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L’attaque sulfatique externe est un processus de dégradation au cours duquel les propriétés mécaniques et la composition chimique d’un matériau cimentaire vont être fortement affectées par la pénétration de sulfates en solution. La réponse à ce problème repose en partie sur la maîtrise de la composition des ciments. A ce titre, la capacité d’un ciment CEM I à former de l’ettringite lors de l’ASE et donc, par extension, d’être considéré comme résistant ou pas face aux sulfates, peut être évaluée par la formule de Sadran qui prend en compte les taux du C3A et C3S. Nous avons mis en place une méthode de caractérisation pour analyser le comportement de ciments CEM I de différents indices de Sadran. L’analyse s’appuie sur une méthodologie permettant une caractérisation globale de la dégradation. La teneur en C3A plus que l’indice de Sadran détermine le type de dégradation d’un ciment. La méthode de suivi et d’analyse utilisée sur les CEM I a été appliquée pour l’étude de ciments composés CEM V afin de comparer leur comportement avec celui de ciments résistants aux sulfates. Un essai incluant un pré conditionnement thermique, pour l’accélération de la dégradation, a été choisi et les résultats obtenus ont été comparés à ceux de l’essai développé précédemment au GeM. Il a été démontré que le pré conditionnement thermique ne permet pas une accélération significative de la dégradation. De plus, le séchage mis en place modifie la microstructure des échantillons de mortiers CEM V ; il ralentit la progression des sulfates et donc allonge le temps de réponse. L’adsorption des sulfates par les C-S-H fait l’objet de la dernière partie de cette thèse, tout en ouvrant sur des perspectives. / During external sulphate attack the mechanical properties and the chemical composition of a cementitious material are strongly affected by the penetration of sulphate in solution. The answer to this problem lies partly in the control of the composition of the cements. The ability of CEM I cements to form ettringite during external sulfate attack and therefore to be considered resistant, or not, to sulphates, can be evaluated by the formula of Sadran which considers the rates of C3A and C3S. We set up a characterization method to analyze the behavior of CEM I cements with different Sadran indexes. Two degradation mechanisms were observed, marked by either expansive phase precipitation or leaching. The monitoring and analysis method used on the CEM I cements has been applied to the study of CEM V blended cements in order to compare their behavior with that of sulphate resistant cements. A test including a thermal pre-conditioning was chosen and the results obtained were compared with those of the test previously developed at GeM. It has been shown that thermal pre-conditioning does not allow a significant acceleration of degradation. The adsorption of sulphates by C-S-H, as well as the loss of calcium, is the subject of the last part of this thesis, while opening up perspectives. The first results showed that sulphate fixation by C-S-H increases with the concentration of the sulphate solution.

Orientador: Ana Julia Fernandes / Resumo: Atividades portuárias são consideradas fontes de contaminação por metais, que em altas concentrações são tóxicos aos microrganismos, podendo mudar o tamanho, a composição e a atividade da comunidade microbiana. Essa pressão seletiva faz com que bactérias desenvolvam mecanismos para combater o estresse causado por eles. Diversos grupos de microrganismos que desenvolvem sistemas de tolerância a metais podem fazer sua biorremediação. Bactérias redutoras de sulfato (BRS) podem, devido ao seu metabolismo, precipitar metais facilitando sua remoção. A hipótese é que em áreas portuárias exista uma alteração na comunidade microbiana onde são favorecidos microrganismos resistentes, aumentando a chance do isolamento de bactérias resistentes com potencial biotecnológico. Portanto o objetivo dessa tese foi avaliar a influência da contaminação de metais na comunidade microbiana em áreas portuárias e na seleção de cepas resistentes, e isolar cepas de BRS com potencial biotecnológico. Para isso, foram coletados sedimentos de 2 áreas portuárias (Santos e São Sebastião) e uma área pristina (Ubatuba). Foram caracterizadas variáveis ambientais do sedimento (como pH, salinidade, temperatura, oxigênio dissolvido, porcentagem de matéria orgânica, concentrações de Cr, Cu, Cd e Zn). Foi extraído DNA total do sedimento para caracterização da comunidade utilizando sequenciamento Mi-Seq. Os sedimentos serviram como inóculo para isolamento de cepas que foram submetidas a testes de resistência aos metais.... