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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.
131

Avaliação da contagem de células somáticas do leite como indicador da ocorrência de mastite em vacas Gir / Evaluation of milk somatic cell count as an indicator of mastitis occurrence in Gyr cows

Carolina Barbosa Malek dos Reis 31 March 2010 (has links)
Os objetivos deste trabalho foram determinar a sensibilidade e especificidade do limiar de contagem de células somáticas (CCS) de vacas Gir para o diagnóstico de mastite subclínica causada por patógenos primários e secundários e avaliar os efeitos de rebanho, vaca, mês de coleta, quarto mamário, presença de infecção intramamária, tipo de microrganismo e suas interações sobre o logCCS e composição do leite. Avaliou-se a hipótese que o limiar da CCS para detecção de mastite subclínica é igual entre vacas Gir e Holandesas. Foram utilizadas 221 vacas Gir em lactação, provenientes de três fazendas comerciais. Foram coletadas amostras de leite individuais por quarto mamário e compostas uma vez por mês, durante um ano. Foram realizadas análises de CCS, composição do leite e cultura microbiológica. O quarto mamário e a vaca foram considerados unidades experimentais. Para determinar a sensibilidade, especificidade e odds ratio (OR) dos limiares da CCS para identificação de quartos infectados, foram utilizados quatro valores de CCS: 100, 200, 300 e 400 (x 103 células/mL), assim como a correlação entre a CCS e composição do leite. Não houve efeito do rebanho sobre o logCCS para amostras individuais de quartos mamários e compostas, mas vaca dentro de rebanho foi o principal fator responsável pela variação do logCCS. Houve efeito do rebanho sobre a composição do leite, assim como o mês de coleta apresentou efeito tanto sobre o logCCS quanto para a composição do leite, considerando as duas unidades experimentais. A presença de infecção intramamária afetou negativamente a composição do leite, exceto sobre o teor de gordura; sendo que os maiores teores de lactose, proteína e ESD foram encontrados em amostras sem isolamento bacteriano. Os maiores logCCS foram obtidos em amostras infectadas. O limiar da CCS de 100 x 103 células/mL apresentou, em ambas as unidades experimentais, maiores valores de sensibilidade e valor preditivo negativo. O limiar de 200 x 103 células/mL apresentou maior chance da ocorrência de mastite do que o limiar de 100 x 103 células/mL. Foi observada correlação negativa entre CCS com lactose e extrato seco desengordurado (ESD), mas a correlação foi positiva entre CCS com gordura e proteína, tanto em nível de quarto mamário quanto de vaca. Portanto, a composição do leite foi influenciada pela CCS, os teores de lactose e ESD diminuíram em altas CCS, enquanto que as concentrações de gordura e proteína aumentaram. / The aim of this study was to determine the sensibility and specificity of somatic cell count (SCC) threshold in Gyr cows to diagnosis the subclinical mastitis caused by primary and secondary pathogens, and to evaluate the effect of herd, cows, month, mammary quarter, intramammary infection, type of microorganism and their interactions on logSCC and milk composition. The hypothesis to be tested was that the SCC threshold to detection of subclinical mastitis is the same for Holstein and Gir cows. A total of 221 lactation Gir cows from three commercial dairy farms was selected. Composed and quarter individual milk samples were collected once a month, during one year for SCC, milk composition and bacteriological analysis. The mammary quarter and the cow were considered experimental units. To determine the sensibility, specificity and odds ratio (OR) from SCC threshold to identify the infected quarters four values of SCC: 100, 200, 300 and 400 (x 103 cells/mL) were used. It was also evaluated the correlation between SCC and milk composition. There was no effect of herd on logSCC in individuals and composed samples, but cow nested within herd was major factor responsible for the logSCC variation. The month of sampling presented significant effect on logSCC and milk composition in both experimental units. The intramammary infection presence affected negatively the milk composition, except of fat concentration. Higher lactose, protein and non-fat solids (NFS) percentages were found in negative samples and higher logSCC were observed in infected samples. The SCC threshold of 100 x 103 cells/mL presented the major sensibility and negative predictive value for subclinical mastitis detection. The threshold of 200 x 103 cells/mL had higher chance to have mastitis than the threshold of 100 x 103 cells/mL. It was observed a negative correlation between SCC with lactose and NFS; but the correlation was positive between SCC with fat and protein in mammary quarters and cow level. Milk composition was influenced by SCC, once the lactose and NFS percentages decreased in samples with high SCC and the protein and fat concentration increased.
132

