Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-12-04T21:25:51Z No. of bitstreams: 1 RisiaAmaralAraujo_DISSERT.pdf: 2557863 bytes, checksum: 4baf213fa34b97a66d06a88c3ede8281 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-12-11T16:50:53Z (GMT) No. of bitstreams: 1 RisiaAmaralAraujo_DISSERT.pdf: 2557863 bytes, checksum: 4baf213fa34b97a66d06a88c3ede8281 (MD5) / Made available in DSpace on 2017-12-11T16:50:53Z (GMT). No. of bitstreams: 1 RisiaAmaralAraujo_DISSERT.pdf: 2557863 bytes, checksum: 4baf213fa34b97a66d06a88c3ede8281 (MD5) Previous issue date: 2017-11-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A fabrica??o dos materiais de constru??o requer elevado disp?ndio de energia e extra??o de recursos naturais, o que implica na gera??o de impactos ambientais preocupantes, em fun??o da produ??o de res?duos gasosos e s?lidos, como tamb?m mudan?as desastrosas do meio ambiente. Nesse contexto, existe um inconveniente do uso de Cimento Portland, em raz?o do alto consumo energ?tico e emiss?o de di?xido de carbono provocado pela calcina??o da mat?ria prima. Outro material poluente ? o proveniente da ind?stria de cer?mica vermelha, o qual emite res?duos gasosos e ainda origina demasiado volume de res?duos s?lidos em virtude de falhas no processo produtivo. Por outro lado, na antiguidade, as argilas termicamente tratadas, inclusive na forma de tijolos cer?micos finamente mo?dos, foram amplamente utilizadas devido ?s reconhecidas propriedades hidr?ulicas que conferiam as argamassas de cal a?rea. Dessa forma, esse estudo pretende avaliar a influ?ncia do res?duo de cer?mica vermelha (RCV) oriundo de telhas nas propriedades de argamassas mistas, a fim de que possa ser dado um destino adequado a esse res?duo. O RCV ap?s cominu?do em part?culas menores que 0,036 mm, foi adicionado em substitui??o parcial ao cimento Portland no tra?o 1:1:6 (cimento: cal: areia) de argamassas mistas empregada em revestimentos de paredes e tetos. Inicialmente o res?duo foi caracterizado e sua atividade pozol?nica investigada por de meio ensaios mec?nicos, an?lises granulom?tricas, termogravim?tricas e microestruturais. O teor de substitui??o das argamassas foi variado em 0, 10, 20 e 30% e as respectivas propriedades no estado fresco (consist?ncia, densidade, teor de vazios e reten??o de ?gua) e no estado endurecido (absor??o de ?gua, densidade, resist?ncia ? tra??o na flex?o e ? compress?o, e m?dulo de elasticidade) foram avaliadas. Constatou-se que o RCV possui significativa quantidade de silicatos e aluminatos reativos, comprovadas pela expressiva atividade pozol?nica que foi identificada nas an?lises qu?micas e f?sicas e no ?ndice de desempenho mec?nico 11% superior ao de refer?ncia. J? na produ??o das argamassas de revestimento com RCV obteve-se uma melhoria na trabalhabilidade, comprovada pela otimiza??o das propriedades no estado fresco, obtidas entre os teores de substitui??o do cimento Portland. No estado endurecido, as propriedades f?sicas e mec?nicas das argamassas com RCV apresentaram-se equivalentes ? argamassa de refer?ncia para os tra?os com 20% e 30% de substitui??o e melhorias significantes para o tra?o com 10% de substitui??o do cimento Portland por RCV. Com isso, constata-se que o RCV apresenta caracter?sticas pozol?nicas que resulta na melhoria das propriedades da argamassa no estado fresco e endurecido, sendo o teor de 10% o mais indicado em virtude da otimiza??o das propriedades. / The manufacture of construction materials requires high energy expenditure and extraction of natural resources, which implies the generation of disturbing environmental impacts, due to the production of gaseous and solid residues, as well as disastrous changes of the environment. In this context, there is a drawback of the use of Portland cement, due to the high energy consumption and emission of carbon dioxide caused by the calcination of the raw material. Other polluting material is that of the red ceramic industry, which emits gaseous waste and still gives rise to too much solid waste due to failures in the production process. On the other hand, in ancient times, thermally treated clays, even in the form of finely ground ceramic bricks, were widely used because of the recognized hydraulic properties that conferred lime mortars. Thus, this study intends to evaluate the influence of the red ceramic residue (CVR) from tiles in the properties of mixed mortars, so that a suitable destination can be given to this residue. The RCV, after being comminuted in particles smaller than 0.036 mm, was added in partial replacement to Portland cement in the 1: 1: 6 (cement: lime: sand) of mixed mortars used in laying of walls and covering of walls and ceilings. Initially the residue was characterized and its pozzolanic activity was investigated by means of mechanical tests, grain size, thermogravimetric and microstructural analyzes. The substitution content of the mortars was varied in 0, 10, 20 and 30% and their properties in the dry state (consistency, density, voids content and water retention) and in the hardened state (water absorption, density, resistance to flexure and compression tensile strength, and modulus of elasticity) were evaluated. It was verified that the RCV has a significant amount of reactive silicates and aluminates, evidenced by the