Orientador: Humberto Tonhati / Resumo: A mastite é a enfermidade que mais causa prejuízos de ordem quantitativa e qualitativa nos sistemas de produção de leite no mundo. A prevenção e controle da doença precisam envolver atividades práticas e eficientes que auxiliem a tomada de decisões rápidas na fazenda. Os métodos de triagem para o diagnóstico da mastite aplicados às búfalas leiteiras são aqueles desenvolvidos especificamente para as vacas. Assim, o objetivo geral da tese foi estudar a mastite subclínica em búfalas e avaliar os métodos de triagem que auxiliam o diagnóstico da doença na fazenda. O trabalho se divide em quatro capítulos que tratam de: revisar a literatura sobre as temáticas (I); caracterizar o leite de quartos mamários com e sem infecção intramamária, e avaliar a associação entre a presença de infecção intramamária e as características microbiológicas do leite de quartos mamários de búfalas, posição dos tetos e os resultados dos métodos de triagem (II); e avaliar os testes rápidos California Mastitis Test , Somaticell e condutividade elétrica como métodos de triagem para auxiliar o diagnóstico da mastite subclínica em búfalas diretamente na fazenda (III). O estudo foi realizado em um rebanho de búfalas no estado do Rio Grande do Norte. Foram colhidas 533 amostras de leite de quartos mamários que foram submetidas à contagem eletrônica de células somáticas (CCS), aos testes de triagem (California Mastitis Test – CMT, teste Somaticell - SO e condutividade elétrica – CEL) e ao exame microbiológico pa... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Mastitis is the disease that causes the most quantitative and qualitative losses in milk production systems in the world. Disease prevention and control need to involve practical and efficient actions that may help on decision-making on farm. Screening methods applied for mastitis diagnosis in dairy buffaloes are those developed specifically for cows. Thus, the objective of the thesis was to study subclinical mastitis in buffaloes and to evaluate the screening methods that help the disease diagnosis in farm. The work is divided into four chapters that deal with: reviewing the literature on the themes (I); to characterize breast milk with and without intramammary infection and to evaluate the association between the presence of intramammary infection and microbiological characteristics of buffalo milk, teat position, and the results of screening methods (II); and evaluate the California Mastitis Test (CMT), Somaticell (SO) and electrical conductivity (EC) rapid tests as a screening method to assist the diagnosis of subclinical mastitis in buffaloes on farm (III). The work was developed in a buffaloes commercial herd in the Rio Grande do Norte state. A total of 533 randomly selected milk samples were obtained and submitted to electronic somatic cell count (SCC), screening tests (CMT, SO and EC) and microbiological examination for diagnosis of subclinical mastitis (IMM: positive/negative), infection classification (negative, contagious, environmental, mixed and opportunistic) an... (Complete abstract click electronic access below) / Doutor

Les problèmes environnementaux, notamment ceux qui, liés au réchauffement global, ont attiré de plus en plus l’attention des décideurs de l'entreprise. Leurs préoccupations sur ces problèmes les conduisent à une réflexion de réorganisation de leurs activités. Pour les entreprises industrielles qui doivent faire face au problème des émissions de CO2, le soutien de gouvernement local qui concerne la gestion des émissions de CO2 devient non négligeable. Dans cette thèse, nous interviewons 50 décideurs de l'industrie, le gouvernement et la communauté universitaire. L’importance du problème des émissions de CO2 dans le choix de site est globalement évaluée. Nos observations suggèrent que le problème du CO2 est un facteur mineur dans la localisation des sites. Il peut être intégré dans le coût global. Pour les autorités locales, il n'est pas nécessaire d'investir dans les infrastructures de traitement des émissions de CO2 à l'heure actuelle. Nos résultats fournissent ainsi une meilleure compréhension du problème des émissions de CO2 pour les décideurs des industries locales. / Environmental problems, especially those related to the global warming have attracted extensive attention from the decision makers of companies. Their concerns on the environmental problems lead them to a reform of the mode of management. For the decision makers from industry who have to face the CO2 problem, whether they can be supported by the local government with respect to managing CO2 emissions becomes non trivial. In this thesis, we interviewed 50 decision makers from industries, government, and academic community. The significance of the CO2 problem in site selection is comprehensively evaluated. Our observations suggest that the CO2 problem is a minor factor. It can be measured by the cost. For the local government, there is no need to invest in the infrastructures of CO2 treatment at present. Our results thus provide a better understanding of the CO2 problem for the decision makers of local industries.

