Spelling suggestions: "subject:"[een] DRILLING FLUIDS"" "subject:"[enn] DRILLING FLUIDS""
1 |
Solids transport in complex annular geometriesFord, John T. January 1997 (has links)
No description available.
|
2 |
Interactions at the clay/polymer/water interfaceShewring, Nigel Ivor Edward January 1998 (has links)
The thesis investigates the behaviour of aqueous montmorillonite suspensions and also the interactions between montmorillonite as a free standing film and in highly dispersed aqueous suspension with water soluble polymers used as additives in water based drilling fluids. FTIR microscopy and FTIR ATR spectroscopy have been employed to study in-situ dehydration of fully dispersed aqueous montmorillonite suspensions. The IR spectrum of the dispersed bentonite shows significant differences from that of a dry bentonite powder, which have been attributed to the hydration of the exchangeable cation. Drying, or concentrated salt solution causes the differences to disappear and this is attributed to the exchangeable cation settling back to its ditrigonal cavity in the silicate sheet of the mineral under these conditions. The adsorption of various molecular weights of neutral polyacrylamide (PAM) onto montmorillonite has been studied using FTIR transmission, ATR spectroscopy and XRD. Shifts seen in the NH[2] stretching and bending bands have been interpreted as being due to H-bonding with the outer co-ordination sphere of exchangeable cations. KCl has shown to have some influence on this system. Another neutral polymer used extensively in water based drilling fluids is polyalkylglycol (PAG). The adsorption of two molecular weights of this polymer from aqueous solutions of various concentrations have been monitored both in the presence and absence of KCl. The physical form of the montmorillonite (either as a free standing film or as a dispersed suspension), the concentration of the polymer solution, the polymer molecular weight and the presence of KCl all have significant effects on the adsorption of polymer. The stabilisation of montmorillonite films by PAG and PAG/KCl solutions has been monitored by ATR spectroscopy, and the dehydration of these films by polymer has been monitored using FTIR spectroscopy and XRD. The interaction of PAG is thought to be via hydrogen bonding with the innermost co-ordination sphere of the exchangeable cations which thus presents a hydrophobic surface to solvent molecules, preventing the film from collapse. Since all water based drilling fluids are multi-component systems, techniques previously used have been employed to study the competitive adsorption of the polyalkylglycol and polyacrylamide components. Preferential adsorption of the PAG is seen in these systems either due to the mass transport effects (PAG is considerably smaller than PAM) or due to PAG removing all but the inner cation hydration sphere, and presenting a hydrophobic surface for the PAM, and therefore preventing its adsorption.
|
3 |
Investigation on the effects of ultra-high pressure and temperature on the rheological properties of oil-based drilling fluidsIbeh, Chijioke Stanley 15 May 2009 (has links)
Designing a fit-for-purpose drilling fluid for high-pressure, high-temperature (HP/HT)
operations is one of the greatest technological challenges facing the oil and gas industry
today. Typically, a drilling fluid is subjected to increasing temperature and pressure with
depth. While higher temperature decreases the drilling fluid’s viscosity due to thermal
expansion, increased pressure increases its viscosity by compression. Under these
extreme conditions, well control issues become more complicated and can easily be
masked by methane and hydrogen sulfide solubility in oil-base fluids frequently used in
HP/HT operations. Also current logging tools are at best not reliable since the
anticipated bottom-hole temperature is often well above their operating limit. The
Literature shows limited experimental data on drilling fluid properties beyond 350°F and
20,000 psig. The practice of extrapolation of fluid properties at some moderate level to
extreme-HP/HT (XHP/HT) conditions is obsolete and could result in significant
inaccuracies in hydraulics models.
This research is focused on developing a methodology for testing drilling fluids at
XHP/HT conditions using an automated viscometer. This state-of-the-art viscometer is
capable of accurately measuring drilling fluids properties up to 600°F and 40,000 psig. A
series of factorial experiments were performed on typical XHP/HT oil-based drilling
fluids to investigate their change in rheology at these extreme conditions (200 to 600°F and 15,000 to 40,000 psig). Detailed statistical analyses involving: analysis of variance,
hypothesis testing, evaluation of residuals and multiple linear regression are
implemented using data from the laboratory experiments.
