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Este trabalho apresenta o desenvolvimento e a aplicação de um método alternativo para determinação de manganês em amostras de cimento e clínquer por voltametria de redissolução catódica por onda quadrada empregando eletrodos de ouro. Após estudos exploratórios acerca do comportamento eletroquímico do manganês no eletrólito suporte H3BO3 0,20 mol L-1 / KCl 0,10 mol L-1 com pH 6,5 e a otimização dos parâmetros operacionais para a voltametria de onda quadrada, foram obtidos excelentes resultados na determinação de manganês nas amostras analisadas. Destacam-se a ótima linearidade, verificada em duas faixas distintas de concentração, e os baixos limites de detecção e quantificação obtidos (3,1 x 10-8 mol L-1 e 9,8 x 10-8 mol L-1, respectivamente), além da concordância entre os resultados obtidos pela técnica eletroanalítica quando comparados aos resultados fornecidos pela espectrometria de absorção atômica de chama (FAAS). Para o tratamento das amostras foi avaliada a eficiência da extração ácida assistida por ultrassom. Foram avaliados ácidos minerais individualmente (HCl, H2SO4 e HClO4 em diferentes concentrações), em mistura ou ainda associados a H2O2. Os melhores resultados foram obtidos utilizando uma solução de HCl 3 mol L-1, que extraiu quantitativamente o manganês nas amostras analisadas. Os resultados obtidos foram concordantes com a metodologia padrão utilizada para a abertura da amostra e posterior análise por espectrometria de absorção atômica de chama, que emprega o aquecimento em chapa e a mesma solução extratora. / This work describes the development and application of a new alternative method for determination of manganese in cement and clinker samples by square wave cathodic stripping voltammetry using gold electrodes. After exploratory studies on the electrochemical behavior of manganese in H3BO3 0.20 mol L-1 / KCl 0.10 mol L-1 supporting electrolyte at pH 6.5 and the optimization of operating parameters for the square wave voltammetry, excellent results were obtained for determination of manganese in the samples analyzed. Most notable are the excellent linearity, verified in two distinct concentration bands and the low limits of detection and quantification obtained (3,1 x 10-8 mol L-1 e 9,8 x 10-8 mol L-1, respectively), in addiction to the concordance between the obtained results by the electroanalytical technique when compared to the provided by the flame atomic absorption spectrometry. For samples treatment were tested the efficiency of the ultrasound-assisted extraction. Were evaluated individually mineral acids (HCl, H2SO4 and HClO4 at different concentrations) in a mixture or associated with H2O2. the best results were obtained using a 3 mol L-1 HCl solution, which extracted manganese quantitatively from the analysed samples, in comparison to the standard method for extraction, targeting a later atomic absorption flame spectrometry analysis, which uses the plate heating and the same extracting solution. The obtained results for the analysed samples agrees with the cement and clinker samples of the used literature