The reduction of greenhouse gas emissions is important to keep climate change under control. One of the largest CO2 emitters of the Swedish industries is the steel industry. This is, among others, due to the need of heat treatments and reheating processes depending on high temperatures and fossil fuels. The business organisation Jernkontoret and their department for energy and furnace technique is working towards reducing the emissions for these processes and one area of research is the carboncapture and storage (CCS) techniques. This report aims to give an overview of existing and emerging CCS techniques applicable for the reheating and heat treating furnaces, along with evaluating one post-combustion carbon capture technique for different cases provided by some involved companies. The carbon capture technique investigated in this project can be divided into three main sections; Oxyfuel combustion, pre-combustion and post-combustion capture. Oxyfuel relies on the usage of pure oxygen instead of air for the combustion of the fuel, this gives a high CO2 concentration in the flue gas (80-98%). Concentrations below 95% require further purification before compression and transportation to storage. Using pre-combustion capture the CO2 is removed before the combustion, this can be done by reformingthe used fossil fuel to a syngas (a gas with a high H2 and CO concentrations). The CO2 is formed by passing the syngas through a water-gas shift, which also increases the H2 concentration further. The CO2 can then be removed relying on reversible chemical reactions or the affinity between the CO2 and an absorbent. The post-combustion carbon capture also relies on reversible chemical reactions or affinity to an absorption medium, usually an amine solvent. The bond is then broken in the desorption unit, creating a pure CO2 stream and a reusable absorbent. The case studies were done only for a post-combustion capture process with a MEA-water solvent (20%) as the absorption medium. The simulation program Aspen Plus was used both for the technicaland economical values, executed by the PhD student Nan Wang at LTU. The values were interpolated/extrapolated nonlinear for each given case. Six different cases were given by four companies, four conventional furnaces and two oxyfuel furnaces. Evaluations for the oxyfuel furnaces were excluded, due to big differences between the model and case values and since the technique evaluated is not implementedat oxyfuel plants. The evaluations done for the conventional furnace cases gave a total cost of between 86 - 126 $/tonne captured CO2. This has to be viewed as a high cost investment even without having a full economic evaluation regarding cost for transportation and storage included.

