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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Absorption of CO2 : - by Ammonia / Absorption of CO2 : - by Ammonia

Sjöstrand, Filip, Yazdi, Reza January 2009 (has links)
In this diploma work, the absorption of CO2 in different liquid solutions was studied by gas absorption in a randomly packed column. To characterize the absorption a few experiments with SO2 absorption were made.The report has resulted due to the large amounts of carbon dioxide released into the atmosphere, mainly from fossil-fired power plants. To reduce these emissions, carbon dioxide can be separated from flue gas by different techniques such as CO2 absorption with ammonia. The work consists of a theoretical and a laboratory part of measurements and calculations. In the experimental part a system of absorption and associated test equipment was constructed. Different liquid solutions of pure water, potassium carbonate solution and ammonia in various concentrations were used to catch carbon dioxide by countercurrent absorption. Also SO2 was absorbed in the potassium carbonate solution to determine the gas film constant. The absorption efficiency of CO2 ranged from a few percent in the experiment with water to up to 7% with potassium carbonate solution. The CO2 absorption of ammonia varied with concentration and gave a separation of between 12 and 94%. Ammonia tests were made at both 10 and 20 °C. In general, a higher CO2-capture at 20 °C was obtained as confirmed by theory. / I detta examensarbete har absorptionseffektivitet av CO2 hos olika vätskelösningar undersökts genom gasabsorption i en slumpmässigt packad kolonn. För att karakterisera absorptionen absorberades även SO2 i några experiment. Rapporten är utförd med anledning av de stora mängder koldioxid som släpps ut i atmosfären, främst från fossileldade kraftverk. För att minska dessa utsläpp kan koldioxiden avskiljas från rökgaserna genom olika tekniker t.ex. genom CO2-absorption med ammoniak. Arbetet består av en teoridel och en laborativ del med mätningar och beräkningar. I den experimentella delen konstruerades ett system med en absorptionskolonn och tillhörande mätutrustning. Olika vätskelösningar bestående av rent vatten, kaliumkarbonatlösning och ammoniak i olika koncentrationer användes till att ta upp koldioxid genom motströms absorption. Även SO2 absorberades i kaliumkarbonatlösning för att bestämma gasfilmkonstanten. Absorptionsgraden av CO2 varierade från några få procent i försöket med vatten upp till 7 % med kaliumkarbonatlösningen. CO2-absorptionen av ammoniak varierade med koncentrationen och gav en avskiljning på mellan 12 och 94 %. Ammoniakförsöken gjordes med både vid 10 och 20 °C. Generellt erhölls en bättre CO2-avskiljning vid 20°C, vilket bekräftas av teorin.
12

Absorption of CO<sub>2 </sub> : - by Ammonia / Absorption of CO<sub>2 </sub> : - by Ammonia

Sjöstrand, Filip, Yazdi, Reza January 2009 (has links)
<p>In this diploma work, the absorption of CO<sub>2 </sub>in different liquid solutions was studied by gas absorption in a randomly packed column. To characterize the absorption a few experiments with SO<sub>2</sub> absorption were made.The report has resulted due to the large amounts of carbon dioxide released into the atmosphere, mainly from fossil-fired power plants. To reduce these emissions, carbon dioxide can be separated from flue gas by different techniques such as CO<sub>2</sub> absorption with ammonia. The work consists of a theoretical and a laboratory part of measurements and calculations. In the experimental part a system of absorption and associated test equipment was constructed. Different liquid solutions of pure water, potassium carbonate solution and ammonia in various concentrations were used to catch carbon dioxide by countercurrent absorption. Also SO<sub>2</sub> was absorbed in the potassium carbonate solution to determine the gas film constant. The absorption efficiency of CO<sub>2</sub> ranged from a few percent in the experiment with water to up to 7% with potassium carbonate solution. The CO<sub>2</sub> absorption of ammonia varied with concentration and gave a separation of between 12 and 94%. Ammonia tests were made at both 10 and 20 °C. In general, a higher CO<sub>2</sub>-capture at 20 °C was obtained as confirmed by theory.</p> / <p>I detta examensarbete har absorptionseffektivitet av CO<sub>2</sub> hos olika vätskelösningar undersökts genom gasabsorption i en slumpmässigt packad kolonn. För att karakterisera absorptionen absorberades även SO<sub>2</sub> i några experiment.</p><p>Rapporten är utförd med anledning av de stora mängder koldioxid som släpps ut i atmosfären, främst från fossileldade kraftverk. För att minska dessa utsläpp kan koldioxiden avskiljas från rökgaserna genom olika tekniker t.ex. genom CO<sub>2</sub>-absorption med ammoniak.</p><p>Arbetet består av en teoridel och en laborativ del med mätningar och beräkningar. I den experimentella delen konstruerades ett system med en absorptionskolonn och tillhörande mätutrustning. Olika vätskelösningar bestående av rent vatten, kaliumkarbonatlösning och ammoniak i olika koncentrationer användes till att ta upp koldioxid genom motströms absorption. Även SO<sub>2</sub> absorberades i kaliumkarbonatlösning för att bestämma gasfilmkonstanten. Absorptionsgraden av CO<sub>2</sub> varierade från några få procent i försöket med vatten upp till 7 % med kaliumkarbonatlösningen. CO<sub>2</sub>-absorptionen av ammoniak varierade med koncentrationen och gav en avskiljning på mellan 12 och 94 %. Ammoniakförsöken gjordes med både vid 10 och 20 °C. Generellt erhölls en bättre CO<sub>2</sub>-avskiljning vid 20°C, vilket bekräftas av teorin.</p>
13