Random Variate Generation by Numerical Inversion When Only the Density Is Known

Derflinger, Gerhard, Hörmann, Wolfgang, Leydold, Josef January 2009 (has links) (PDF)
We present a numerical inversion method for generating random variates from continuous distributions when only the density function is given. The algorithm is based on polynomial interpolation of the inverse CDF and Gauss-Lobatto integration. The user can select the required precision which may be close to machine precision for smooth, bounded densities; the necessary tables have moderate size. Our computational experiments with the classical standard distributions (normal, beta, gamma, t-distributions) and with the noncentral chi-square, hyperbolic, generalized hyperbolic and stable distributions showed that our algorithm always reaches the required precision. The setup time is moderate and the marginal execution time is very fast and nearly the same for all distributions. Thus for the case that large samples with fixed parameters are required the proposed algorithm is the fastest inversion method known. Speed-up factors up to 1000 are obtained when compared to inversion algorithms developed for the specific distributions. This makes our algorithm especially attractive for the simulation of copulas and for quasi-Monte Carlo applications. <P> This paper is the revised final version of the working paper no. 78 of this research report series. / Series: Research Report Series / Department of Statistics and Mathematics
133

Online Supplement to "Random Variate Generation by Numerical Inversion When Only the Density Is Known"

Derflinger, Gerhard, Hörmann, Wolfgang, Leydold, Josef January 2009 (has links) (PDF)
This Online Supplement summarizes our computational experiences with Algorithm NINIGL presented in our paper "Random Variate Generation by Numerical Inversion when only the Density Is Known" (Report No. 90). It is a numerical inversion method for generating random variates from continuous distributions when only the density function is given. The algorithm is based on polynomial interpolation of the inverse CDF and Gauss-Lobatto integration. The user can select the required precision which may be close to machine precision for smooth, bounded densities; the necessary tables have moderate size. Our computational experiments with the classical standard distributions (normal, beta, gamma, t-distributions) and with the noncentral chi-square, hyperbolic, generalized hyperbolic and stable distributions showed that our algorithm always reaches the required precision. The setup time is moderate and the marginal execution time is very fast and nearly the same for all these distributions. Thus for the case that large samples with fixed parameters are required the proposed algorithm is the fastest inversion method known. Speed-up factors up to 1000 are obtained when compared to inversion algorithms developed for the specific distributions. Thus our algorithm is especially attractive for the simulation of copulas and for quasi-Monte Carlo applications. / Series: Research Report Series / Department of Statistics and Mathematics
134

Modeling of geohydrological processes in geological CO2 storage – with focus on residual trapping

Rasmusson, Kristina January 2017 (has links)
Geological storage of carbon dioxide (CO2) in deep saline aquifers is one approach to mitigate release from large point sources to the atmosphere. Understanding of in-situ processes providing trapping is important to the development of realistic models and the planning of future storage projects. This thesis covers both field- and pore-scale numerical modeling studies of such geohydrological processes, with focus on residual trapping. The setting is a CO2-injection experiment at the Heletz test site, conducted within the frame of the EU FP7 MUSTANG and TRUST projects. The objectives of the thesis are to develop and analyze alternative experimental characterization test sequences for determining in-situ residual CO2 saturation (Sgr), as well as to analyze the impact of the injection strategy on trapping, the effect of model assumptions (coupled wellbore-reservoir flow, geological heterogeneity, trapping model) on the predicted trapping, and to develop a pore-network model (PNM) for simulating and analyzing pore-scale mechanisms. The results include a comparison of alternative characterization test sequences for estimating Sgr. The estimates were retrieved through parameter estimation. The effect on the estimate of including various data sets was determined. A new method, using withdrawal and an indicator-tracer, for obtaining a residual zone in-situ was also introduced. Simulations were made of the CO2 partitioning between layers in a multi-layered formation, and parameters influencing this were identified. The results showed the importance of accounting for coupled wellbore-reservoir flow in simulations of such scenarios. Simulations also showed that adding chase-fluid stages after a conventional CO2 injection enhances the (residual and dissolution) trapping. Including geological heterogeneity generally decreased the estimated trapping. The choice of trapping model may largely effect the quantity of the predicted residual trapping (although most of them produced similar results). The use of an appropriate trapping model and description of geological heterogeneity for a site when simulating CO2 sequestration is vital, as different assumptions may give significant discrepancies in predicted trapping. The result also includes a PNM code, for multiphase quasi-static flow and trapping in porous materials. It was used to investigate trapping and obtain an estimated trapping (IR) curve for Heletz sandstone.
135