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Port activities are considered sources of metal contamination, which in high concentrations are toxic to microorganisms, and can change the size, composition and activity of the microbial community. This selective pressure forces bacteria to develop resistance mechanisms. Several microorganisms groups that develop metal tolerance systems can perform their bioremediation. One example is Sulfate-reducing bacteria (SRB). Because of their metabolism, this group can precipitate metals facilitating their removal. In this way, the hypothesis is that in port areas there is a change in the microbial community where resistant microorganisms are favored, increasing the chance of isolation of resistant bacteria with biotechnological potential. Therefore, the objective of this thesis was evaluate the influence of metal contamination in the microbial community in port areas and in the selection of resistant strains, and to isolate strains of SRB with biotechnological potential. For this, sediments were collected from two port areas (Santos and São Sebastião) and one pristine area (Ubatuba). Sediment environmental variables were characterized (such as pH, salinity, temperature, dissolved oxygen, percentage of organic matter, concentrations of Cr, Cu, Cd and Zn). Total DNA was extracted from the sediment for community characterization using Mi-Seq sequencing. The sediments was used as inoculum for strain isolation, and the metal resistance was checked. The most contaminated sediments also wa... (Complete abstract click electronic access below) / Doutor

Acid sulfate (AS) soils are characterized by a large pool of sulfates which may provide significant amounts of acidity and heavy metals – commonly nickel (Ni), Cobolt (Co), Zinc (Zn) and Arsenic (As) - to surrounding surface waters. The occurrence of AS soils is widespread, covering 17 million ha globally, and they are known for threatening freshwaters in Australia, North America as well as in many tropical regions. Mobilization of mercury (Hg) from AS soils is however poorly studied and could potentially be an environmental problem of concern due to its toxicity and capacity of bioaccumulating in food webs. In this study I investigated whether Hg is mobilized from AS soils by conducting chemical analyses on sediment samples from a 1,6 m deep lake core and a transect of surficial sediment samples in an adjacent sea bay. Here, I used zircon (Zr) and zinc (Zn) as proxies for silicate sources and sulfide soil sources, respectively. I found that Zn and Hg concentrations normalized to the organic matter content (LOI) showed a significant correlation in the lake core; hence, Hg in the sediment co-varied with my sulfide proxy and showed no correlation to my silicate proxy, and I then conclude that a considerable fraction of mercury in the studied sediment has a likely origin from AS soils.

Deep-sea anoxic brine pools are one of the most extreme ecosystems on Earth, which are characterized by drastic changes in salinity, temperature, and oxygen concentration. The interface between the brine and overlaying seawater represents a boundary of oxic-anoxic layer and a steep gradient of redox potential that would initiate favorable conditions for divergent metabolic activities, mainly methanogenesis and sulfate reduction. This study aimed to investigate the diversity of Bacteria, particularly sulfate-reducing communities, and their ecological roles in the interfaces of five geochemically distinct brine pools in the Red Sea. Performing a comprehensive study would enable us to understand the significant role of the microbial groups in local geochemical cycles. Therefore, we combined culture-dependent approach and molecular methods, such as 454 pyrosequencing of 16S rRNA gene, phylogenetic analysis of functional marker gene encoding for the alpha subunits of dissimilatory sulfite reductase (dsrA), and single-cell genomic analysis to address these issues. Community analysis based on 16S rRNA gene sequences demonstrated high bacterial diversity and domination of Bacteria over Archaea in most locations. In the hot and multilayered Atlantis II Deep, the bacterial communities were stratified and hardly overlapped. Meanwhile in the colder brine pools, sulfatereducing Deltaproteobacteria were the most prominent bacterial groups inhabiting the interfaces. Corresponding to the bacterial community profile, the analysis of dsrA gene sequences revealed collectively high diversity of sulfate-reducing communities. Desulfatiglans-like dsrA was the prevalent group and conserved across the Red Sea brine pools. In addition to the molecular studies, more than thirty bacterial strains were successfully isolated and remarkably were found to be cytotoxic against the cancer cell lines. However, none of them were sulfate reducers. Thus, a single-cell genomic analysis was used to study the metabolism of uncultured phyla without having them in culture. We analysed ten single-cell amplified genomes (SAGs) of the uncultivated euryarchaeal Marine Benthic Group E (MBGE), which contain a key enzyme for sulfate reduction. The results showed the possibility of MBGE to grow autotrophically only with carbon dioxide and hydrogen. In the absence of adenosine 5’-phosphosulfate reductase, we hypothesized that MBGE perform sulfite reduction rather than sulfate reduction to conserve energy.