I have developed the FluidStats program as an effective statistical tool for characterizing
drilling fluids at XHP/HT conditions using factorial experiments. Results from the
experiments show that different drilling fluids disintegrate at different temperatures
depending on their composition (i.e. weighting agent, additives, oil/water ratio etc). The
combined pressure-temperature effect on viscosity is complex. At high thresholds, the
temperature effect is observed to be more dominant while the pressure effect is more
pronounced at low temperatures.
This research is vital because statistics show that well control incident rates for non-
HP/HT wells range between 4% to 5% whereas for HP/HT wells, it is as high as 100%
to 200%. It is pertinent to note that over 50% of the world’s proven oil and gas reserves
lie below 14,000 ft subsea according to the Minerals Management Service (MMS). Thus
drilling in HP/HT environment is fast becoming a common place especially in the Gulf
of Mexico (GOM) where HP/HT resistant drilling fluids are increasingly being used to
ensure safe and successful operations.
|
4 |
Development of Self-destructing Filter CakeRostami, Ameneh 2010 August 1900 (has links)
The main goal of drilling a horizontal well is to enhance productivity or injectory by placing a long distance drain-hole within the pay-zone. Poor drilling fluid design results in difficulties such as poor hole cleaning, excessive torque or drag, wellbore instability, stuck drill string, loss of circulation, subsurface pressure control, poor cement jobs, and difficulties associated with running electric logs and formation damage can result. Neither of the conventional chemical cleaning methods can overcome problems for filter-cake removal in long horizontal and maximum reservoir contact wells because of limitations such as the complex geometry of wells, non-uniform chemical distribution, low contact between cleaning fluids/filter cake, and high chemical reaction rate, especially at high temperatures.
This study describes a novel self-destructing drilling fluid system. Filter cakes are formed from a formula of drilling fluid that have a mixture of solid acid precursor and particulate solid acid-reactive materials. Then in the presence of water, the solid acid precursor (polylactic acid) hydrolyzes and dissolves, generating acids that then dissolve the solid acid-reactive materials (calcite). It effectively stimulates the horizontal section right after drilling and eliminates acidizing, resulting in significant cost savings, and improves filter-cake removal, thus enhancing the performance of the treated wells.
A series of experiments have been run in the lab to determine the efficiency of this new system. Properties of this drilling fluid are measured. Experiments on solid acid particle size showed that the best size-distribution of solid acid precursor and solid reactive material to make a self-destructing filter cake is fine particles of calcium carbonate used as weighting material with 150 microns polylactic acid as solid acid precursor. By comparison of the results of the experiments at different temperatures, 230 degrees F has been chosen as the best temperature for running experiments. The self-destructing drilling fluid systems need enough time for the solid acid to be hydrolyzed and therefore remove the filter cake. After 20 hours of contact with the water as the only cleaning solution, about 80 percent of the filter cake was removed. Calcite is found to be the dominant compound in the sample of remained filter cake, which was proved by x-ray diffraction tests. Secondary electron microscopy (SEM) results show the morphology of the remained filter cake sample and confirm the crystalline area of calcite.
|
5 |
Geomicrobial Processes and Diversity in Ultra-High Pressure Metamorphic Rocks and Deep Fluids from Chinese Continental Scientific Deep DrillingZhang, Gengxin 01 December 2006 (has links)
No description available.