Sverige har som mål att senast år 2045 inte ha några nettoutsläpp av växthusgaser till atmosfären. Ett område som diskuteras är byggsektorn och dess utsläpp, vilket har lett till åtgärder i form av införandet av klimatdeklarationer. Dessa ska revideras med krav i form av gränsvärden som förväntas implementeras senast år 2027. Ett område med betydande utsläpp inom byggsektorn är användandet av betong som material vid nybyggnation, varvid intresset av klimatförbättrade varianter har ökat drastiskt under senaste åren.  Denna studie genomförs i samarbete med Wallenstam där det övergripande målet är att identifiera hur marknaden för klimatförbättrad betong står sig gentemot de kommande gränsvärden som förväntas införas till klimatdeklarationer senast år 2027. Ett av målen är att genom en beräkning visa hur en byggnads klimatutsläpp påverkas vid ett användande av klimatförbättrad betong istället för traditionell betong, där ett referensprojekt från Wallenstam har använts. Arbetet ska även, genom en intervjustudie, redogöra för vilka förutsättningar leverantörer av klimatförbättrad betong står inför att ta fram klimatneutral betong. Även om vissa leverantörers produkter gav ett lägre klimatutsläpp än andra visade resultatet ingen större avvikelse hos någon av leverantörerna. Samtliga undersökta leverantörer har produkter som ger ett lägre klimatavtryck än det gränsvärde som är baserat på referensprojektet. Alla undersökta kombinationer av leverantörernas produkter visade ett resultat med en minskning på över 20% där kombinationen med lägst klimatavtryck, som enbart innehåller platsgjuten betong, visade en minskning av byggnadens totala utsläpp på 38.4%. Intervjustudien visade att implementering av CCS-teknik och andra alternativa bindemedel krävs för att nå en klimatneutral betong. / Sweden aims to have zero net emissions of greenhouse gases by the year 2045. A major contributor to emissions is the construction sector, which has led to the introduction of climate declarations. These will be revised with requirements in the form of limit values that are expected to be implemented by the year 2027. As concrete accounts for a large part of the emissions from the construction sector, interest in climate-improved variants has increased significantly in recent years. This study is carried out in collaboration with Wallenstam, where the overall goal is to identify how the market for climate-improved concrete stands in relation to the future limit values that are expected to be introduced in climate declarations by the year 2027. One of the goals is to show how a building's climate emissions are affected by the use of climate-improved concrete instead of traditional concrete. For this, a reference project from Wallenstam has been used. The study will also, through an interview study, account for the conditions that suppliers of climate-improved concrete are facing to produce climate-neutral concrete. Although some suppliers' products had lower climate emissions than others, the results did not show any major deviation at any of the suppliers. All surveyed suppliers have products that have a lower climate footprint than the limit value based on the reference project. All examined combinations of the suppliers' products showed a result with a reduction of over 20%, where the combination with the lowest climate footprint, which only contains cast-in-place concrete, showed a reduction in the building's total emissions of 38.4%. The interview study showed that implementation of CCS technology and other alternative binders is required to reach a climate-neutral concrete.

Bioenergy with carbon capture and storage is emphasized by the Intergovernmental Panel on Climate Change as a key mitigation option to reach the Paris Agreement goal of 2 degrees Celsius but the required need of large-scale facilities is yet to be developed and is therefore in large theoretical. Norway is one country often portraited as a forerunner in the field especially when it comes to offshore storage. How media is framing the technology can impact how society responds to it. This thesis explores how bioenergy with carbon capture and storage is constructed in Norwegian news media between 2005 and 2020. This is done by conducting a discourse analysis based on Marten Haajers analytical approach and reflect on how the constructed story lines are aligned with the current policy path in Norway. The results show that the three discourses Survivalism, Promethenaism and Ecological modernization have dominated the Norwegian news media and the notion of bioenergy with carbon capture and storage. The majority of published articles in the sample were found to be supportive of the technology but there are also more critical voices who above all advocate an increased focus on the forests’ mitigation potential. The discourses constructed in the news media have clear similarities with the ongoing policy path on bioenergy with carbon capture and storage, as both voice the idea that technological development is well aligned with striving towards sustainability.

There is a general consensus in the literature that carbon capture and storage (CCS), a technology that controls CO2 emissions from fossil fuel power plants, figures to be a critical technology to reduce CO2 emissions to CO2 concentration stabilization levels prescribed in the literature. We completed three projects that advance the understanding of how technical change in carbon capture affects both near-future costs of CCS and the economy in the long term. First, we conducted a literature review of near-future capture cost estimates in order to get an idea of how expensive carbon capture will be in the near-future. The literature indicates that pre-combustion capture is the least expensive carbon capture technology because its combustion process best facilitates carbon capture. Second, we explored the limits of incremental technical change in each near-future capture technology using a performance-cost model. The results of the sensitivity analysis showed that pre-combustion capture could be the least expensive capture technology after incremental technical change has occurred. Third, we used an integrated assessment model (IAM) to investigate how rapid incremental and breakthrough technical change in carbon capture could impact the electric energy market, total CO2 abatement cost and CO2 price over time. We modeled breakthrough technical change using data from a paper in the literature that provides cost and performance estimates for a radical carbon capture technology still in the early stages of research and development (R&D) (Baker, Chon, & Keisler, 2009). CCS dominates electricity market share over time given a chemical looping breakthrough.