Depuis la fin du 20ème siècle, notre société a pris conscience que la protection de l’environnement et le développement durable sont nécessaires à notre épanouissement futur. Des directives ont contraint les pouvoirs publics, les collectivités, ainsi que les industriels à réagir notamment en s’impliquant dans la recherche. Les cimentiers sont aussi concernés. La fabrication du ciment nécessite énormément de matières premières.L’objectif principal de cette thèse est donc de valoriser les sous-produits industriels en matériaux cimentaires. Le contexte et la problématique des déchets sont abordés, ainsi que la possibilité de valorisation par les ciments. La méthodologie mise en place et son originalité sont expliqués. Dans un premier temps, le protocole de caractérisation des déchets minéraux a été développé et les résultats en laboratoire sont prometteurs pour le remplacement du calcaire et de l’argile dans le cru d’un ciment. Les cuissons en laboratoire ont permis d’obtenir un ciment comportant les 4 phases d’un Portland. La synthèse en plus grande quantité d’une formulation en laboratoire a mis en évidence de bonnes performances mécaniques sur mortiers au jeune âge. Dans un deuxième temps, les meilleures formulations ont été testées à l’échelle industrielle, dans le four de ARF. Le cru, malaxé par trémies agitatrices, a été une réussite. Enfin, l’immobilisation des polluants dans une matrice cimentaire des résidus de combustion, provenant des combustibles secondaires de ARF a permis de déclasser le déchet stabilisé/solidifié par réduction granulométrique du matériau avant tabilisation/solidification. / Since 20th century’s end, our society started to take conscience of environmental protection and sustainable development are required to our future blooming. Directives have obliged public authorities, communities, such as industry to be reacted particularly while being implied in research. The cement-manufacturers are also concerned. The process cement-manufacturer requires large quantities of raw materials. The main objective of the thesis is to value industrial by-products by cementitious materials. Context and problem of wastes were discussed, as well as the possibility of valorization such as the cements. The methodology set up for the thesis and its originality are explained. First, the protocol of characterization of mineral wastes was developed. The results in laboratory are promising for the replacement of limestone and clay in the cement’s raw meal and different formulations. The cookings in laboratory allowed obtaining a cement containing 4 phases of Portland. The synthesis in bigger quantity of a formulation in laboratory highlighted good mechanical performances on mortars at the young age. In a second stage, the best formulations were tested on an industrial scale in the ARF’s kiln. The raw meal, mixed by hoppers agitators, was a success. Finally, immobilization of pollutants in a cement matrix of the residues after combustion, resulting from secondary fuels of ARF, was studied to be able to downgrade the waste stabilized/solidified by grading reduction of the material before stabilization/solidification.

The thesis is focused on the optimization of the thaumasite preparation in the way of ternesite hydration and further comparison of this approach to the other methods. The thaumasite was prepared by three different methods for this purpose - according to Aguilera et al., Purnell and the hydration method of ternesite clinkers. Finally, the X-ray diffraction analysis was particularly used to evaluate the obtained properties and results.

This work deals kinetics of grinding Portland cement clinker which is influenced by addition of grinding inlays surfactants. In an experiment, attritor-type stirred mill was used and surface active grinding additives such as polyethylenglykol (PEG), triethylamin (TEA) and acetate of ammonium were utilized. Granulometric distribution graph obtained from laser diffraction analysis provides data for plotting development diagrams for milling process.

This diploma thesis deals with the preparation binder systems based on Portland clinker and recycled brick. Recycled brick is considered a waste material from construction or production of brick products. This thesis uses finely grounded brick recycled and brick dust, which is produced during final processing of burnt bricks. By incorporating brick dust in alternative system based on Portland clinker could bring ecological and economic benefits. This diploma thesis deals with option using brick dust as pozzolan admixture to Portland clinker, with the aim to prepare and test Portland cement, which is defined in v ČSN EN 197-1. This thesis also deals with possibility preparation of alternative binders based on p-clinker, but those not defined by ČSN EN 197-1. Specifically these are ternary binders with fluid bed ash and binders based on hybrid cements containing sodium sulfate.

The dissertation thesis is devoted to the study of belite clinkers and to the possibilities of the increase in their hydraulic activity. The mechanism and the kinetics of belite clinker formation were studied together with the relation of the velocity of these processes and the hydraulic activity of clinker. The influence of various parameters (degree of lime saturation, duration and temperature of burning) of the belite clinker preparation on the belite clinker development in time, on belite polymorphism, on the chemical composition of belite crystals and on the belite cement hydraulic activity was studied, too. The research methods used for the investigation involved electron microscopy, optical microscopy, X-ray diffraction analysis, high-temperature microphotometry and calorimetry. The resulting clinkers were hydraulically activated by addition of calcium sulfate. The experiments have proven that the higher rate of belite formation does not lead to the increase of its hydraulic activity, as opposed to that of alite. On the other hand, the chemical activation by sulfate anions enables to prepare clinker with relatively higher degree of lime saturation with minor admixture of alite and anhydrite, which is hydraulically activated. The work was concluded by experimental burning of belite clinker doped with sulfate anions in a model rotary kiln and by the preparation of cements blended with common industrial alite clinker. The results indicate the possibility of separate industrial production of special belite clinker alongside with common alite clinker and the production of economically and environmentally beneficial blended Portland cements with suitable technological parameters, or targeted production of special cements with properties corresponding to their required utilization.

