In drilling technologies, Na-bentonite-water mixtures are used as drilling mud. As the reserves of sodium-bentonite decline, calcium or low-quality bentonites are activated with inorganic salts and/or treated with different types of polymers as an alternative to Na-bentonite. The quality of such bentonites, commonly referred to as extended bentonite may deteriorate under severe drilling conditions, such as / bacterial activity, high temperature etc. It was considered that borates could prevent the deterioration of extended bentonites due to their well known bactericide properties. This study involves the use of Na-Borate as an activating agent for bentonites in place of the commonly used Na-carbonate. The effects of Na-borate on the rheological and filtrate behaviours of two different bentonites, namely, Edirne Bentonite (E-Ben) and &Ccedil / ankiri Bentonite (C-Ben) were investigated. The results were evaluated based on API standards and in comparison to those of Na-carbonate activated bentonites. It was found that Na-borate could be used as a bentonite activator, although somewhat higher dosages (3,78% Na2O equivalent for E-Ben and 0,76% Na2O equivalent for C-Ben) than Na-carbonate (2,90% Na2O equivalent for E-Ben and 0,58% Na2O equivalent for C-Ben) are necessary to obtain the same rheological properties. In terms of aging, it was determined that aging had no adverse effect on v the rheological and filtrate properties of bentonite treated with carboxymethyl cellulose (CMC) and polyanionic cellulose (PAC), but rheological properties of bentonites treated with xanthan gum were found to deteriorate upon aging. The presence of Na-borate in the mud appears to alleviate this adverse effect.

Dissertação(mestrado)- Universidade Federal do Rio Grande, Programa de Pós-Graduação em Engenharia e Ciência de Alimentos, Escola de Química e Alimentos, 2009. / Submitted by Caroline Silva (krol_bilhar@hotmail.com) on 2012-08-23T22:39:00Z No. of bitstreams: 1 dissertao sidney fernandes bsandeira.pdf: 471235 bytes, checksum: 294665749b6914b1de32a76e8213e779 (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2012-08-27T17:36:42Z (GMT) No. of bitstreams: 1 dissertao sidney fernandes bsandeira.pdf: 471235 bytes, checksum: 294665749b6914b1de32a76e8213e779 (MD5) / Made available in DSpace on 2012-08-27T17:36:42Z (GMT). No. of bitstreams: 1 dissertao sidney fernandes bsandeira.pdf: 471235 bytes, checksum: 294665749b6914b1de32a76e8213e779 (MD5) Previous issue date: 2009 / A gelatina é o produto da hidrólise parcial do colágeno, contido em peles e ossos, e que pode ser obtida a partir de resíduos da industrialização de pescados. Assim, este trabalho teve como objetivo extrair e caracterizar gelatina de cabeças, provenientes da industrialização de carpas, da variedade cabeça grande (Aristichthys mobilis), e comparar as gelatinas obtidas das frações de peles/músculos e óssea das cabeças quanto às propriedades físicoquímicas e funcionais. As cabeças foram moídas e submetidas ao tratamento alcalino/ácido, em soluções de 3 M NaOH e 3 M HCl, respectivamente. A extração da gelatina em água (1:1 p/v) foi realizada a 52ºC por 2 h e pH 4. Após a centrifugação, separou-se a solução de gelatina do material sólido (ossos), que foi seco, moído, suspenso em 0,6 M HCl por 20 h a 10ºC, e posteriormente lavado com água. Foram realizadas quatro extrações dos ossos tratados, com adição de água (1:1 p/v) por 30 min, em pH e temperaturas de cada extração de 5,3 a 60ºC, 4,4 a 70ºC, 3,8 a 80ºC e 3,6 a 85ºC, respectivamente. O rendimento e o pH para a solução de gelatina obtida da fração de peles/músculos das cabeças, foram de 2 ggelatina/100 gamostra e 4,2, respectivamente. O rendimento da fração óssea foi de 4,1 ggelatina/100 gamostra com pH médio de 4,2. A força do gel (246 g), viscosidade (1,76 cP) e ponto de fusão (26,3ºC) da gelatina extraída da fração peles/músculos foram superiores as das gelatinas extraídas da fração óssea, que reduziram com o aumento da acidez e temperatura de extração. A capacidade de emulsificação (CE) e de formação de espuma (CFE) das soluções dos diferentes tipos de gelatina obtidas diminuíram com o aumento da temperatura de extração. / Gelatin is a product by partial hydrolysis of collagen, contained in skins and bones, which can be obtained from the industrialization of fish waste. Therefore, this study aimed to extract gelatins from heads of bighead carp (Aristichthys mobilis), and to determine their physicochemical characteristics. The heads minced were subjected to treatment alkaline/acid, in solutions of 3 M NaOH and 3 M HCl, respectively. Gelatin was extracted in water (1:1 w / v) at 52ºC for 2 h and pH 4. After centrifugation, the extract was separated from solid material (bones), which was dried, grinded, suspended in 0.6 M HCl for 20 h at 10ºC, and then washed with water. Gelatin was extracted from the bones treated in four steps, with the addition of water (1:1 w / v), stirring for 30 min in pH and temperature of each extraction from 5.3 to 60ºC, 4.4 to 70°C, 3.8 to 80°C and 3.6 to 85°C; respectively. The yield and pH for the gelatin solution of obtained from the skin fraction of the head, were 2.0 (ggelatin/100 gsample) and 4.15, respectively. The yield for bone fraction was 4.1 (ggelatin/100 gsample) with average pH of 4.17. The gel strength (246 g), viscosity (1.76 cP) and melting point (26.3ºC) of gelatin extracted from skins fraction, were higher than those of gelatin extracted from the bone fraction, which decreased with the increasing acidity and temperature of extraction. Emulsion activity (CE) and foam expansion (CFE) of gelatin obtained decreased, with increasing extraction temperature.