Life cycle sustainability assessment of electricity generation : a methodology and an application in the UK context

Stamford, Laurence James January 2012 (has links)
This research has developed a novel sustainability assessment framework for electricity technologies and scenarios, taking into account techno-economic, environmental and social aspects. The methodology uses a life cycle approach and considers relevant sustainability impacts along the supply chain. The framework is generic and applicable to a range of electricity technologies and scenarios. To test the methodology, sustainability assessments have been carried out first for different technologies and then for a range of possible future electricity scenarios for the UK. The electricity options considered either contribute significantly to the current UK electricity mix or will play a greater role in the future; these are nuclear power (PWR), natural gas (CCGT), wind (offshore), solar (residential PV) and coal power (subcritical pulverised). The results show that no one technology is superior and that certain tradeoffs must be made. For example, nuclear and offshore wind power have the lowest life cycle environmental impacts, except for freshwater eco-toxicity for which gas is the best option; coal and gas are the cheapest options, but both have high global warming potential; PV has relatively low global warming potential but high cost, ozone layer and resource depletion. Nuclear, wind and PV increase certain aspects of energy security but introduce potential grid management problems; nuclear also poses complex risk and intergenerational questions. Five potential future electricity mixes have also been examined within three overarching scenarios, spanning 2020 to 2070, and compared to the present-day UK grid. The scenarios have been guided by three different approaches to climate change: one future in which little action is taken to reduce CO2 emissions (‘65%’), one in which electricity decarbonises by 80% by 2050 in line with the UK’s CO2 reduction target (‘80%’), and one in which electricity is virtually decarbonised (at the point of generation) by 2050, in line with current policy (‘100%’).In order to examine the sustainability implications of these scenarios, the assessment results from the present-day comparison were projected forward to describe each technology in future time periods. Additional data were compiled so that coal with carbon capture and storage (CCS) – a potentially key future technology – could be included. The results of the scenario analyses show that the cost of generating electricity is likely to increase and become more capital-intensive. However, the lower-carbon scenarios are also at least 87% less sensitive to fuel price volatility. Higher penetration of nuclear and renewables generally leads to better environmental performance and more employment, but creates unknown energy storage costs and, in the case of nuclear power and coal CCS, the production of long-lived waste places a burden of management and risk on future generations. Therefore, the choice of the ‘most sustainable’ electricity options now and in the future will depend crucially on the importance placed on different sustainability impacts; this should be acknowledged in future policy and decision making. A good compromise requires strategic government action; to provide guidance, specific recommendations are made for future government policy.
136

The future of captured CO2 : Analysis of the role of carbon capture, storage and utilisation in a sustainable Europe

