i samtliga provpunkter sker långsamt. Genom linjärregression har tiden för nedbrytningen beräknats. För att bryta ner det organiska materialet i dammen skulle det, enligt den här metoden, ta ca 3 år för den anaeroba processen samt 15 år för den aeroba processen. Den stora tidsskillnaden här emellan beror till stor del på var i dammen slammet är upphämtat. Att stänga av luftarna i dammen efter att avloppsvattenflödet stängts av innebär energimässiga och ekonomiska vinster. Den anaeroba nedbrytningen som följer därefter kommer då att skapa illaluktande gaser såsom svavelväte och metangas. / As a result of increased permission to produce paper and paper pulp at the paper mill Gruvön AB in Grums the mill has built a multiple step waste water treatment construction. The previous treat construction was an aerated lagoon located in Vänern which now will be shut down. The aim of this report is to examine whether this aerated lagoon needs to be aereated to keep the decomposition of the organic material and/or to avoid origin of odours. The decomposition rate is studied by loss on ignition, COD-tests and alcalinity. The COD-tests was performed in the environmental lab at Gruvön by the ampoule method according to Hach-Lange. The alcalinity was determined by titration with sulfuric acid. The experiments were performed during a period of three months. Sludge was collected from three test points from the lagoon. The sludge was then separated into one construction to measure the aerobic decomposition and one to measure the anaerobic decomposition. The results show that the decomposition rate is low. The decomposition rate has been evaluated by linear regression. This method indicates that it would take about three years for the anaerobic process and about 15 years for the aerobic process to degrade all the organic compound. The difference in time between the two processes is probably dependent on for example the test points localization in the lagoon. To turn off the aerators of the lagoon could save energy and gain economical profits. The anaerobic decomposition that begins after closing down the aerators could result in creation of chemical odours such as hydrogen sulphide and methane.
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Kartläggning och nedbrytning av komplexbildare i ett integrerat kartongbruk / Mapping and degradation of chelating agents in an integrated board millLöfgren, Lina, Olsson, Robert January 2006 (has links)
Skoghalls Bruk fick i juni 2005 tillstånd av miljödomstolen att öka kartongproduktionen från 665 000 till 800 000 ton kartong per år. Villkoren för tillståndet var att under en prövotidsperiod bl.a. utreda möjligheten att minska utsläpp till omkringliggande vatten. Syftet med examensarbetet var att kartlägga Skoghalls Bruks avloppssystem med avseende på komplexbildarna EDTA (etylendiamintetraättiksyra) och DTPA (dietylentriaminpentaättiksyra), kväve samt fosfor. Dessutom genomfördes nedbrytningsförsök i luftade dammar i laboratorieskala. För att få en klarare bild av nedbrytningen i Skoghalls Bruks luftade damm gjordes även en molekylviktsfraktionering på inkommande och utgående avloppsvatten. Komplexbildare används inom pappers- och massaindustrin för sin förmåga att binda till sig metalljoner som kan vara skadliga i processen. Metalljoner katalyserar nedbrytningen av väteperoxid i blekningen och påskyndar bildandet av aldehyder i kartongen vilket kan leda till lukt- och smakpåverkan. EDTA och DTPA anses vara stabila ämnen, vilket innebär att de är biologiskt svårnedbrytbara. Under den litteraturstudie som genomfördes fanns motsägande uppgifter angående nedbrytningen av komplexbildare, där vissa menade att de genomgår biologisk nedbrytning, men att det sker mycket långsamt. Andra påstod att komplexbildare inte bryts ner överhuvudtaget. Komplexbildare kan elimineras genom fotokemisk oxidativ nedbrytning. Då EDTA och DTPA bildar komplex med Fe3+ blir de fotokemiskt labila och oxideras till mindre föreningar vid belysning med ultraviolett ljus. Sammanfattningsvis gav litteraturstudien att det mest effektiva sättet att minska komplexbildare i avloppsvatten innan det släpps till recipienten är att UV-bestråla vid optimala förhållanden, dvs. rätt pH och eventuellt tillsats av Fe3+ om det behövs. Provtagning av avloppsvatten i Skoghalls Bruks reningsanläggning gjordes under 6 veckor för att kartlägga utsläppen och de olika delströmmarnas bidrag. Nedbrytningsförsök genomfördes i två luftade dammar i laboratorieskala. För att studera temperaturens inverkan konstruerades en sommar- och en vinterdamm med temperaturerna 27 respektive 16°C. Efter referensförsöket, som gjordes för att se eventuella skillnader mellan försöken, undersöktes inverkan av ultraviolett ljus på nedbrytningen av komplexbildare. Sedan tillsattes