Made available in DSpace on 2014-12-17T15:01:19Z (GMT). No. of bitstreams: 1 MiguelASN.pdf: 491289 bytes, checksum: be60500500779f6a3fd87b90108feb8c (MD5) Previous issue date: 2002-09-27 / The developments in formulating drilling fluids to apply in petroleum fields are based on new technologies and environmental challenges, where the technical performance of a developed drilling fluid is used to produce a minimum environmental impact, showing great economy in costs. It is well known that the potential use of oil-based drilling fluids is limited because these fluids when discharged in the sea do not disperse as much as water-based ones and may form waterproof films in the seabed, having a profound effect on plants and animals living in this environment. The current works have been made in investigating fluids called pseudofluids, which are synthetic ester-based, n-paraffin-based and other fluids formed from inverse emulsion. In this research the principal parameters involved in inverse emulsion process were studied, in laboratory scale, using esters as main component. Others commercial drilling fluids were used as comparative samples, as well as samples from laboratory and field where these drilling fluids are being applied. Concentrations of emulsifier and organophilic clay, which are viscosity donor, were varied to verify the influence of these parameters, in different oil/water ratios (55/45, 60/40, 65/35, 70/30, and 75/25). The salt concentration (NaCl) is an indicative parameter of stability and activity of an esterbased fluid. In this research the salt concentration was varied in 10,000, 20,000, and 50,000 ppm of NaCl. Some rheological properties of the produced fluids were studied, such as: initial gel, plastic viscosity, yield point, and apparent viscosity. Through the obtained rheological measures, the existence of two systems could be verified: fluid and flocculated. It could be noticed that the systems were influenced, directly, by the oil/water ratio and emulsifier, organophilic clay and NaCl concentrations. This study showed the viability to use an ester obtained from a regional vegetable product baba?u coconut oil to obtain an efficient and environmental safe drilling fluid / O desenvolvimento atual e futuro, em campos de petr?leo, baseia-se em novas tecnologias e desafios ao meio ambiente, onde se utiliza principalmente a performance t?cnica de um fluido de perfura??o que produza o m?nimo impacto ambiental, mostrando ainda, uma ?tima economia nos custos desses desenvolvimentos. Sabe-se que o potencial de continuidade de fluidos de perfura??o a base de ?leo est? limitado e, por conseguinte, o avan?o ambiental tem sido na investiga??o de fluidos chamados pseudo-fluidos, ou seja, fluidos sint?ticos base ?ster, ?ster, n-parafina e outros fluidos de emuls?o inversa, os quais est?o em estudo. Neste trabalho estudou-se em n?vel de laborat?rio as principais vari?veis envolvidas no processo de emuls?o inversa usando ?steres como componente principal, utilizando-se amostras comparativas de outros fabricantes, como tamb?m amostras provenientes de laborat?rio e de campo onde est?o sendo utilizados estes fluidos de perfura??o. As concentra??es de emulsificante ou argila organof?lica, que ? doadora de viscosidade, foram variadas para verificar a influ?ncia destes par?metros a diferentes raz?es ?leo/?gua (55/45, 60/40, 65/35, 70/30 e 75/25), mantendo-se constante os demais componentes do fluido. A concentra??o do sal, que ? um par?metro indicador de estabilidade e da atividade em fluido a base ?ster, foi variada em 10.000, 20.000 e 50.000 ppm de NaCl. Algumas propriedades reol?gicas dos fluidos assim produzidos foram estudadas, tais como: gel inicial, viscosidade pl?stica, limite de escoamento e viscosidade aparente. A partir das medidas reol?gicas obtidas, p?de-se verificar a exist?ncia de dois sistemas: fluido e floculado. P?de-se perceber que os resultados obtidos foram influenciados diretamente pela raz?o ?leo/?gua e pelas concentra??es do emulsificante, da argila organof?lica e do NaCl. Este estudo consolidou importantes conhecimentos que abrir?o portas para o sucesso de novas pesquisas, tornando-se fundamental a viabiliza??o de coloc?-lo posteriormente no mercado de trabalho do Brasil