Granér, Oscar, Johansson, Daniel January 2022 (has links)
The energy transition is one of the largest challenges our global society is facing. In 2015, the United Nations acknowledged the Paris Agreement, where the world’s nations were united to limit the global warming well below 2 °C in comparison with pre-historic levels. One of the measures to tackle this challenge that have been proposed by both the International Energy Agency and the European Union is carbon capture and storage or utilisation (CCUS). The concept of CCUS is relatively old but has in light of climate mitigation measures been identified as vital since carbon dioxide (CO2) either can be permanently stored or sequestered into products and materials. Previous research has shown a large potential in CCUS, and that it has a key role in enabling and achieving net-zero climate scenarios. However, large-scale and widely distributed CCUS facilities has not yet been deployed, and it is not fully clear which aspects that are the most important affecting the deployment and how this can be facilitated. This study aims to investigate the current and future market of captured CO2 in Europe during the next decade. The study aims to fill the knowledge gap on how policies affect the development of CCUS, the drivers and barriers that current actors have identified within the field, and lastly, possible pathways in which CO2 can be used. This study was performed using a literature scoping review and interviews with relevant CCUS actors in different parts of the value-chain. The results show CCUS is recognised as an important tool within the European Union to reach the climate goals set out by the European Commission. The development and further deployment of CCUS are however prevented due to economic and legislative barriers, of which low carbon pricing, such as the EU ETS, is identified as the main barrier against making CCUS commercially competitive. Additional legislative barriers are connected to the cross-national trade and export of CO2, as well as a lacking framework on verification and monitoring of captured CO2 and the trade with carbon removal credits. The results also show that CCUS initially will be developed at industrial clusters in the North-West Europe, where shared infrastructure is recognised as an enabler due to sharing risks of investments. The main focus within Europe is on offshore storage rather than CCU due to its large sequestering potential, although CCU can be relevant in regions lacking infrastructure for the transportation of CO2. Regarding the investigated utilisation options, synthetic fuels, building materials, and polymers have been identified to have high potential even if they are not believed to have a high influence as a climate mitigation measure in comparison with CCS. It is concluded that viable business models and cost-effective infrastructure solutions are essential for the European CCUS industry. Much of the deployment is however dependent on clear, beneficial frameworks and policies stating the rules and facilitating the economics of CCUS. Nevertheless, it is expected that especially the European CCS sector will grow in Europe in the upcoming decade, although the role of CCU should not be neglected.
137

DIFFUSION CONSTRICTION OF IONS USING VARYING FIELDS FOR ENHANCED SEPARATION, TRANSMISSION AND SIZE RANGE IN ION MOBILITY SYSTEMS