|
6 |
Otimização de sistemas de fluidos aquosos altamente inibidos. / Optimization of highly inhibited aqueous fluid systems.LEITE, Raquel Santos. 18 April 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-04-18T15:15:54Z
No. of bitstreams: 1
RAQUEL SANTOS LEITE - DISSERTAÇÃO PPG-CEMat 2014..pdf: 1921020 bytes, checksum: 963eb1edee3115174a9a06b4af8c7f59 (MD5) / Made available in DSpace on 2018-04-18T15:15:54Z (GMT). No. of bitstreams: 1
RAQUEL SANTOS LEITE - DISSERTAÇÃO PPG-CEMat 2014..pdf: 1921020 bytes, checksum: 963eb1edee3115174a9a06b4af8c7f59 (MD5)
Previous issue date: 2014-08-27 / Os fluidos inibidos são empregados na perfuração de folhelhos hidratáveis para
evitar que as argilas encontradas sejam hidratadas e causem prisão de
ferramentas. O conhecimento das propriedades de filtração dos fluidos é
importante durante a perfuração de poços, uma vez que o controle dessas
propriedades garante menos problemas de perfuração e melhora a produtividade
dos poços. Assim, este trabalho teve como objetivo estudar e aperfeiçoar as
propriedades de filtração de fluidos aquosos, inibidos com sal de potássio isentos
de cloro (citrato de potássio), visando sua aplicação na perfuração de formações
argilosas e folhelhos hidratáveis e dispersivos. Para tanto, foram estudados
fluidos de perfuração com e sem adição do inibidor citrato de potássio. Foram
determinadas as propriedades reológicas (viscosidades aparente (VA) e plástica
(VP), limite de escoamento (LE) e força gel (FG)), filtração (volume de filtrado
(VF), spurt loss (SL), espessura de reboco (ER) e permeabilidade (k)) e o poder
de inibição (ensaios de dispersibilidade e o teste de inibição de bentonita) dos
fluidos estudados. De acordo com os resultados obtidos conclui-se que os fluidos
estudados apresentaram comportamento pseudoplástico e a adição do citrato de
potássio ao fluido não ocasionou mudança no comportamento pseudoplástico dos
fluidos. Concluiu-se ainda, que o uso conjunto dos aditivos amido, CMC BV e
calcita reduz de forma mais efetiva as propriedades de filtração dos fluidos de
perfuração estudados e que as propriedades de filtração dos fluidos inibidos com
citrato de potássio foram otimizadas, uma vez que os valores de VF obtidos foram
inferiores ao do fluido tido como base. As formulações que apresentaram
eficientes propriedades de filtração e inibição foram preparadas com altas
concentrações de citrato de potássio. As mesmas apresentaram baixos valores de
VF e menores valores de SL. / The inhibited fluids are used in drilling hydratable shales, to prevent found clays to
be hydrated and cause stuck tools. The knowledge of the filtration properties of the
fluids is important during drilling, since the control of these properties ensures less
drilling problems and improves well productivity. This work aimed to study and
improve the filtration properties of aqueous fluids inhibited with potassium salt
chlorine-free (potassium citrate), for their application in drilling hydratable and
dispersive clays and shales. For this purpose, the drilling fluids with and without
addition of the inhibitor potassium citrate were studied. It was determined the
rheological properties (apparent viscosity (AV), plastic viscosity (PV), yield limit
(YL) and gel strength (GS)), filtration (filtrate volume (FV), spurt loss (SL), cake
thickness (CT) and permeability (k)) and the inhibition power (dispersibility test and
the bentonite inhibition test) of the studied fluids. According to the obtained results
it was concluded that the study fluids showed pseudoplastic behavior and addition
of potassium citrate to the fluid did not cause changes in the pseudoplastic
behavior of fluids. It was concluded that the combined use of additives starch,
CMC LV and calcite reduces more effectively the filtration properties of drilling
fluids studied and the filtration properties of the fluids inhibited with potassium
citrate were optimized since the FV values obtained were lower than the
considered base fluid. The formulations which showed efficient filtration and
inhibition properties were prepared with high concentrations of potassium citrate.
They have presented low values of FV and lower values of SL.
