Die am häufigsten für die Zerkleinerung des Zementklinkers eingesetzte Kugelmühle stellt eine relativ einfache Maschine dar, in der sehr komplizierte dynamische Wechselwirkungen herrschen. Die direkte Messung der Beanspruchungsintensitäten ist heutzutage immer noch eine schwierige Aufgabe. In der vorliegenden Arbeit sind die Spektren der Beanspruchungsgrößen sowie einige spezifische integrale Größen mit der Methode der diskreten Elemente (DEM) untersucht worden. Eine besondere Aufgabe bestand in der Ermittlung der Parameter des viskoelastischen Kontaktmodells und der den Zementklinker charakterisierenden mechanischen Größen. Die reale Abbildung der Stoßvorgänge wurde anhand vereinfachter Modelle der Messprüfstände validiert. Mit den ermittelten Parametern sind numerische Untersuchungen durchgeführt worden, mit denen ihre Auswirkung auf die Zielgrößen bestimmt wurde. In Hinsicht auf eine mögliche konstruktive Weiterentwicklung sind Simulationen mit festgelegten betrieblichen und zu variierenden konstruktiven Parametern durchgeführt worden.

The Master thesis deals with utilization possibilities of fly ash after selective non-catalytic reduction (SNCR) process for Portland cement preparation as a correction component to the raw material with regard to contaminated fly ash by ammonium sulphate or ammonium hydrogensulfate that is one of the products from SNCR process. Presented thesis was focused on behaviour of raw meal with ammonia hydrogensulfate contaminated fly ash after SNCR during burning of Portland clinker in simulated kiln conditions. The thesis deals with Portland clinker preparation from this kind of raw mix and it studies mainly clinker quality, clinker phases and structure. Quantitative phase composition of prepared samples of clinker was performed by optical microscopy measurements using point counting method and XRD analysis (Rietveld method). Hydration heat flow of prepared clinker was measured by Isothermal Calorimetry. TG-DTA analysis of prepared raw meal was studied due to better comparison of prepared samples and better understanding of processes during burning process.

Due to the increasing usage of Sn in different electronics, such as solders and in touchscreens, together with Boliden Rönnskärs increased intake of electronic waste as a secondaryraw material, a Zn-containing product called Zn-clinker has increasing amounts of Sn. TheZn-clinker is shipped to Boliden Zn-smelter in Odda, where the Zn-clinker is mixed in withcalcine (roasted concentrate) and leached in several steps. Since Zn-clinker is a product froma halogen removal in a clinker-furnace, the feed material (Mixed Oxide), for this furnace, wasalso investigated since there are plans to replace clinkering with soda-washing in the future.Most of the Sn ends up in the leaching residue which then is deposited in the mountaincaverns close by the Boliden Odda smelter. Boliden is studying the possibility to recoverPb/Ag and Sn content from the leaching residue and create a valuable by-product. Bystudying how the leaching of Sn behaves, together with a characterization of the materials, thefollowing question should be answered: “During which sulphuric acid leaching conditions, ofZn-clinker and Mixed Oxide, is the leaching of Sn minimized?” The leaching results for Zn-clinker showed that 8-10% Sn will leach out, despite changingtemperature, redox potential, time and pH. A characterization of the material with SEM-EDSand XRD-analysis was also conducted to see if Sn could be identified in any phases in thematerials. The studies provided enough evidence that Zn2SnO4 could be concluded to be themain phase in the leaching residue for Zn-clinker, a form that would not leach underconditions presented in this project. However, 8-10% of the Sn will come together with Feand when Fe leach out, so does Sn. The leaching results for Mixed Oxide pointed towards that different phases from them foundin Zn-clinker was present. Sn losses varied between 10-20% but raised to 47% whentemperature was changed to 80 °C during leaching. The SEM-EDS analysis showed that theidentified Sn-phases contained more Sn than in Zn-clinker and together with the leachingresults, a conclusion that Sn would mainly be found as SnO2 or SnO in the Mixed Oxide, butthere is still uncertainty about the distributions of these forms. Unfortunately half of the As leached out during the soda-washing for Mixed Oxide, creating aleachate with Cl, F and As that need to be taken care of. This could be challenging andpresenting a costly side-project for the route different from the Zn-clinker route used today.Another observation was that PbCO3 formed during the soda-washing, a phase that willconsume more sulphuric acid during leaching.