Xi Chen (12456690) 26 April 2022 (has links)
<p>    Drift tubes (DT) are prominent tools used in Ion Mobility Spectrometry (IMS) to separate ions in the gas phase due to their difference in mobility. While prominently used for small ions (< 10nm), their use for larger particles (up to 100nm) is limited and can only be attempted at atmospheric pressure due to diffusion. A system that specializes in high sensitivity larger particles (up to 1000nm) is the Differential Mobility Analyzer (DMA), but lacks in resolution (< 10 for particles 30-1000nm). The idea behind this work is to be able to design a new IMS system based on similar<br> principles to the DT but that allows high resolution and sensitivity for a large range of sizes if possible. The primary idea revolves around the principle of non-constant linear fields to try and control the width of the ion packet as it travels through the system. The first attempt was an Inverted Drift Tube (IDT) which lacked sufficient<br> sensitivity. This was followed by the development of the Varying Field Drift Tube (VFDT) which was the first of such systems to perform better than a regular DT, but only marginally. Finally, the last version of the system included a secondary pulse and labeled High Voltage Pulse - Varying Field Drift Tube (HVP-VFDT), which solved<br> some of the issues of the VFDT and was able to achieve resolving powers of 250, 3-5 times higher than regular DT.</p> <p><br>    In the IDT system, a gas flow is used to drive the packet of ions through the drift region while a linearly increasing electric field which is in the opposite direction of the flow is used to slow down the ions and separate them. In this regime it is the largest ions that arrive at the detector first, hence the name Inverted Drift Tube.This technique would allow larger ions and particles to be detected. At the same time, the linear field can be shown to have diffusion constriction (auto-correction) properties, where the broad distributions may be narrowed in the axial direction. However, the gas flow is difficult to control well and the parabolic velocity profile of the gas flow in the tube is a unfavorable factor for the system. </p> <p><br></p> <p>    To avoid the issue of the parabolic velocity but still take into account the VFDT takes the advantage of the diffusion auto-correction, the gas flow is suppressed and a linearly decreasing field is used to drive the ions. By solving the Nernst-Planck equation, we show that the VFDT has a spatial resolving power that is much higher than that of the regular DT. A DT was built and tested using a mixture of tetraalkylammonium salts. The transformation from the raw variable arrival time distribution to collision cross section or mobility diameter is derived and the linear relationship<br> makes it simple for calibration and transformation. A resolving power of over 90 is achieved experimentally although higher resolving powers were expected theory. <br>  <br>  It turns out that the difference between theory and experiments had to do with the fact that in the VFDT, the spatial and time resolving powers are different.This<br> is due to the low drift velocity at the end of the drift tube. To increase this velocity, a high voltage pulse is applied at a certain time depending on the ion/s of interest with a new system, HVP-VFDT. The system was tested numerically and experimentally where several parameters where tested resulting in a higher resolving powers when compared with DT and VFDT systems.The simulation results showed that the transmission efficiency and resolving power can be controlled by raising or lowering the field. Overall, the experimental setup tested reached resolving powers of 250 with moderate gate pulses. The HVP-VFDT system also shows that the distribution may be narrowed over the initial one, something impossible with a real drift tube and<br> opens a myriad of possibilities, including resolving powers of several thousands under low pressure and RF fields. <br>    <br>  The next step will be to couple the system to a Mass Spectrometer which is expected to be completed in the near future. To understand how a DT works with   RF fields and low pressure, a collaboration was done with David Clemmer’s lab and his 4 meter drift tube that can achieve resolutions of 150 in Helium at 4torr. Here, we tested a set of polymers and compared the results to those acquired in Nitrogen with a DMA. The shape and structure of the polymers in the gas phase was studied showing<br> self-similar assemblies that corresponds to a globule with an appendix sticking out. <br>  <br>    </p>
138

Integrated Systems Analyses of Using Geologically Stored CO2 and Sedimentary Basin Geothermal Resources to Produce and Store Energy

Ogland-Hand, Jonathan D. 24 June 2019 (has links)
No description available.
139

How Learning Assistants Impact Undergraduate STEM Students

Sloan, Tyler Jackson 30 April 2020 (has links)
No description available.
140

Carbon Capture and Storage : And the Possibilities in Sweden / Carbon Capture and Storage : Och möjligheterna i Sverige