|
7 |
Estudo do comportamento reológico de suspensões aquosas de bentonita e CMC: influência da concentração do NaCl. / Study of the rheological behavior of aqueous suspensions of bentonite and CMC: effect of NaCl concentration.Shiroma, Priscila Hiromi 11 May 2012 (has links)
O sucesso da conclusão de um poço por perfuração e o custo do projeto estão relacionados às propriedades dos fluidos de perfuração. O estudo experimental foi realizado a partir da determinação e análise das curvas de tensão de cisalhamento versus taxa de deformação de suspensões aquosas de bentonita e carboximetilcelulose com diferentes concentrações de NaCl. Investigou-se, inicialmente, o comportamento reológico de suspensões de carboximetilcelulose 0,5% (em massa) com concentrações de sal, NaCl de 0 a 4% (em massa), para temperaturas variando de 14 a 26ºC. Os resultados experimentais possibilitam a caracterização reológica destas soluções como fluidos pseudoplásticos e indicam que a adição de NaCl em soluções com CMC alteram significativamente o comportamento reológico desse tipo de solução. Numa segunda etapa, estudou-se o comportamento reológico de suspensões de bentonita e carboximetilcelulose em diferentes concentrações de sal, NaCl. Empregaram-se soluções contendo 4,8 % de bentonita, 0,5 % de carboximetilcelulose e concentrações de 0 a 4% de NaCl. Constata-se o comportamento tixotrópico destas suspensões e a forte dependência com a concentração de sal. O estudo foi complementado com uma análise comparativa dos resultados do comportamento reológico obtidos por reômetro de cilindros coaxiais modelo Brookfield e o viscosímetro FANN 35 A, usualmente empregado na análise de fluidos de perfuração. O equacionamento do escoamento do fluido nos aparelhos permitiu uma interpretação mais detalhada dos valores descritos na norma, obtendo-se uma equivalência dos valores medidos em campo com os obtidos no reômetro Brookfield apesar de as faixas de operação de taxas de deformação serem distintas. / The properties of drilling fluids have a very significant effect on the successful of a well completion and the project costs. The experimental study was conducted based on the determination and analysis of the curves of shear stress and shear rate of aqueous suspensions composed of bentonite and carboxymetil cellulose at different concentrations of NaCl. The rheological behaviour of carboxymetil cellulose suspensions 0.5% w/w at NaCl concentrations in the range of 0 to 4% w/w from 14 to 26°C was studied. The experimental results allow the rheological characterization of these solutions as pseudoplastic fluid. It was observed that the addition of NaCl to CMC solutions changes its rheological behaviour significantly. In addition, the rheological behaviour of 4,8% bentonite suspensions with 0,5% carboxymethyl cellulose at different concentrations of NaCl in the range of 0 to 4% was studied. The characterization of these solutions showed thixotropic behaviour and a strong dependence on the salt concentration. The study was complemented with a comparative analysis of the results obtained by using a coaxial cylinders rheometer model Brookfield and the FANN Model 35 A viscometer, usually employed in drilling fluids analysis. The analytical solutions allowed a more detailed interpretation of the values described in the standard resulting in an equivalence between the measured values obtained in the field and in the Brookfield rheometer despite the differents shear rate ranges.
|
8 |
Din?mica do b?rio em solos contaminados por res?duos oriundos da perfura??o de po?os de petr?leo. / The dyamics of barium in soil contaminated by the waste generated from oil well drilling.Magalh?es, Marcio Osvaldo Lima 19 December 2011 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-09-28T13:47:04Z
No. of bitstreams: 1
2011- Marcio Osvaldo Lima Magalhaes.pdf: 4632406 bytes, checksum: 8ccefc16f724417fcb426aaf9aac9f4a (MD5) / Made available in DSpace on 2016-09-28T13:47:04Z (GMT). No. of bitstreams: 1
2011- Marcio Osvaldo Lima Magalhaes.pdf: 4632406 bytes, checksum: 8ccefc16f724417fcb426aaf9aac9f4a (MD5)
Previous issue date: 2011-12-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Despite the known problems caused by the by-products generated from the exploration of oil,
this activity will be a part of our reality for the next 50 years. The oil drilling and exploration
industry creates a substantial amount of waste that, if not adequately disposed of, could cause
environmental problems. One of the main contaminates found in the waste related to oil
drilling is the element barium. The purpose of this study was to evaluate the contamination of
soil containing barium, its impact on the growth of rice plants (Orysa sativa) and potential
risk of contaminating groundwater. This paper was divided into four chapters. The goal of the
first chapter was to evaluate the spatial variability of barium levels found in former oil well
drilling waste disposal sites. For this study, soil was collected from georeferenced points,
analyzed in terms of its pseudo total levels, and prepared for the geochemical fractionation of
barium, classifying the material in accordance with resolution 420 of CONAMA [Brazilian
National Counsel on the Environment] (2009). In the second chapter, the effect of redox
potential in soil on the mobility and absorption of barium by rice, having barium sulfate P.A.
as the element?s source, was assessed. The effect was evaluated by performing rice culture pot
and column leaching tests. The aim of the third chapter was the characterization and
traceability of heavy metals in waste generated during the recovery of oil well drilling fluids.