O projeto enfocou a aplicação da difração de raios-X (DRX) na caracterização e quantificação dos compostos cristalinos do clínquer de cimento Portland, através do método de Rietveld, constituindo-se em contribuição pioneira sobre o tema em âmbito nacional. Foram utilizadas 40 amostras de clínquer provenientes de cinco diferentes unidades fabris, visando ampla representatividade do material de estudo. O clínquer de cimento Portland é o material sinterizado e peletizado, resultante da calcinação de uma mistura adequada de calcário e argila e, eventualmente, de componentes corretivos. Os compostos metaestáveis do clínquer Portland podem ser subdivididos em três grupos distintos: os silicatos cálcicos (C3S e C2S), a fase intersticial (C4AF, C3A, C12A7), e o grupo dos componentes menos freqüentes como o periclásio, a cal livre e os sulfatos. As proporções destes compostos são parâmetros importantes no controle de processo industrial de clinquerização. O método de Rietveld tem por base a simulação de todo o perfil difratométrico a partir de parâmetros estruturais das fases constituintes, permitindo refinar parâmetros de natureza instrumental e cristalográfica. A comparação do difratograma calculado com o observado e redução das diferenças através do método de mínimos quadrados permitem a obtenção de resultados quantitativos. DRX-Rietveld apresentou-se como uma técnica de quantificação de elevada reprodutibilidade com vantagens de cunho técnico e logístico com relação aos dois métodos correntemente utilizados no Brasil (microscopia e cálculo potencial de Bogue). Técnicas analíticas adicionais permitiram comparar resultados quantitativos obtidos por DRX-Rietveld e também correlacionar características dos compostos com o seu perfil difratométrico. A microscopia óptica foi a técnica de maior importância para comparações tanto qualitativas como quantitativas. A microscopia eletrônica (MEV-EDS) permitiu a aferição de fases não identificadas por microscopia óptica, como o C12A7 e sulfatos. A técnica de dissolução seletiva, aplicada para a concentração da fase intersticial, deu suporte para a aferição quantitativa de teores de polimorfos do C3A. A técnica mostrou resultados coerentes com a microscopia e o cálculo potencial de Bogue, sendo que constituintes não quantificados nestes puderam ser introduzidos (C12A7 e sulfatos), bem como possibilitou a distinção entre polimorfos de um mesmo composto (C3A). A redução no tempo de análise e a diminuição da subjetividade das análises, face às metodologias usuais, constituem fatores importantes da técnica visando atender os interesses da indústria do cimento. / The project has focused on the application of X-ray diffraction (XRD) on the characterization and quantification of the Portland cement clinker crystalline compounds using the Rietveld method. The present research represents a pioneer scientific contribution on the theme in Brazil. Overall forty clinker samples from five distinct kiln lines were collected for analysis aiming to get a broad representativeness of various cement process parameters. Portland cement clinker is the sintered and pelletized product from calcination of an adequate mix of limestone and clay and minor corrective materials. The metastable Portland clinker compounds are subdivided into three main groups: calcium silicates (C3S and C2S), matrix (C4AF, C3A, C12A7) and minor components as periclase, free lime and sulfates. The proportioning of these phases are important parameters to the industry clinkering process. The Rietveld XRD method is based on the simulation of the whole diffraction spectrum from the components structural data, allowing for refining instrumental and crystallographic parameters. By comparing the calculated and actual diffractograms and minimizing differences mathematically through a least squares method quantitative values are obtained. The Rietveld XRD has shown to be a high reproducible quantification technique, with technical and logistics advantages in comparison to the more usual microscopy and Bogue potential calculation. Additional analytical techniques have given reference data to compare quantitative results obtained from Rietveld XRD and to correlate characteristics of the compounds with their diffractogram profile. Optical microscopy was the most relevant technique for comparison both qualitative and quantitatively. Scanning electronic microscopy - energy dispersive system has allowed recognition of phases that could not otherwise be identified by optical microscopy, like C12A7 and sulfates. Selective dissolution of silicates carried out in order to concentrate matrix compounds sustained the quantitative results of C3A polimorphs found by Rietveld XRD. Rietveld has shown coherent results with both microscopy and Bogue potential calculation, but additionnally made it possible quantifying other compounds like C12A7 and sulfates, as well as distinguishing C3A polimorphs. The significant time saving and subjectivity minimization it provides makes up key-factors for the cement industry needs.