Yes / Carbon capture and storage (CCS) has attracted renewed interest in the re-evaluation of the equations of state (EoS) for the prediction of thermodynamic properties. This study also evaluates EoS for Peng–Robinson (PR) and Soave–Redlich–Kwong (SRK) and their capability to predict the thermodynamic properties of CO2-rich mixtures. The investigation was carried out using machine learning such as an artificial neural network (ANN) and a classified learner. A lower average absolute relative deviation (AARD) of 7.46% was obtained for the PR in comparison with SRK (AARD = 15.0%) for three components system of CO2 with N2 and CH4. Moreover, it was found to be 13.5% for PR and 19.50% for SRK in the five components’ (CO2 with N2, CH4, Ar, and O2) case. In addition, applying machine learning provided promise and valuable insight to deal with engineering problems. The implementation of machine learning in conjunction with EoS led to getting lower predictive AARD in contrast to EoS. An of AARD 2.81% was achieved for the three components and 12.2% for the respective five components mixture.

Yes / The process of capturing and storing carbon dioxide (CCS) was previously considered a crucial and time-sensitive approach for diminishing CO2 emissions originating from coal, oil, and gas sectors. Its implementation was seen necessary to address the detrimental effects of CO2 on the atmosphere and the ecosystem. This recognition was achieved by previous substantial study efforts. The carbon capture and storage (CCS) cycle concludes with the final stage of CO2 storage. This stage involves primarily the adsorption of CO2 in the ocean and the injection of CO2 into subsurface reservoir formations. Additionally, the process of CO2 reactivity with minerals in the reservoir formations leads to the formation of limestone through injectivities. Carbon capture and storage (CCS) is the final phase in the CCS cycle, mostly achieved by the use of marine and underground geological sequestration methods, along with mineral carbonation techniques. The introduction of supercritical CO2 into geological formations has the potential to alter the prevailing physical and chemical characteristics of the subsurface environment. This process can lead to modifications in the pore fluid pressure, temperature conditions, chemical reactivity, and stress distribution within the reservoir rock. The objective of this study is to enhance our existing understanding of CO2 injection and storage systems, with a specific focus on CO2 storage techniques and the associated issues faced during their implementation. Additionally, this research examines strategies for mitigating important uncertainties in carbon capture and storage (CCS) practises. Carbon capture and storage (CCS) facilities can be considered as integrated systems. However, in scientific research, these storage systems are often divided based on the physical and spatial scales relevant to the investigations. Utilising the chosen system as a boundary condition is a highly effective method for segregating the physics in a diverse range of physical applications. Regrettably, the used separation technique fails to effectively depict the behaviour of the broader significant system in the context of water and gas movement within porous media. The limited efficacy of the technique in capturing the behaviour of the broader relevant system can be attributed to the intricate nature of geological subsurface systems. As a result, various carbon capture and storage (CCS) technologies have emerged, each with distinct applications, associated prices, and social and environmental implications. The results of this study have the potential to enhance comprehension regarding the selection of an appropriate carbon capture and storage (CCS) application method. Moreover, these findings can contribute to the optimisation of greenhouse gas emissions and their associated environmental consequences. By promoting process sustainability, this research can address critical challenges related to global climate change, which are currently of utmost importance to humanity. Despite the significant advancements in this technology over the past decade, various concerns and ambiguities have been highlighted. Considerable emphasis was placed on the fundamental discoveries made in practical programmes related to the storage of CO2 thus far. The study has provided evidence that despite the extensive research and implementation of several CCS technologies thus far, the process of selecting an appropriate and widely accepted CCS technology remains challenging due to considerations related to its technological feasibility, economic viability, and societal and environmental acceptance.