The waste was collected during the drilling of well 7-MGP-98D-BA, where the material was
separated by composite sample, based on depth and equipment. In the fourth chapter, the
effects of redox potential in soil interaction and heavy metals coming from the waste
generated from onshore oil well drilling were analyzed. This chapter was similar to chapter
two, with the main difference being the waste generated from well 7-MGP-98D-BA, which
supplied the source of barium. The waste materials selected were those that displayed the
lowest levels of arsenic, cadmium, barium, lead, and sodium. The obtained results showed
that waste generated from oil well drilling contains high levels of barium, and that when
disposed of in soil can significantly contribute to site contamination, having used the guiding
values of CONAMA (2009) as a reference. As such, the barium present in this area was in the
form of low solubility, as evidenced by the geochemical fractionation of the element. It was
also observed that the conditions of low values of redox potential (-200 mV) promoted an
increase of barium in fractions of greater mobility, causing major losses of the element by
leaching, and increased absorption by plants. Among the studied waste materials, the waste
from the dehydrator and the centrifuge 1 presented high levels of sodium as its greatest
limitation, which affected the development of plants. / Apesar da verifica??o de problemas ocasionados pelo uso de produtos gerados a partir da
explora??o do petr?leo, essa atividade ? uma realidade nos pr?ximos 50 anos. A industria de
perfura??o e explora??o de petr?leo ? uma atividade que gera muitos residuos que, caso
dispostos de forma inadequada, podem ocasionar problemas ambientais. Um dos principais
contaminantes relacionados aos res?duos de perfura??o de po?os de petr?leo ? o elemento
b?rio. A proposta desse estudo foi de avaliar a contamina??o dos solos com b?rio e seu
impacto no desenvolvimento de plantas de arroz (Orysa sativa) e o risco de contamina??o do
len?ol fre?tico. Para isso o trabalho foi dividido em quatro cap?tulos. O primeiro cap?tulo teve
como objetivo avaliar a variabilidade espacial dos teores de b?rio em antiga ?rea de
disposi??o de res?duo de perfura??o de po?os de petr?leo. Nesse estudo foram coletados solos
em pontos georreferenciados e analisados quanto aos teores pseudototais e feito o
fracionamento geoqu?mico do b?rio, classificando o material de acordo com a resolu??o 420
do Conama (2009). No segunto cap?tulo foi avaliado o efeito do potencial redox do solo na
mobilidade e absor??o de b?rio por arroz, tendo como fonte do elelmento o sulfato de b?rio
P.A. Esse efeito foi avaliado atrav?s de ensaios em vasos com cultivo de arroz e em colunas
de lixivia??o. O terceiro cap?tulo teve como objetivo a caracteriza??o e rastreabilidade de
metais pesados em res?duos gerados na recupera??o do fluido de perfura??o de po?os de
petr?leo. O res?duo foi coletado durante a perfura??o do po?o 7-MGP-98D-BA, onde os
materiais foram separados em amostras compostas em fun??o da profundidade e do
equipamento. No quarto cap?tulo foi analisado o efeito do potencial redox na intera??o solo e
metais pesados provenientes de res?duos oriundos da perfura??o de po?os de petr?leo
?onshore?. Esse cap?tulo foi semelhante ao cap?tulo 2, diferindo principalmente na fonte de
b?rio que foi o res?duo gerado no po?o 7-MGP-98D-BA. Os res?duos selecionados foram os
que apresentaram como os mais restrit?vos com rela??o aos teores de ars?nio, c?dmio, b?rio,
chumbo e s?dio. Os resultados obtidos evidenciaram que os res?duos oriundos da perfura??o
de po?os de petr?leo possuem altos teores de b?rio, que quando dispostos nos solos podem
contribuir significativamente para a contamina??o das ?reas, tendo como refer?ncia os valores
orientadores do Conama (2009). Entretanto, o b?rio presente nessa ?rea estava sob forma de
baixa solubilidade, evidenciada pelo fracionamento geoqu?mico do elemento. Tamb?m foi
observado que a condi??o de baixos valores de potencial redox (-200 mV) promoveu o
aumento do b?rio nas fra??es de maior mobilidade, ocasionando maiores perdas do elemento
por lixivia??o e maior absor??o pelas plantas. Dentre os res?duos estudados, os res?duos do
secador e da centr?fuga 1 apresentaram como maior limita??o os altos teores de s?dio, o que
afetou o desenvolvimento das plantas.