Proteomic techniques were used to analyze the protein profile of earthworm, Lumbricus terrestris, coelomic fluid collected by either whole body dissection method or the coelomic cavity puncture method. Data demonstrated that collection of coelomic fluid using the coelomic cavity puncture method protocol resulted in a 32% reduction, 377 +/- 4.5 vs 253+/- 19.9 (p=0.0007), in the number of individual proteins. It was determined that the coelomic cavity puncture method yielded a "cleaner" preparation, one less contaminated with extraneous proteins from intestinal tissue, gut contents, and body wall materials. This protocol was used in all later studies. The same proteomic techniques were used to evaluate the effects that exposure to Cu (1.0 μg/cm2) as CuSO4 had on the earthworm coelomic fluid profile. Comparison of protein profile from exposed earthworms demonstrated a significant reduction in the number of proteins expressed (184 ± 2.64 vs 253 ±19.9 p=0.0192) when compared to control organisms. Cu exposure also resulted in a modulation of the protein profile with treated earthworms expressing 47 new proteins that were not identified in unexposed worm coelomic fluid. Additionally, 116 proteins found in coelomic fluid collected from normal worms were absent in Cu exposed organisms. Finally, 137 proteins were conserved or found in both control and exposed organisms; however of these proteins, 24 were up-regulated, 105 were down-regulated, and 8 were unchanged as a result of Cu exposure.

The leakages of metals from acid sulfate soils and their potential toxicity to benthic invertebrates were studied in the sediment profiles of Lillkvasjön and Lövselefjärden - a lake and an estuary known to be affected by acid sulfate soils - in Västerbotten, northern Sweden. The concentrations of 25 different elements were analyzed throughout both sediment profiles through X-Ray Fluorescence (XRF) Spectrometer analysis. Organic matter was measured through loss-on-ignition (LOI). By performing correlation analysis and normalizations to LOI on all sediment variables, Cu, Fe, Ni, Pb, S and Zn were found to be leached from acid sulfate soils to both sites, while Mg and Mn were related to leakages from acid sulfate soils in Lövselefjärden. The concentrations of Cu (195 mg kg-1), Ni (55 mg kg-1), Pb (90 mg kg-1) and Zn (398 mg kg-1) in the surface sediment of Lövselefjärden were classified as potentially toxic to benthic invertebrates. In Lillkvasjön, Cu (210 mg kg-1) and Ni (87 mg kg-1) were classified to have an increased risk of negative impacts on benthic invertebrates, while the concentrations of Pb (121 mg kg-1) and Zn (329 mg kg-1) were likely to low to have any negative effects. These results strengthen previous finds of impacts from acid sulfate soils in the two catchment areas and elucidate the importance of further studies on the impact of acid sulfate soils on benthic invertebrates.