Estudo de uma coluna de absor??o recheada para desidrata??o do g?s natural utilizando microemuls?o como absorvente

N?brega, Geraldine Ang?lica Silva da 11 October 2007 (has links)
Made available in DSpace on 2014-12-17T15:01:44Z (GMT). No. of bitstreams: 1 GeraldineASN.pdf: 1064448 bytes, checksum: e84e59e89db44381c1e32c94012cfe01 (MD5) Previous issue date: 2007-10-11 / During natural gas processing, water removal is considered as a fundamental step in that combination of hydrocarbons and water favors the formation of hydrates. The gas produced in the Potiguar Basin (Brazil) presents high water content (approximately 15000 ppm) and its dehydration is achieved via absorption and adsorption operations. This process is carried out at the Gas Treatment Unit (GTU) in Guamar? (GMR), in the State of Rio Grande do Norte. However, it is a costly process, which does not provide satisfactory results when water contents as low as 0.5 ppm are required as the exit of the GTU. In view of this, microemulsions research is regarded as an alternative to natural gas dehydration activities. Microemulsions can be used as desiccant fluids because of their unique proprieties, namely solubilization enhancement, reduction in interfacial tensions and large interfacial area between continuous and dispersed phases. These are actually important parameters to ensure the efficiency of an absorption column. In this work, the formulation of the desiccant fluid was determined via phases diagram construction, employing there nonionic surfactants (RDG 60, UNTL L60 and AMD 60) and a nonpolar fluid provided by Petrobras GMR (Brazil) typically comprising low-molecular weight liquid hydrocarbons ( a solvent commonly know as aguarr?s ). From the array of phases diagrams built, four representative formulations have been selected for providing better results: 30% RDG 60-70% aguarr?s; 15% RDG 60-15% AMD 60-70% aguarr?s, 30% UNTL L60-70% aguarr?s, 15% UNTL L60-15% AMD 60-70% aguarr?s. Since commercial natural gas is already processed, and therefore dehydrated, it was necessary to moister some sample prior to all assays. It was then allowed to cool down to 13?C and interacted with wet 8-12 mesh 4A molecular sieve, thus enabling the generation of gas samples with water content (approximately 15000 ppm). The determination of the equilibrium curves was performed based on the dynamic method, which stagnated liquid phase and gas phase at a flow rate of 200 mL min-1. The hydrodynamic study was done with the aim of established the pressure drop and dynamic liquid hold-up. This investigation allowed are to set the working flow rates at 840 mL min-1 for the gas phase and 600 mLmin-1 for the liquid phase. The mass transfer study indicated that the system formed by UNTL L60- turpentine-natural gas the highest value of NUT / No processamento do g?s natural, a remo??o da ?gua representa uma etapa fundamental, pois a combina??o de hidrocarboneto e ?gua propicia a forma??o de hidratos. O g?s produzido na Bacia Potiguar apresenta altos teores de ?gua (aproximadamente de 15000 ppmv) e para sua desidrata??o s?o utilizados processos de absor??o e adsor??o. Estes processos s?o utilizados na Unidade de Tratamento de G?s (UTG) em Guamar? (GMR), RN. S?o considerados onerosos e n?o oferecem bons resultados quando se deseja obter um teor m?ximo de 0,5 ppm de ?gua na jusante da UTG. Dentro deste contexto, a pesquisa na ?rea das microemuls?es surge como alternativa para que sua utiliza??o como l?quido dessecante em um processo de absor??o desidrate o g?s natural. As microemuls?es foram escolhidas por possu?rem alta capacidade de solubiliza??o, redu??o da tens?o interfacial e grande ?rea interfacial entre as fases cont?nua e dispersa, par?metros importantes para garantir a efici?ncia de uma coluna de absor??o. Para a formula??o do l?quido dessecante foram constru?dos diagramas de fases com tr?s tensoativos n?o-i?nicos (RDG 60, UNTL L60 e AMD 60), e aguarr?s (Petrobras-GMR). Diante dos diagramas constru?dos foram utilizados quatro formula??es sendo elas: 30% RDG 60-70% aguarr?s; 15%RDG 60-15%AMD 60-70% aguarr?s; 30% UNTL L60-70% aguarr?s; 15%UNTL L60-15%AMD 60-70% aguarr?s. Como o g?s natural comercializado ? processado, foi necess?rio umidific?-lo, e para isto ele foi submetido a resfriamento (13?C), utilizando peneira molecular 4A de 8 a 12 mesh ?mida, e assim obter elevada concentra??o de ?gua (aproximadamente 15000 ppm). A determina??o das curvas de equil?brio foi realizada com base no m?todo din?mico, estando a fase l?quida estagnada e fase gasosa com vaz?o de 200mL/min. O estudo hidrodin?mico foi realizado para determinar a queda de press?o e determina??o do hold-up l?quido din?mico, que determinou que as vaz?es de trabalho deveriam ser 840 mL/min para a fase gasosa e 600 mL/min para a fase l?quida. O estudo da transfer?ncia de massa indicou que o sistema formado por UNTL L60-Aguarr?s-G?s Natural apresentou o maior valor de NUT. Com base nos valores calculados para o AUT dos sistemas, foi poss?vel observar que todos precisam da maior altura de coluna. Com rela??o ao coeficiente global de transfer?ncia de massa, todos os sistemas apresentaram valores pr?ximos, com exce??o do sistema UNTL L60-Aguarr?s-G?s Natural que, dentre os sistemas, ? o que necessita de uma altura maior na coluna. Dentre as quatro formula??es, os sistemas com a presen?a de AMD 60 apresentaram os maiores valores de coeficiente global de transfer?ncia e efici?ncia, o que mais uma vez comprova a maior solubiliza??o da ?gua em presen?a da mistura de tensoativos
14