The report investigates the feasibility of accessing waste heat at kiln 7 in the Cementa AB cement plant in Slite, Gotland. The background is provided, with a description of the cement manufacturing process. Most of the report concerns itself with the heat transfer capabilities of the plant, therefore a short description of the heat flow within the most essential equipment is provided. The investigation follows a set of steps to derive the conclusion. The first step investigates previous studies to obtain the three most feasible heat sources. The second step investigates the available heat of the selected sources. In the third step, accessing the source is discussed and investigated for both convection and radiation heat transfer methods. It also includes the sizing of the required heat exchangers. Using the new sources, the connection possibilities to existing infrastructure and its benefits are investigated in step four. The connections were made to the existing infrastructure used at kiln 8 for electrical generation and district heating supply. The selections of the most feasible solutions are provided based on heat recovery, payback period and practicality. The final step in the study provides for the final design, which consists of three possible connections or all of them combined. In the conclusion, the final design would provide for a reduction in oil burned, fuel consumption and CO2 emissions and an increase in electricity generated by the existing system. It is recommended that only one of the three connections be installed. / <p>The thesis was conducted at Cementa AB in Slite, Gotland. The supervisor at the plant was Fred Grönwall.</p>

[pt] A indústria siderúrgica no Brasil gera atualmente cerca de 5 milhões de toneladas/ano de escória de aciaria LD. Estudos preliminares recentes têm mostrado ser promissora a produção de cimento mediante tratamentos térmicos e modificações químicas capazes de gerar fases com propriedades pozolânicas com resistência a compressão semelhantes às do cimento Portland. Dentro deste contexto o presente trabalho teve como objetivo investigar a viabilidade de utilização da escória LD na produção de um cimento Portland classe E por meio de ajuste químico composicional e tratamentos térmicos da escória ainda liquida utilizando análises químicas por ICP-OES e testes de resistência à compressão segundo a norma NBR 7215. Além disso, a presente pesquisa realizou estudo de correlação utilizando várias gamas de misturas e um fator de correlação entre os corpos de prova especificados pela norma (5x10cm) e corpos de prova menores (1x2cm), a fim de adequar um equipamento mais apropriado ao projeto. Os resultados mostraram que a mistura formada por 75 por cento Cimento Portland II F-32 e 25 por cento Novo Clínquer (escória de LD química e termicamente tratada) e a mistura com a relação 50-50 desses mesmos materiais, foram as que atenderam plenamente a condição exigida pela norma para a resistência à compressão dos Cimentos Portland Tipo II, Classe E, decorridos 28 dias de cura. Além disso os resultados mostraram viabilidade na correlação dos corpos de prova, dessa forma sendo possível a realização dos testes mecânicos com corpos de prova com dimensão de 1x2 cm. / [en] Nowadays the steel industry in Brazil generates about 5 million tons of LD steel slag annually. Recently some studies with its use in cement production have shown promise, once that after heat treatment and chemical modifications it can present phases with similar hydraulic properties to Portland cement and equivalent compressive strength as well. In this context, the present work aimed to investigate the feasibility of using LD slag for production of a Portland cement Class-E, in the face of chemical modifications of the liquid slag followed by a fast-cooling heat treatment and chemical analysis carried out by ICP-OES techniques and also a compressive strength test according to the NBR 7215 standard. In addition, based on the results of the compression test and to optimize the amount of material used, a correlation study was carried out between specimens in accordance with the standard (5X10cm) and smaller specimens (1X2cm), in order to use an appropriate lab compressive machine. The results showed that the mixtures using 75 percent Portland II Cement F-32 and 25 percent Novo Clinquer (chemical and heat-treated LD slag) and that one with 50-50 ratio using the same materials, were the mixtures that fully satisfied the minimum compressive resistance condition required by the NBR standard, concerning Type II Class Portland Cements, after 28 days of curing. In addition, the results showed feasibility in the correlation of specimens, thus making it possible to perform mechanical tests with specimens with a dimension of 1x2 cm.