Fe3+ i form av järnklorid i ett försök att öka den fotokemiska nedbrytningen. Alla försök pågick under två veckor vardera. I syfte att undersöka partikelstorleksfördelningen före och efter nedbrytning i Skoghalls Bruks luftade damm gjordes en molekylviktsfraktionering. Inkommande och utgående avloppsvatten från dammen ultrafiltrerades och analyserades med avseende på COD (Chemical Oxygen Demand), komplexbildare, kväve och fosfor. Kartläggningen visade att EDTA bröts ner effektivt i reningsanläggningen medan nedbrytningen av DTPA var obetydlig. EDTA reducerades med 88 % över den luftade dammen. Avlopp från kartongmaskinerna samt CTMP-fabriken var de avlopp som innehöll mest EDTA. Största mängden DTPA återfanns i blekerifiltratet och i KM 8:s avlopp. Skoghalls Bruk släppte ut komplexbildare motsvarande 0,188 kg/ton kartong, i form av 100 % syra i obunden form, under karteringsperioden vilket var klart lägre än gränsvärdet som är 1,6 kg 100 % syra/ton kartong. Kväve reducerades med 67 % över den luftade dammen. Det nuvarande gränsvärdet för kväveutsläpp till recipient är 500 kg/dygn, men ett av målen med prövotidsutredningen är att minska utsläppen till 300 kg/dygn. Enligt resultaten från karteringsperioden var kväveutsläppet 204 kg/dygn vilket uppfyller målet för prövotidsutredningen. Av det totala kväveutsläppet kom 39 kg/dygn från komplexbildare. Utsläppet av kväve från mixeriavloppet var 56 kg/dygn till recipient vilket var klart högre än förväntat. Den totala fosforreduceringen över reningsanläggningen var 78 %. Utsläppet av fosfor till recipient var 19 kg/dygn vilket är klart lägre än gränsvärdet som är 50 kg/dygn. På grund av komplexbildaranalysens mätosäkerhet var det svårt att få entydiga resultat från laboratorieförsöken. Det fastställdes dock att DTPA var svårare att bryta ner än EDTA och att järntillsats i kombination med ultraviolett ljus gav en positiv effekt på nedbrytningen av båda komplexbildarna. Även nedbrytningen av COD, kväve och fosfor ökade vid järntillsats. Att DTPA är svårare att bryta ner än EDTA framkom även av resultaten från molekylviktsfraktioneringen. Det visade sig också att EDTA och DTPA inte är helt vattenlösliga utan kan binda till fast material. Största delen av komplexbildarna fanns dock i fraktionen med partiklar med molekylvikt mindre än 1 kDa. Kväve och fosfor fanns i de låg- och högmolekylära fraktionerna. / In June of 2005 Skoghall Mill got permission from the Environmental Court to increase their production of board from 665 000 tons to 800 000 tons per year. The condition for the permission was to, during a trial period, investigate the possibility to decrease the emissions to the surrounding water. The purpose of this master thesis is to do a mapping of Skoghall Mill’s waste water treatment system regarding the chelating agents EDTA (ethylenediaminetetraacetic acid) and DTPA (diethylenetriaminepentaacetic acid), nitrogen and phosphor. Also degradation-trials were made with aerated lagoons in laboratory-scale. To get a more complete view of the degradation in Skoghalls Mills aerated lagoon a molecular weight fractionation of the incoming and the outgoing water was made. Chelating agents are used in the pulp- and paper industry due to its ability to bind metal-ions which are hazardous for the process. The metal-ions catalyze the decomposition of hydrogen peroxide in the bleaching process and the forming of aldehydes in the board which can lead to problems with taste and odour. EDTA and DTPA are regarded to be very stable, which means that they are hard to degrade biologically. There was contradictory information about the degradation of chelating agents during the literature survey. Some say that chelating agents are degraded biologically but very slowly. Others say that they don’t degrade at all. Chelating agents can be eliminated through photochemical oxidative degradation. When EDTA and DTPA form complexes with Fe3+ they become photolabile and oxidize to smaller compounds at illumination with ultraviolet light. To sum up the literature survey, the most efficient way to reduce chelating agents in sewage water before discharge to receiving waters, is UV treatment at optimal conditions i.e., at the right pH and with addition of Fe3+ if necessary. The sampling of the waste water in Skoghalls waste water treatment plant was made during 6 weeks to map the emissions and the contribution of the different sub-streams. The degradation-trials were made in two aerated lagoons in laboratory-scale. To study the influence of temperature a summer- and a winter-lagoon were made and the temperatures were sat to, respectively, 27 and 16°C. After the reference-trial, which was made to determine possible differences between the trials, the influence of ultraviolet light on degradation of chelating agents