significant pozzolanic activity that was identified in the chemical and physical analyzes and in the mechanical performance index 11% higher than the reference value. In the production of mortars with RCV, an improvement in the workability demonstrated by the optimization of the fresh state properties obtained in the Portland cement substitution levels was obtained. In the hardened state the physical and mechanical properties of RCV mortars were equivalent to reference mortar for the traces with 20% and 30% substitution and significant improvements for the trait with 10% replacement of the Portland cement by RCV. With this, it is verified that the pozzolana obtained from the RCV is a potential Pozolana that results in the improvement of the properties of the mortar in the fresh and hardened state, being the content of 10% the most indicated due to the optimization of all the properties.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-06-02T19:15:13Z No. of bitstreams: 1 EvertonHenriqueAndradeDeAraujo_DISSERT.pdf: 3778917 bytes, checksum: 0afcf798e13e94301cdf0341c3e0e55d (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-06-05T19:24:51Z (GMT) No. of bitstreams: 1 EvertonHenriqueAndradeDeAraujo_DISSERT.pdf: 3778917 bytes, checksum: 0afcf798e13e94301cdf0341c3e0e55d (MD5) / Made available in DSpace on 2017-06-05T19:24:51Z (GMT). No. of bitstreams: 1 EvertonHenriqueAndradeDeAraujo_DISSERT.pdf: 3778917 bytes, checksum: 0afcf798e13e94301cdf0341c3e0e55d (MD5) Previous issue date: 2016-09-02 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Dentre os argilominerais largamente estudados e aplicados na grande ?rea dos materiais cer?micos e outras ?reas, a caulinita se destaca, devido as suas caracter?sticas e desempenho tecnol?gico. O Estado do Rio Grande do Norte, possui um grande potencial na explora??o deste mineral, onde a principal forma de extra??o ? a lavra. O caulim desta regi?o, caracteriza-se como de origem prim?ria interperizada, devido a sua forma??o e caracter?sticas locais, diferenciando-o dos caulins de outras regi?es. Para isso, o caulim obtido foi submetido a um tratamento t?rmico, onde foi constatada uma gradativa amorfiza??o da estrutura cristalina caracter?stica do material. Com a obten??o da forma amorfa em laborat?rio, tamb?m denominada metacaulinita, foi poss?vel a realiza??o de uma investiga??o sobre as caracter?sticas pozol?nicas frente a outro material j? consolidado no mercado. Dessa forma o objetivo deste trabalho ? investigar a amorfiza??o do caulim industrial, oriundo da regi?o pegmat?tica do Serid? do RN, e comparar a sua atividade pozol?nica com um metacaulim comercial amplamente utilizado. Para isto, foram usadas as t?cnicas de Fluoresc?ncia de raios X (FRX); Difra??o de raios X (DRX); An?lise Termogravim?trica (TG); An?lise T?rmica Diferencial (DTA); Microscopia Eletr?nica de Varredura (MEV); Granulometria a Laser; Massa Espec?fica e ?ndice de Atividade Pozol?nica com a Cal. Ap?s as caracteriza??es pode-se observar que o metacaulim oriundo da regi?o em estudo possui boas caracter?sticas qu?micas e mineral?gicas, com a obten??o de um bom grau de amorfiza??o em baixas temperaturas e distribui??o granulom?trica pr?xima do material comercial analisado. A partir do resultado da atividade pozol?nica, o metacaulim obtido em laborat?rio apresentou um grande potencial na forma??o das fases hidratadas, sendo de grande import?ncia na ?rea de cimenta??o, dentre outros. / Among the clay minerals widely studied and applied in the large area of ceramic materials and other areas, kaolinite stands out due to its characteristics and technological performance. The State of Rio Grande do Norte has great potential in the exploration of this mineral, where the main form of extraction is the mining. The kaolin of this region, is characterized as of primary interperizada origin, due to its formation and local characteristics, differentiating it of the Kaolins of other regions. For this, the obtained kaolin was submitted to a thermal treatment, where a was verified a gradual amorphization was found of the crystalline structure characteristic of the material. By obtaining the amorphous form in the laboratory, also called metacaulinite, it was possible to carry out an investigation on the pozolanic characteristics compared to other materials already consolidated in the market. Thus the objective of this work Is to investigate the amorphization of industrial kaolin, coming from the pegmatitic region of Serid? RN, and to compare its pozzolanic activity with a commercially used metakaolin. For this, we used the techniques of fluorescence X-ray (XRF); X-ray diffraction (XRD); Thermogravimetric Analysis (TG); Differential Thermal Analysis (DTA); Scanning Electron Microscopy (SEM); Laser Granulometry; Specific Mass and Pozzolanic Activity Index with Cal. After characterization, it can be observed that metakaolin from the study region It has good chemical and mineralogical characteristics, with a good degree of amorphization at low temperatures and distribution close to the commercial material analyzed. From the result of pozzolanic activity the metakaolin obtained in the laboratory, presented a great potential in the formation of the hydrated phases, being of great importance in the area of cementation, among others.