|
9 |
Influência da variação granulométrica de argilas bentoníticas no comportamento reológico e de filtração de fluidos de perfuração base águaCaetano, André Luiz Araújo 28 February 2014 (has links)
Made available in DSpace on 2015-04-01T12:17:42Z (GMT). No. of bitstreams: 1
arquivototal.pdf: 1676391 bytes, checksum: 8c1712b1a1b20bab712cd61fd62f5650 (MD5)
Previous issue date: 2014-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The physical characteristics as particle size distribution, density, shape, specific surface area and surface roughness affects the rheological behavior of dispersions. The objective of this work is to study the influence of particle size variation of bentonite clay used as viscosifying agents in water based drilling fluids, the rheological and filtration properties. For both six bentonite clays from deposits in Boa Vista, PB, which were prepared for physical and mineralogical characterization were selected. Then, they were crushed and sieved into different sieve ABNT N° 80, 200 and 325 (180, 75 and 45 μm), being determined from the particle size distribution by laser diffraction their dispersions and then treatment performed with a solution of sodium carbonate (Na2CO3 ) determining the rheological and filtration properties of their aqueous dispersions. We also evaluated the influence of two different curing conditions on the transformations performed on the polycationic bentonite with sodium in their rheological properties. Clays had physical and mineralogical characteristics typical of bentonite clays. The variation of the openings of the sieves influenced, in general, only the accumulated mass below 2 μm who showed greater for sieve clays in the opening 45 μm and all size analysis showed monomodal distribution. It was observed that, in general, the decrease in average particle diameter and increase in cumulative weight below 2 μm, VA is decreased. It was not possible to generalize the influence given by the size of the particles in the VP and VF. The curing time longer possible to clays which had accumulated mass lower than 2 μm (clay) higher to obtain dispersions with thixotropic characteristics and higher and lower values of VA and VP. It was not possible to generalize the influence of curing time in VF. The fine particles of bentonite have great tendency to form agglomerates hindering the analysis of the actual particle size and its relation to the rheological properties. / As características físicas das partículas como distribuição granulométrica, densidade, formato, área superficial específica e rugosidade superficial afetam o comportamento reológico de dispersões. O objetivo deste trabalho é estudar a influência da variação granulométrica de argilas bentoníticas utilizadas como agentes viscosificantes em fluidos de perfuração base água, nas propriedades reológicas e de filtração. Para tanto, foram selecionadas seis argilas bentoníticas provenientes de jazidas do município de Boa Vista, PB, que foram preparadas para caracterização física e mineralógica. Em seguida foram moídas e peneiradas em diferentes peneiras ABNT n° 80, 200 e 325 (180, 75 e 45 μm), sendo determinadas as distribuições granulométricas de suas dispersões por difração laser e posteriormente realizado o tratamento com solução de carbonato de sódio (Na2CO3) determinando-se as propriedades reológicas e de filtração de suas dispersões aquosas. Também foi verificada a influência de duas diferentes condições de cura realizadas nas transformações das bentonitas policatiônicas em sódicas em suas propriedades reológicas. As argilas apresentaram características físicas e mineralógicas típicas de argilas bentoníticas. A variação das aberturas das peneiras influenciou, em geral, apenas na massa acumulada abaixo de 2 μm que se apresentou maior para as argilas peneiradas na abertura de 45 μm e todas as análises granulométricas apresentaram distribuição monomodal. Observou-se que, em geral, com a diminuição no diâmetro médio das partículas e aumento na massa acumulada abaixo de 2 μm, ocorre diminuição na VA. Não foi possível generalizar a influência apresentada pelo tamanho de partículas na VP e no VF. O tempo de cura maior possibilita, para as argilas que apresentaram massas acumuladas abaixo de 2 μm (fração argila) mais elevadas, a obtenção de dispersões com características tixotrópicas e com maiores VA e menores valores de VP. Não foi possível generalizar a influência do tempo de cura no VF. As partículas finas de bentonitas apresentam grande tendência em formar aglomerados dificultando a análise do real tamanho de partículas e sua relação com as propriedades reológicas.