were investigated. In an attempt to enhance the photochemical degradation, Fe3+ in the form of ferric chloride was then added. All trials went on for two weeks each. In order to investigate the particle size distribution, before and after degradation in Skoghall Mill’s aerated lagoon, a molecule weight fractionation was made. Incoming and outgoing sewage water from the lagoon was ultra-filtrated and analyzed regarding COD (Chemical Oxygen Demand), chelating agents, nitrogen and phosphor. The mapping showed that EDTA was efficiently degraded in the waste water treatment plant, while degradation of DTPA was insignificant. EDTA was reduced by 88 % trough the aerated lagoon. Waste water from the board machines and the CTMP-plant contained the largest amount EDTA. DTPA was recovered mostly in the bleaching filtrate and KM 8’s waste water. The emission of chelating agents, counted as acid, from Skoghall Mill during the period of the mapping was 0,188 kg/ton board which is well below the emission limit value of 1,6 kg/ton board. Nitrogen was reduced by 67 % through the aerated lagoon. The present emission limit value for nitrogen is 500 kg/day. According to the results from the period of the mapping the emission of nitrogen was 204 kg/day which is well below the emission limit value. The contribution of chelating agents to the nitrogen emission was 39 kg/day. 56 kg nitrogen /day were recovered in the waste water from the causticizing area, which is remarkably higher than expected. The total reduction of phosphor through the waste water treatment plant was 78 %. The emission of phosphor to receiving waters was 19 kg/day which is well below the emission limit value of 50 kg/day. Due to the insecurity in measurement of chelating agents, it was difficult to retain unambiguous results from the laboratory-trials. However it was determined that DTPA was more difficult to degrade than EDTA and that a combination of ultraviolet light and addition of ferric iron had a favourable effect on the degradation of both chelating agents. Also the degradation of COD, nitrogen and phosphor increased when ferric iron was added. The fact that DTPA are more difficult to degrade than EDTA was also stated in molecular weight fractionation. It was also shown that EDTA and DTPA weren’t totally water-soluble but can bind to solid material. The largest amount of chelating agents was recovered in the fraction with particles whose molecular weight is less than 1 kDa. Nitrogen and phosphor were recovered in the low- and high-molecular fractions.
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Comparative assessment of large dam projects a challenge for multi-criteria decision analysisPetersson, Elke Unknown Date (has links)
Techn. Univ., Diss., 2006--Darmstadt
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Acute cytokine responses to inhaled swine confinement building dust /Wang, Zhiping, January 1900 (has links) (PDF)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 5 uppsatser.
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Numerical analysis and design criteria of embankments on floating piles /Satibi, Syawal. January 2009 (has links)
Zugl.: Stuttgart, University, Diss., 2009.
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CFD-baserad analys av Rusfors-dammen före och efter ombyggnad / CFD-based analysis of Rusfors dam before and after rebuildingXU, XUSHENG January 2016 (has links)
Hydraulic model studies of the Rusfors dam were previously made, the purpose of which was to examine the rebuilding solution for safe discharge of its design flood. In this work, two-phases computational fluid dynamics simulations were conducted to provide essential insights that help better comprehend the model test results. The hydraulic characteristics investigated in numerical modelling included the velocity profile, flow pattern profile and energy dissipation capacity. Through analysis of the results obtained from numerical modelling and hydraulic model tests, the modified dam was found to have better energy dissipation capacity and sediment cleaning ability than the previous dam. / Hydrauliska modellstudier av Rusfors dammen tidigare gjort, vars syfte var att undersöka återuppbyggnaden lösning för säker urladdning av dess utformning översvämning. I detta arbete har två faser computational vätska dynamik simuleringar genomförts för att ge viktiga insikter som hjälper bättre begripa de modelltestresultaten. De aspekter som undersöks i numerisk modellering inkluderar hastighetsprofilen , strömningsmönstret profil och energiförbrukningskapacitet. Genom analys av resultaten från numerisk modellering och hydrauliska modellförsök, var den modifierade dammen visade sig ha bättre energiförbrukningskapacitet och sediment rengöringsförmåga än tidigare dammen.