Chowdhury, Risha, Malmberg, Sofie January 2023 (has links)
The Paris Agreement aims to limit global warming to 1.5 degrees Celsius, and Sweden has set a goal toreach net-zero emissions by 2045. Carbon Capture and Storage (CCS) is one method that can reducecarbon dioxide emissions. The industry and transportation sectors are the biggest sources of emissionsin Sweden, requiring technological developments and increased investment to reduce their carbondioxide (CO2) emissions. The Geological Survey of Sweden (SGU) is responsible for controls,supervision, operation, and construction of activities connected with carbon dioxide (CO2) storage. SGUbelieves that the storage conditions in Sweden are poor. Sedimentary, basaltic and ultramafic rock ispreferable for CO2 storage, but finding the right sort of bedrock at the right depth and with the rightvolumes and porosity is the challenge. Hence it is in question to collaborate with nations in the northern sea, in order to transport and storageCO2 which would lessen the burden of needing to build new infrastructure. There are a few upcomingCarbon Capture and Utilisation (CCU) projects in Sweden but from the industry’s point of view, thepriority seems to be mostly on Bio-CCS. However, there is still interest for CCS technology in industrialproduction such as steel or cement and also Direct Air Capture (DAC) in the near future. Due to thehigh cost of CCS, funding through the Swedish Energy Agency and EU is vital in order to make iteconomically viable. Other Cost reducing solutions such as relocation on old oil and gas fields orarranging CCS hubs are possible. In summary, this study concludes that CCS is not currently a feasible technique in order to reduce CO2 from the atmosphere, given the current state and costs for it. If the technology becomes more energyefficient and when financial means are in place, the future is bright for CCS. It is extremely relevantthat this technology continues to develop into a better, cheaper and faster way to capture CO2 and reduceemissions of the effective greenhouse gases. / Parisavtalet syftar till att begränsa den globala uppvärmningen till 1,5 grader Celsius och Sverige harockså satt som mål att nå nettonollutsläpp till år 2045. Ett sätt att nå dessa mål kan vara med teknikenför Carbon Capture and Storage (CCS) som är en metod för att minska koldioxidhalten i atmosfären.Den här rapporten syftar till att undersöka med hjälp av litteraturstudier och intervjuer hur genomförbarCCS är som teknik för att minska koldioxidutsläppen samt hur man även kan minska på den befintligamängden koldioxid som redan finns i luften. Huvudfokuset är att undersöka hur CCS fungerar och vilkakostnader som är involverade. Eftersom koldioxid (CO2) är en av de växthusgaser som bidrar mest tillden globala uppvärmningen är det viktigt att vidta åtgärder för att minska den. Det är inte bara utsläppenav CO2 som måste minska utan även mängden CO2 som redan finns i atmosfären. Forskning kring CCSär därför viktig för att hitta nya sätt att effektivisera metoden och göra den mer genomförbar. Naturvårdsverket ger ut en årlig rapport som utvärderar landets framsteg mot att nå sina miljömål,inklusive “Begränsad klimatpåverkan”. Rapporten konstaterar att även om EU och Sverige har minskatutsläppen ökar de fortfarande globalt sett. Industri- och transportsektorn identifieras som de störstautsläppskällorna i Sverige. Den svenska förordningen om CCS regleras av miljöbalken som testar kollagringi geologiska formationer som en miljöfarlig verksamhet och den separerade CO2 ses som avfall.Sverige har ännu inte någon kommersiell CCS-anläggning men regeringen har föreslagit att svenskaindustrier bör införa CCS för att minska dessa utsläpp. Både Sverige och EU har investerat i att utvecklateknik för att minska användningen av fossila bränslen och underlätta för användningen av CCS. CCS processen består av tre huvudsteg: avskiljning och separering av CO2, transport samt lagring elleråteranvändning. Alla typer av nuvarande CCS-metoder kräver en stor mängd energi och de flesta avdem separerar CO2 från industriella förbränningar. Direct Air Capture (DAC) är en annaninfångningsteknik som är mer flexibel när det gäller placering, men också dyrare än de andra teknikerna.Transporten av den infångade CO2 kan ske med lastbil, tåg, fartyg eller rör. De mest genomförbaraalternativen är dock rörledningar och via fartyg på grund av deras transportkapacitet. Rörledningarkräver en välutvecklad infrastruktur, vilket gör dem kostsamma, men de är det mest genomförbaraalternativet för att separera CO2 från landbaserade anläggningar och transportera dem till närliggandelagringsplatser. Geologisk lagring av CO2 kan göras både på land och till havs. Injektion till dengeologiska formationen vid