Yes / Capturing and storing CO2 (CCS) was once regarded as a significant, urgent, and necessary option for reducing the emissions of CO2 from coal and oil and gas industries and mitigating the serious impacts of CO2 on the atmosphere and the environment. This recognition came about as a result of extensive research conducted in the past. The CCS cycle comes to a close with the last phase of CO2 storage, which is accomplished primarily by the adsorption of CO2 in the ocean and injection of CO2 subsurface reservoir formation, in addition to the formation of limestone via the process of CO2 reactivity with reservoir formation minerals through injectivities. CCS is the last stage in the carbon capture and storage (CCS) cycle and is accomplished chiefly via oceanic and subterranean geological sequestration, as well as mineral carbonation. The injection of supercritical CO2 into geological formations disrupts the sub-surface’s existing physical and chemical conditions; changes can occur in the pore fluid pressure, temperature state, chemical reactivity, and stress distribution of the reservoir rock. This paper aims at advancing our current knowledge in CO2 injection and storage systems, particularly CO2 storage methods and the challenges encountered during the implementation of each method and analyses on how key uncertainties in CCS can be reduced. CCS sites are essentially unified systems; yet, given the scientific context, these storage systems are typically split during scientific investigations based on the physics and spatial scales involved. Separating the physics by using the chosen system as a boundary condition is a strategy that works effectively for a wide variety of physical applications. Unfortunately, the separation technique does not accurately capture the behaviour of the larger important system in the case of water and gas flow in porous media. This is due to the complexity of geological subsurface systems, which prevents the approach from being able to effectively capture the behaviour of the larger relevant system. This consequently gives rise to different CCS technology with different applications, costs and social and environmental impacts. The findings of this study can help improve the ability to select a suitable CCS application method and can further improve the efficiency of greenhouse gas emissions and their environmental impact, promoting the process sustainability and helping to tackle some of the most important issues that human being is currently accounting global climate change. Though this technology has already had large-scale development for the last decade, some issues and uncertainties are identified. Special attention was focused on the basic findings achieved in CO2 storage operational projects to date. The study has demonstrated that though a number of CCS technologies have been researched and implemented to date, choosing a suitable and acceptable CCS technology is still daunting in terms of its technological application, cost effectiveness and socio-environmental acceptance.

The present work deals with capture and storage of carbon dioxide from biogases by bond- ing to alkaline earth metals from power plant ashes. The aim is to achieve the feed-in standard in Germany for the natural gas grid by binding CO2 in a long-term stable and environmentally compatible manner. In addition, the ash quality is to be improved by reduced mobility of critical metals such as lead, zinc and cadmium, and calcium carbonate is to be recovered as a valuable material in addition to the biomethane. In several experimental setups from laboratory scale to pilot plant, it was shown that both carbon dioxide and hydrogen sulfide can be captured and stored in large quantities of ash residues. Both the use of a packed column to compensate for the poor absorption and reaction kinetics and the use of ammonium chloride as an extraction agent proved to be particularly effective for biogas upgrading to biomethane level. In contrast, both the absorption and reaction temperature, as well as gas-specific influencing factors such as carbon dioxide concentration and volume flow rate, had little to no influence. With regard to ash quality, an improvement of the landfill class from IV to 0 was achieved with respect to lead, from II to 0 for zinc and from III to I for cadmium. A significant improvement was also achieved for chlorine, but this did not result in a reduction of the landfill class. The ash quantity could be reduced by more than 50 %, among other things, by dissolving out the alkaline earth metals for the carbon dioxide reaction. As further research steps, it remains to further reduce the metal mobility with respect to the ash eluate in order to better optimize the process water quality. This could be achieved, for example, by a controlled pH value.