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How do consumers get engaged in a brand community? : The case of Estrella Damm.Cruz, Dana, Aulestia, Emma January 2021 (has links)
Background: Looking at many different studies, it’s known that the topics mentioned before are well researched. However, there are not many cases of brand community and customer engagement like the one with Estrella Damm. That’s why the authors wanted to work on the combination of all of them with the use of the company Estrella Damm, as they are highly involved in its community and it has made a big change in the last few years. Going from a brand of living life to a brand that generates consciousness about the Mediterranean Sea. Purpose: The purpose of the following research is to demonstrate that by putting into a side the brand's product the researchers can feel engaged through the actions they have. The objective is to answer the question; “How do consumers get engaged in a brand community? The case of Estrella Damm”. Method: For this qualitative study, case study and autoethnography methods were used to analyze in-depth the research question due to the deep knowledge of how this engages since the researchers are part of its brand community. These methods are the most appropriate since the analyzed brand is focused on creating awareness of the Mediterranean contamination, and the researchers know first-hand the engagement with the brand. Thus, a case study of this company, and with the support of the autoethnography of the authors, permit to develop as properly as possible study. Conclusion: Consumers get engaged in a brand community through different actions the company makes. In this study, the main factor of being engaged involves the company showing to the consumer that it is not only focused on its product/service, but is using its influence and power to improve social and environmental welfare, and thus, the company gets an engaged and committed consumer in its community.
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"Det har ju alltid varit en damm här" : En utredning av MP 5a§ påverkan på tillstånd för dammanläggningar / "It´s always been a dam here" : An investigation of the effects of MP 5a§ on dam legislationGustafsson, Nora January 2021 (has links)
No description available.
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Strömaterials påverkan på mängden luftburna partiklar i häststallJohansson, Johanna January 2020 (has links)
No description available.
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Transport of mineral dust into the Arctic : Evaluation of two reanalysis datasets of atmospheric compositionBöö, Sebastian January 2023 (has links)
The main purpose of this thesis is to examine the mineral dust aerosol transport into the Arctic. Two three-dimensional reanalysis datasets of atmospheric composition, the Copernicus Atmosphere Monitoring Service reanalysis (CAMSRA) and the Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2), are analyzed with regard to dust transport into the Arctic. The reanalyses agree on that the largest mass transport of dust into the Arctic occurs across western Russia during spring and early summer, although large dust transport events can occur across other geographical areas during all seasons. In several aspects, the reanalyses show substantial differences. The transport in CAMSRA is considerably smaller, more concentrated and occurs at lower altitudes. Furthermore, the transport in CAMSRA is to a larger extent than MERRA-2 driven by well-defined events of dust transport in space and time. The reanalysis data are compared with surface measurements of dust in the Arctic and dust extinction satellite retrievals from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP). The comparison indicates that CAMSRA underestimates the dust transport into the Arctic and that MERRA- 2 likely overestimates it. The discrepancy between CAMSRA and MERRA-2 can in part be explained by the assimilation process where too little dust is assimilated in CAMSRA while MERRA-2 overestimates the production of light particles, causing an excessive transport, and the assimilation process further increases the dust concentration in remote areas. Despite the clear differences between the reanalyses, this study provides new insights into the spatio-temporal distribution of the dust transport into the Arctic and the transported mass is estimated to be within the range 1.5–31 Tg yr-1. The thesis also briefly examines the aerosol transport of all five aerosol species carried by the reanalyses, that in addition to dust are black carbon, organic matter, sea-salt and sulfate. The annual aerosol mass transport to the Arctic in CAMSRA and MERRA-2 are 24 Tg and 50 Tg respectively. The reanalyses show substantial differences regarding the proportions of the different aerosol types — emphasizing that it is crucial that the aerosol module manages to simulate the correct aerosol mass fractions, as the assimilation of AOD alone cannot change the proportions between the aerosols.
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