Analysis Of Protein Purification By Affinity Chromatography

Sridhar, P 05 1900 (has links) (PDF)
No description available.
15

Process and techno-economic analysis of a compact CO2 capture technology / Process och tekno-ekonomisk analys av ett kompakt CO2 infångningsteknik

Salvador Palacios, Nestor January 2023 (has links)
Den stora oron för de ökade växthusutsläppen och klimatförändringas effekter har uppmuntrat utvecklingen av åtgärder för att motverka de negativa konsekvenserna. En av de tekniker som har uppmärksammats under de senaste decennierna är kolavskiljningstekniken. Men nuförtiden är kolavskiljning en teknik som är relaterad till höga kostnader där både kapital- och driftskostnaderna är höga. Därför utfördes i detta projekt ett försök att minska kostnaden genom att ersätta den absorptionspackade kolonnen med ett nytt kompakt system. I detta fall atomiserade det kompakta systemet lösningsmedlet till droppar för att öka massöverföringen av koldioxidabsorptionen. Syftet med detta projekt var att utföra en jämförande teknisk-ekonomisk utvärdering av den konventionella kemiska absorptionsprocessen med packade kolonner mot en process med ett kompakt system. En processmodell för den konventionella processen etablerades i Aspen Plus. Dessutom manipulerades den berikade lösningen i samma processmodell för att simulera den förbättrade absorptionen på grund av atomatiseringen av lösningsmedlet. Det resulterade i att implementeringen av det kompakta systemet kunde generera tekniska förbättringar som ett minskat användande av lösningsmedel och en lägre återkokningsbelastning i regenereringskolonnen. Det var dock ingen betydande minskning av den totala fångstkostnaden. I det här fallet var de främsta bidragande faktorerna till fångstkostnaden var kompressorkostnaden och det höga elpriset. Känslighetsanalysen visade dock i huvudsak att fångstkostnaden skulle kunna sänkas när elpriset är lägre. Man kan dra slutsatsen att kompakta system är en lovande teknik som skulle kunna bidra till utvecklingen av kolavskiljningstekniken. Framtida undersökningar av processdesignen krävs dock för att sänka fångstkostnaden ännu mer. / The great concern regarding the increased greenhouse emissions and the effects of the climate change has encouraged the development of solution in order to counteract the negative consequences. One of the technologies that has gained attention during the last decades has been the carbon capture technology. However, nowadays the carbon capture has been a technology that has been related to high capture costs where both capital and operational costs usually has been high. Therefore, in this project, an attempt was realized to reduce the capture cost by replacing the absorption packed column with a novel compact system. In this case, the compact system atomized the solvent into droplets in order to enhance the mass transfer of the carbon dioxide absorption. The aim of this project was to perform a comparative techno-economical evaluation of the conventional chemical absorption process with packed columns to a process with a compact system. A process model for the conventional process was established in Aspen Plus. Furthermore, the rich loading was varied in the same process model in order to simulate the enhanced absorption due to the atomization of the solvent. It resulted that the implementation of the compact system could generate technical benefits such as a reduced solvent utilization and a lower reboiler duty in the stripper column. However, there was no significant reduction regarding the total capture cost. In this case, the main contributors to the capture cost were the compressor cost and the high electricity price. Nevertheless, the sensitivity analysis showed principally that the capture cost could be reduced if the power required in the flue gas compressor can be reduced. It could be concluded that the compact system is a promising technology that could contribute to a further development of the carbon capture technology. However, future investigations regarding the process design are required in order reduce the capture cost even more.

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