|
10 |
Avalia??o e modelagem reol?gica de fluido de perfura??o base ?guaMelo, Klismeryane Costa de 12 September 2008 (has links)
Made available in DSpace on 2014-12-17T15:01:15Z (GMT). No. of bitstreams: 1
klismeryaneCM.pdf: 1762215 bytes, checksum: 0f44499c3657d68cb30deaeefdc7e534 (MD5)
Previous issue date: 2008-09-12 / The determination of the rheology of drilling fluids is of fundamental importance to select the best composition and the best treatment to be applied in these fluids. This work presents a study of the rheological behavior of some addictives used as viscosifiers in water-based drilling fluids. The evaluated addictives were: Carboxymethylcellulose (CMC), Xanthan gum (GX), and Bentonite. The main objective was to rheologically characterize suspensions composed by these addictives, by applying mathematical models for fluid flow behavior, in order to determine the best flow equation to represent the system, as well as the model parameters. The mathematical models applied in this research were: the Bingham Model, the Ostwald de Wale Model, and the Herschel-Bulkley Model. A previous study of hydration time for each used addictive was accomplished seeking to evaluate the effect of polymer and clay hydration on rheological behavior of the fluid. The rheological characterization was made through typical rheology experiments, using a coaxial cylinder viscosimeter, where the flow curves and the thixotropic magnitude of each fluid was obtained. For each used addictive the rheological behavior as a function of temperature was also evaluated as well as fluid stability as a function of the concentration and kind of addictive used. After analyses of results, mixtures of polymer and clay were made seeking to evaluate the rheological modifications provided by the polymer incorporation in the water + bentonite system. The obtained results showed that the Ostwald de Waale model provided the best fit for fluids prepared using CMC and for fluids with Xanthan gum and Bentonite the best fit was given by the Herschel-Bulkley one / A determina??o do comportamento reol?gico dos fluidos de perfura??o ? de fundamental import?ncia para se determinar a melhor composi??o e o melhor tratamento a ser aplicado nesses fluidos. Este trabalho apresenta um estudo sobre o comportamento reol?gico de aditivos utilizados como viscosificantes em fluidos de perfura??o de base ?gua. Os aditivos de estudo deste trabalho foram a Carboximetilcelulose (CMC), a Goma Xantana (GX) e a Bentonita. O objetivo principal foi caracterizar reologicamente suspens?es compostas por esses aditivos, atrav?s da aplica??o de modelos matem?ticos para comportamento de fluxo de fluido, a fim de se determinar a melhor equa??o de fluxo que representa o sistema, bem como os par?metros de modelo. Os modelos matem?ticos aplicados foram o modelo de Bingham, o de Ostwald de Waale e o de Herschel-Bulkley. A fim de se verificar o efeito da hidrata??o dos pol?meros e da argila na reologia do fluido realizou-se um estudo pr?vio do tempo de hidrata??o de cada aditivo. A caracteriza??o reol?gica foi realizada atrav?s de ensaios de reologia, utilizando sistema de cilindros coaxiais, onde se obteve as curvas de fluxo e a magnitude tixotr?pica de cada fluido. A reologia foi avaliada, tamb?m, em fun??o da temperatura para cada um dos aditivos utilizados. Foi realizado, ainda, ensaios de estabilidade em fun??o da concentra??o e do aditivo utilizado. Ap?s an?lises de resultados misturas de pol?mero e argila foram formuladas com o objetivo de avaliar as modifica??es reol?gicas proporcionadas pela incorpora??o do pol?mero no sistema ?gua+ bentonita. Os resultados obtidos mostraram que para fluidos preparados com CMC o modelo que melhor representou este sistema foi o de Ostwald de Waale e para os fluidos preparados com GX e Bentonita o modelo que melhor representou foi o de Herschel-Bulkley
|
Page generated in 0.034 seconds