Activated carbon is a highly adsorbing material and has various scopes of uses depending on needs. It is used in many industries and applications e.g. to clean industrial wastewater, in medicine, discolor sugar and so on. What makes AC such a good adsorbent is its porous structure which gives it a high surface area.  This report consists of three parts; general information about Activated Carbon (AC) and its characteristics, to give the reader a sufficient background about AC for continuous understanding throughout the report, an experimental investigation in chemical activation of carbon with phosphoric acid as the chemical reagent and sawdust from both Cuban and Swedish Pine tree as precursors, and a second experimental investigation in chemical activation of carbon with Zinc Sulfate as the chemical reagent and sawdust from Cuban Pine tree as the precursor. For the first experimental part as well as for the second the objective is how to best combine the three parameters; acid concentration, impregnation ratio and activation temperature in order to get the best adsorption performance when preparing activated carbon with different precursor specimens and chemical reagents. The experiments with phosphoric acid activation show that treatment with 40% acid concentration at 400 °C produce an activated carbon with good properties for ammonia adsorption and good iodine number. If a 30% phosphoric acid is used for activation, an activation temperature of 500 °C is recommended. With an impregnation ratio of 1, good adsorption was obtained in the activated carbon produced from Swedish pine while using Cuban pine a higher adsorption was obtained with an impregnation ratio of 2. The experiments with Zinc Sulfate activation show that influence of the sulfate concentration (between 10 % and 40 %) and temperature (between 400 °C and 500°C) on the properties for ammonia adsorption in the produced activated carbon was considerable for low impregnation ratio (0.5 and 1). In general, activation conditions of 20% zinc sulfate concentration, 400 °C and impregnation ratio: 1 are enough to produce an activated carbon with good properties for ammonia adsorption. The adsorption of carbon tetrachloride was lower. Activated carbons produced with 10 % zinc sulfate concentration, 0.5 impregnation ratio and 400 °C activation temperature (the mildest studied conditions) show already good iodine number and BET surface area.  The main conclusion from the thesis work is that the optimal conditions vary widely with wanted results. Therefore a suggestion for future work is to narrow the research to fewer variables and more repetition of the samples.

The study employed multi-variate methods to generate vulnerability maps for acid sulfate soils (AS) in the Norrbotten county of Sweden. In this study, the relationships between the reclassified datasets and each biogeochemical element was carefully evaluated with ANOVA Kruskal Wallis and PLS analysis. The sta-tistical results of ANOVA Kruskall-Wallis provided us a useful knowledge of the relationships of the preliminary vulnerability ranks in the classified datasets ver-sus the amount of each biogeochemical element. Then, the statistical knowledge and expert knowledge were used to generate the final vulnerability ranks of AS soils in the classified datasets which were the input independent variables in PLS analyses. The results of Kruskal-Wallis one way ANOVA and PLS analyses showed a strong correlation of the higher levels total Cu2+, Ni2+ and S to the higher vulnerability ranks in the classified datasets. Hence, total Cu2+, Ni2+ and S were chosen as the dependent variables for further PLS analyses. In particular, the Variable Importance in the Projection (VIP) value of each classified dataset was standardized to generate its weight. Vulnerability map of AS soil was a result of a lineal combination of the standardized values in the classified dataset and its weight. Seven weight sets were formed from either uni-variate or multi-variate PLS analyses. Accuracy tests were done by testing the classification of measured pH values of 74 soil profiles with different vulnerability maps and evaluating the areas that were not the AS soil within the groups of medium to high AS soil probability in the land-cover and soil-type datasets. In comparison to the other weight sets, the weight set of multi-variate PLS analysis of the matrix of total Ni2+& S or total Cu2+& S had the robust predictive performance. Sensitivity anal-ysis was done in the weight set of total Ni2+& S, and the results of sensitivity analyses showed that the availability of ditches, and the change in the terrain sur-faces, the altitude level, and the slope had a high influence to the vulnerability map of AS soils. The study showed that using multivariate analysis was a very good approach methodology for predicting the probability of acid sulfate soil.