Made available in DSpace on 2014-12-17T14:08:56Z (GMT). No. of bitstreams: 1 LornnaLAG_DISSERT.pdf: 2131175 bytes, checksum: 63e4a76183bcbcfcae20c296d8b0364d (MD5) Previous issue date: 2014-01-31 / Cementing operation is one of the most important stages in the oil well drilling processes and has main function to form hydraulic seal between the various permeable zones traversed by the well. However, several problems may occur with the cement sheath, either during primary cementing or during the well production period. Cements low resistance can cause fissures in the cement sheath and compromise the mechanical integrity of the annular, resulting in contamination of groundwater and producing zones. Several researches show that biomass ash, in particular, those generated by the sugarcane industry have pozzolanic activity and can be added in the composition of the cementing slurries in diverse applications, providing improvements in mechanical properties, revenue and cement durability. Due to the importance of a low cost additive that increases the mechanical properties in a well cementing operations, this study aimed to potentiate the use of sugarcane bagasse ash as pozzolanic material, evaluate the mechanisms of action of this one on cement pastes properties and apply this material in systems slurries aimed to cementing a well with 800 m depth and geothermal gradient of 1.7 ?F/100 ft, as much primary cementing operations as squeeze. To do this, the ash beneficiation methods were realized through the processes of grinding, sifting and reburning (calcination) and then characterization by X-ray fluorescence, XRD, TG / DTG, specific surface area, particle size distribution by laser diffraction and mass specific. Moreover, the ash pozzolanic activity added to the cement at concentrations of 0%, 20% and 40% BWOC was evaluated by pozzolanic activity index with lime and with Portland cement. The evaluation of the pozzolanic activity by XRD, TG / DTG and compressive strength confirmed the ash reactivity and indicated that the addition of 20% in the composition of cement slurries produces improvement 34% in the mechanical properties of the slurry cured. Cement slurries properties evaluated by rheological measurements, fluid loss, free fluid, slurry sedimentation, thickening time and sonic strength (UCA) were satisfactory and showed the viability of using the sugarcane ash in cement slurries composition for well cementing / A opera??o de cimenta??o ? uma das etapas mais importantes no processo de perfura??o de po?os de petr?leo e tem a fun??o primordial de promover a veda??o hidr?ulica entre as diversas zonas perme?veis atravessadas pelo po?o. No entanto, v?rios problemas podem ocorrer com a bainha de cimento, seja durante a cimenta??o prim?ria ou no decorrer do per?odo produtivo do po?o. Cimentos de baixa resist?ncia podem causar trincas na bainha de cimento e comprometer a integridade mec?nica do anular, resultando em contamina??o de len??is fre?ticos e zonas produtoras. V?rias pesquisas comprovam que cinzas de biomassa, em particular, as geradas pela ind?stria sucroalcooleira apresentam atividade pozol?nica e podem ser adicionadas na composi??o das pastas cimentantes em diversas aplica??es, proporcionando benef?cios nas propriedades mec?nicas, no rendimento e na durabilidade do cimento. Dada a import?ncia de um aditivo de baixo custo e que aumenta as propriedades mec?nicas em uma opera??o de cimenta??o de po?os, este trabalho objetivou potencializar o uso da cinza de biomassa da cana-de-a??car (CBCC) como material pozol?nico, avaliar os mecanismos de atua??o desta nas propriedades de pastas de cimento e aplicar este material em sistemas de pastas destinadas ? cimenta??o de um po?o com 800 m de profundidade e gradiente geot?rmico de 1,7 ?F/100 p?s, tanto para as opera??es de cimenta??o prim?ria quanto corretiva (squeeze). Para isso, foram realizados m?todos de beneficiamento da cinza atrav?s dos processos de moagem, peneiramento e requeima (calcina??o) e, em seguida, a caracteriza??o por fluoresc?ncia de raios-X, DRX, TG/DTG, superf?cie espec?fica, granulometria a laser e massa espec?fica. Al?m disso, a atividade pozol?nica da cinza, adicionada ao cimento nas concentra??es de 0% (pasta padr?o), 20% e 40% BWOC, foi avaliada pelo ?ndice da atividade pozol?nica com a cal e com o cimento Portland. A avalia??o da atividade pozol?nica atrav?s das an?lises de DRX, TG/DTG e resist?ncia ? compress?o comprovaram a reatividade do material e indicaram que a adi??o de 20% de cinza na composi??o das pastas produz melhorias em at? 34% das propriedades mec?nicas da pasta endurecida. As propriedades das pastas avaliadas atrav?s dos ensaios de propriedades reol?gicas, perda de filtrado, ?gua livre, estabilidade, tempo de espessamento e resist?ncia ? compress?o (UCA) mostraram-se satisfat?rias e indicaram a viabilidade da utiliza??o da cinza na composi??o das pastas de cimento para po?os de petr?leo