lagringsplatser sker via borrhål. CO2 förvätskas och ersätter denursprungliga vätskan i bergmaterialets porer i berggrunden och reagerar så småningom med berget ochbildar nya mineraler i berggrunden. Sveriges Geologiska Undersökning (SGU) ansvarar för kontroller, tillsyn, drift och uppförande avverksamheter kopplade till CO2-lagring. Geologin i Sverige lämpar sig dock generellt sett inte förlagring av CO2, förutom för vissa sydliga områden. Nordsjön har en del gynnsamma förutsättningar förCO2-lagring och det finns även potentiella geologiska formationer i södra Östersjön. Sedimentära,basaltiska eller ultramafiska bergarter är att föredra för geologisk CO2-lagring. Den största utmaningenär att hitta rätt sorts berggrund på rätt djup och med rätt volym och porositet. Den största svårigheten med CCS är den höga kostnaden, vilket bidrar till att hämma den utbreddaanvändningen. Kostnaden för CCS inkluderar olika faktorer som infångningsmetod, transportmedel,lagringsplats och övervakning över lagringen. Bland dessa är infångningen den dyraste fasen avtekniken, följt av lagring, transport och övervakning. Kostnaderna för varje fas har analyserats över2olika intervaller med hänsyn till lägre, medelstora och högre kostnader men även beroende på regiondå kostnaden kan variera beroende på ländernas förutsättningar. Infångningsfasen av CCS har betydande kostnadsvariationer beroende på vilken metod som används,renheten hos den infångade CO2 samt den energi som krävs för avskiljningsprocesserna.Högkoncentrerade CO2-strömmar har lägre bearbetningskostnader än lågkoncentrerade. DAC är förnärvarande den dyraste infångningsmetoden. Transportkostnader för CO2 inkluderar kostnaderrelaterade till infrastruktur, drift, underhåll, konstruktion och markanvändning. Kostnaden för transportmed rör beror på faktorer som diameter, avstånd och flödeshastighet. Högre flödeshastigheter genomrörledningar kan minska transportkostnaderna. Lagringskostnader för CO2 omfattar utgifter förborrning, infrastruktur, projektledning, licensiering och platsval. Geologisk lagring på land är förnärvarande mer kostnadseffektivt på grund av de utmaningar och högre kostnader som är förknippademed geologisk lagring till havs. Övervakningskostnader är till exempel screening och utvärdering avlagringsplatser samt uppgifter som datainsamling, platsrankning, brunnsinstallation och seismiskautvärderingar. Att minska energitillgången för infångning, förbättra val av lösningsmedel vid separationsfasen,återanvända och utveckla befintlig infrastruktur är exempel som kan hjälpa till att sänka kostnadernaför CCS-processen och främja en bredare användning. Ett annat förslag för att öka den ekonomiskalönsamheten är genom att implementera CCS nav eller kluster. Dessa CCS nav eller kluster ger företagmöjligheten att samordna infrastrukturen för sina CCS-anläggningar. Detta kan lindra den ekonomiskabördan att bygga upp egen kostsam infrastruktur. Nedlagda olje- och gasfält kan återbrukas för CCS- anläggningar då efterfrågan av fossila bränslenminskar. Istället för att riva ner verksamheterna för fossilt bränsle, exploatera ny mark och borra nyahål kan olje- och gasfälten i exempelvis norra haven återbrukas för CCS- anläggningar. Danmark är ettav de första länderna som har tagit initiativet att omvandla oljeanläggningar till koldioxidlagringanläggningar. Det är möjligt att söka om ekonomiskt stöd från Energimyndigheten eller EU för att få stöd till främstBio-CCS projekt men även andra. Detta är i syfte för att underlätta en fri marknad för tekniker somimplementerar koldioxidinfångst. Ambitionen med detta stödsystem är för att realisera en infångst av10 miljoner CO2 via Bio-CCS och minst 2 miljoner CO2/år för andra CCS tekniker. Genom omvändauktion får det företag som kan erbjuda infångad CO2/ton med Bio-CCS teknik för lägst pris, ta del avstödsystemet. EU har även initiativ att finansiera CCS-projekt genom CETPartnership eller EU:sinnovationsfond vars syfte är att stödja forskning och innovation inom CCS. Sammanfattningsvis kom denna studie fram till att CCS inte är genomförbart idag som en teknik för attminska CO2 från atmosfären med hänsyn till nuläget och kostnaderna för att implementera. Om teknikenenergi effektiviseras och när ekonomiska medel finns på plats är framtiden ljus för CCS. Det är oerhörtrelevant att denna teknik fortsätter att utvecklas till ett bättre, billigare och snabbare sätt att fånga uppCO2 och minska utsläppen av de effektiva växthusgaserna. Regeringen och industrin måste därförsamarbeta bättre för att underlätta regelverk som främjar och möjliggör samarbete inom CCS-branschendå många myndigheter lyfter fram att CCS är en nödvändig teknik för framtiden för att uppnå klimatneutralitet.

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