Now when the interest is increasing to reach a sustainable infrastructure, one possibility SCA is experimenting with is the possibility to produce renewable hydrocarbons from black liquor which can be extracted from a Kraft process. However, when extracting the black liquor, a lot of sodium-based compounds are removed from the recovery process and when hydrocarbons are produced in SCA’s biorefinery, these compounds are caught in an aqueous solution. The aqueous solution is received at 50°C, and the sodium-based compounds are mainly sodium sulfate and sodium carbonate, where the solution do also contain organic compounds and a solvent that is used in the biorefinery.  This thesis focused on building a concept to extract sodium sulfate from the aqueous solution. The thesis did also include if any additional preparatory work needs to be done to the solution before extracting sodium sulfate. Finally, a flow chart that maps the energy needed for the process was created.  The method that was used was crystallisation by cooling the solution. By cooling the solution, sodium sulfates solubility decreases which will result in that sodium sulfate falls out of the solution as crystals. It was determined that the solvent that the solution contains should be extracted if the solvents boiling temperature is below 100°C. Further, by cooling the solution under stirring to 15°C with a residence time of 3 hours, unwanted compounds can be extracted. By later cooling the solution under stirring to 5°C with a residence time of 1 hour, it gave sodium sulfate decahydrate (Na2SO4·10H2O) with small amounts of organic compounds. By removing the water, the dry product reached a purity of 94wt% sodium sulfate with a yield of 12% (mass of dry product/mass of aqueous solution). This result reached the specific objectives that were set at the start of this thesis, which was to reach a purity of 90wt% sodium sulfate with a yield of 5%.  The energy intensity for evaporating the solvent is expected to be high. It highly depends on which solvent is used. However, this process can use the lowest quality of steam that is available from the pulp mill. It is expected that the cooling will require high amounts of cooling water and a high investment cost for the heat exchanger. Yet, this is a vital part of the process to reduce the need for coolers which is powered by electricity. / Nu när intresset ökar, för att nå en hållbar infrastruktur, så experimenterat SCA med möjligheten att producera förnybara kolväten från svartlut som kan extraheras från en sulfatprocess. Vid extrahering av svartluten tas dock mycket natriumbaserade föreningar bort från återvinningsprocessen och när kolväten produceras i SCA:s bioraffinaderi fastnar dessa föreningar i en vattenlösning. Den lösningen tas emot vid 50°C och de natriumbaserade föreningarna är huvudsakligen natriumsulfat och natriumkarbonat, där lösningen också innehåller organiska föreningar och ett lösningsmedel som används i bioraffinaderiet. Denna avhandling fokuserade på att bygga ett koncept för att extrahera natriumsulfat från vattenlösningen. Avhandlingen omfattade också om ytterligare förberedande arbete måste göras av lösningen innan man extraherar natriumsulfat. Slutligen skapades ett flödesschema som kartlägger den energi som behövs för processen. Metoden som bestämde sig för att användas var kristallisering genom kylning av lösningen. Genom att kyla lösningen minskar lösligheten av natriumsulfater vilket leder till att natriumsulfat faller ut ur lösningen som kristaller. Det bestämdes att lösningsmedlet som lösningen innehåller skulle extraheras om lösningsmedlets koktemperatur är under 100°C. Vidare, genom att kyla lösningen under omrörning till 15°C med en uppehållstid på 3 timmar, kan oönskade ämnen extraheras. Genom att senare kyla lösningen under omrörning till 5°C med en uppehållstid på 1 timme gav natriumsulfatdekahydrat (Na2SO4·10H2O) med små mängder organiska föreningar. Genom att avlägsna vattnet nådde den torra produkten en renhet av 94 vikt% natriumsulfat med ett utbyte av 12% (massa torr produkt/massa vattenlösning). Detta resultat nådde de specifika mål som sattes i början av denna avhandling, vilket var att nå en renhet av 90 vikt% natriumsulfat med ett utbyte på 5%. Energiintensiteten för att förånga lösningsmedlet förväntas vara hög. Det beror mycket på vilket lösningsmedel som används. Denna process kan dock använda den lägsta ångkvaliteten som finns tillgänglig från massafabriken. Det förväntas att kylningen kommer att kräva stora mängder kylvatten och höga investeringskostnader för värmeväxlaren. Ändå är detta en viktig del av processen för att minska behovet av kylare som drivs av elektricitet.