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-06-14T19:53:37Z No. of bitstreams: 1 LechWalesaOliveiraSoares_DISSERT.pdf: 2473726 bytes, checksum: d7a80c7eeaba135cb9b0bb6355b7a8c2 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-06-15T23:04:07Z (GMT) No. of bitstreams: 1 LechWalesaOliveiraSoares_DISSERT.pdf: 2473726 bytes, checksum: d7a80c7eeaba135cb9b0bb6355b7a8c2 (MD5) / Made available in DSpace on 2016-06-15T23:04:07Z (GMT). No. of bitstreams: 1 LechWalesaOliveiraSoares_DISSERT.pdf: 2473726 bytes, checksum: d7a80c7eeaba135cb9b0bb6355b7a8c2 (MD5) Previous issue date: 2015-04-10 / A cimenta??o de po?os de petr?leo tem como fun??o b?sica promover a estabilidade mec?nica e selar hidraulicamente o po?o impedindo a comunica??o entre os diferentes tipos de fluidos. Materiais pozol?nicos s?o adicionados ao cimento, pois reagem com o hidr?xido de c?lcio formando silicatos e aluminatos de c?lcio hidratado, melhorando a estabilidade qu?mica dos produtos das fases hidratadas. A utiliza??o da cinza da casca de arroz, um rejeito da agroind?stria, na substitui??o parcial ou em adi??o ao cimento ? uma alternativa sustent?vel, na qual ? poss?vel reduzir os ?ndices de emiss?o de CO2 no processo de fabrica??o do cimento. Nesse trabalho foi avaliada a atividade pozol?nica da cinza da casca de arroz (RHA e WRHA) em pastas de cimento para po?os de petr?leo em adi??es de 10% e 20% com rela??o ? massa de cimento (BWOC). As pastas foram curadas por 28 dias a 38?C. As cinzas foram caracterizadas pelas t?cnicas de Microscopia Eletr?nica de Varredura (MEV), Infravermelho com Transformada de Fourier (FTIR), Energia Dispersiva de Raios X (EDX) e ?rea superficial (BET). A atividade pozol?nica foi avaliada pelas t?cnicas de An?lise Termogravim?trica (TGA), Difra??o de Raios X (DRX) e Resist?ncia ? Compress?o. Os resultados de TGA demonstraram que a adi??o da WRHA promoveu uma redu??o de aproximadamente 73% da fase Portlandita com rela??o ? pasta padr?o. A partir dos resultados de DRX foi poss?vel se evidenciou a redu??o da intensidade dos picos de Portlandita. Com base nos resultados apresentados podemos concluir que a cinza da casca do arroz reagiu quimicamente com a Portlandita produzindo C-S-H confirmando seu efeito como agente pozol?nico. / Pozzolanic materials such as rice husk ash are widely used to substitute part of cement, because they react with calcium hydroxide (CH) producing calcium silicate hydrate (C-S-H), which aggregate better physical, chemical and mechanical properties to the cement slurry. The usage of rice husk biomass ash from agribusiness in addition to or partially replacing cement is a noble purpose and a good way of sustainable development which currently is an obsession around the world. The ashes utilized in this study were characterized by: scanning electron microscopy technique (SEM), Fourier transform infrared spectroscopy (FTIR), Energy-dispersive X-ray spectroscopy (EDX) and BET method. The pozzolanic activity of RHA and WRHA in cement slurries was evaluated by: thermal-gravimetric technique and derivative thermogravimetry (TGA/DTG), X-ray diffraction (XRD) and Compressive Strength. The slurries formulated with additions of 10% and 20% of RHA and WRHA were cured for 28 days at 58 ?C. The results of thermal analysis demonstrated that a 20% WRHA addition caused a reduction of approximately 73% of Portlandite (calcium hydroxide ? CH) phase related to standard slurry (STD). The XRD scans also demonstrated the reduction of the Portlandite peaks? intensity for each slurry compared with STD slurry. The RHA and WRHA react chemically with Portlandite producing calcium silicate hydrate (C-S-H), confirming their effect as a pozzolanic agent. The WRHA presented the best results as a pozzolanic material.