DIPLOMA THESIS IS FOCUSED ON THE PREPARATION AND PROPERTIE OF BELITE CLINKER. IT IS BASED ON THE STUDY OF SCIENTIFIC ARTICLES DEALING WITH THE ABOVE MENTIONED TOPIC AS WELL AS THE ANALYSIS OF THE BRNO THD INSTITUTE´S RESEARCH RESULTS. AS PART OF MY EXPERIMENTAL WORK, A PROPOSAL OF THE COMPOSITION OF RAW MEAL TO EXTRACT BELITE CLINKER IN THE PRESENCE OF POTASSIUMS CARBONATE AND SULPHATE WAS MADE TO MODIFY RAW MEAL. THE PURPOSE OF MODIFYING RAW MEAL IS A POTENTIAL INCREASE IN BELITE CLINKER REACTIVITY. FURTHER THE EXTRACTION OF BYPASS DUST FROM A LOCAL CEMENT PLANT WAS CONDUCTED. THE EVALUATION OF THIS RESEARCH WAS MADE BY THE X-RAY DIFFRACTION (XRD) ANALYSIS METHOD.

The issue of Hexavalent chromium toxicity to Portland cement hydration is a very actual these days. It takes much effort to obtain a cement containing Cr(VI) less than 2 ppm. The primary objective of this diploma theses is to find appropriate reducing substances and specify their efficiency, as well as to make an attempt to optimize their dosage. As reducing substances there were plumbed sulphites and tin(II) salts. The influence of reducing substances applied to the hydration and cement properties were validated by strenght tests, the calorimetric measurement and the volume-variation measurement. And also the changes in hydration products microstructure of Portland clinker after the gypsum replacement by sulphite ions were plumbed. The study of microstructure is based on SEM and XRD methods.

This diploma thesis is focused on evaluation of the possibilities of using FBC ash for production of blended cement and monitoring the hydration process, specially creation of the AFt phases.

The Master’s thesis is focused on a study of the effect of increased content of heavy metals present in a raw meal on the formation and properties of prepared clinker and acquired cement. Main attention is devoted to changes on the physical, mechanical, microstructural and hydration properties. The theoretical part contains an overview of clinker minerals occurring in Portland cement including the possibility of incorporation of heavy metals into their structure and affecting the properities of the cement. In the experimental part, there is compared the effect of heavy metal oxides on the composition and hydration properties of portland clinker and physical-mechanical and microstructural properities of cement pastes prepared from this clinker.

The aim of this thesis is to summarize the knowledge gained in the field of grinding medium-hard and hard materials. Work has focused on examining the grindability of the material using available laboratory mill. The part of the work is subsequent optimization of the grinding process on the device and evaluation of the results.

Tillverkning av portlandklinker står för ungefär fem procent av världens totala koldioxidutsläpp. Det finns därför ett allmänt intresse att minska användandet av portlandklinker. Klinkern kan antingen ersättas av andra cementerande material, eller så kan nya cementsnåla recept utformas. I den här rapporten har två cement med inmald flygaska respektive slagg från Cementa AB undersökts. För att undersöka klinkerersättnings-materialens potential har tester för tryckhållfasthet, uttorkningskrympning, bindetid, värmeutveckling och arbetbarhet utförts. Resultaten visar att skillnaderna mellan försökscementen och byggcementet är så pass små att båda bör kunna användas som byggcement. Ytterligare har ultrafiller av kalksten använts som ersättare för att minska cementhalten i betongen. Det går lika bra att delvis ersätta försökscementen med ultrafiller som det gör för byggcementet. Med cementsnåla recept och större del ersättningsmaterial finns det stora möjligheter att spara på energi och miljö. Detta borde i framtiden kunna leda till ett bättre och mer miljövänligt byggmaterial. / Manufacture of clinker is responsible for about five percent of the total global carbon dioxide emissions. Therefore, there is a general interest in reducing the use of clinker. Clinker can either be replaced by other cementitious materials, or reduced by using lean-cement recipes. This report examines two experimental cements, one with fly ash and one with slag, developed by Cementa AB. To examine the potential of clinker replacement materials, tests for compressive strength, drying shrinkage, initial setting, heat generation and workability, were performed. The results show that the differences between the experimental cements and the reference are so small that both are useable as building cements. In addition, an ultrafine filler of limestone is used as a replacement material for further reduction of the clinker content in concrete. It was also found, that it is just as efficient to partly replace the experimental cements with ultrafine filler as in the reference cement. There are great opportunities to save energy and the environment impact with both clinker-saving cement recipes and with cement replacement materials. This should lead to a better, more environmentally friendly, building material in the future.