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1
Sidi, Purnomo. "Investigating the suitability of biomass Eichhornia crassipes as a lost circulation material in water-based drilling muds." Thesis, University of Aberdeen, 2018. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=239377.
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This study investigated the performance of the biomass Eichhornia crassipes plant (ECP) as an additive in water-based drilling-mud. ECP is an invasive plant of fresh water ecosystems, so its use in drilling operations provides a low-cost, sustainable option that has off-site environmental benefits. Mechanical tests were conducted on ECP fibres to determine their stiffness under dried and water-wet conditions. Initial tensile tests on nylon fibre determined potential experimental artefacts with the experimental approach. The dried fibres had a water content of 8.163 wt. % (SE 0.636), whereas the wet fibres were 93.43 wt.% (SE 0.294). Water wet fibres had a lower modulus of elasticity than dried fibres and therefore, dried fibres have less tensile strength than wet fibres (Mean = 45.16 MPa; SE = 5.023; N = 41). Rheological properties of bentonite-based drilling muds amended with ECP at different concentrations were also studied. These muds were prepared by mixing ECP fragments at various concentrations (%w/w) with bentonite-water solutions and aged under ambient conditions. Mud viscosity gradually decreased with increasing shear rate, showing characteristic shear-thinning behaviour. Lost circulation of bentonite-water solutions mixed with ECP fragments were assessed with static filtration experiments. Slots and single perforated discs were designed to mimic fractures surrounding drilled boreholes. From a broad range of testing conditions, it was found that ECP fibres significantly decrease lost circulation by bridging fractures. An optimal concentration of 0.83 % by weight of ground plant stalks mixed with 6.28% bentonite in water improved rheology and filtration properties. A bridging gap model for a single fibre showed that ground stalk was less deflected than dried fibre when bridged an opening fissure. The findings of this research create an alternative to use ECP as lost circulation material in oil and gas drilling operations.
2
Ali, Md Wazed. "A parametric study of cutting transport in vertical and horizontal well using computational fluid dynamics (CFD)." Morgantown, W. Va. : [West Virginia University Libraries], 2002. http://etd.wvu.edu/templates/showETD.cfm?recnum=2281.
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Thesis (M.S.)--West Virginia University, 2002.Title from document title page. Document formatted into pages; contains x, 108 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 42-46).
3
Whyte, John Morrison. "Surfactant-inhibited barium sulphate nanoparticles for use in drilling fluids." Thesis, University of Aberdeen, 2016. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=231876.
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This project studied the production of barium sulphate nanoparticles through inhibition of crystal growth, during precipitation, by different surfactants. Barium sulphate is the pure form of the ore baryte, which due to its high density and softness, is the most commonly used additive used to increase the density of drilling fluids. A non-agglomerating, stable nano-scale dispersion of barium sulphate particles would have significant technical and commercial impact in the drilling fluids industry. This thesis tested the possibility of precipitating barium sulphate and restricting its crystal growth with inhibitors, creating nanoparticles. Six inhibitors were tested; dodecanoic acid, palmitic acid, stearic acid, adamantane carboxylic acid, methylnonanoic acid and a mixture of phosphate esters known commercially as Fazewet. Precipitated, inhibited barium sulphate was characterised using powder XRD, DRIFT FTIR and solid-state NMR (SSNMR). All inhibitors were shown to form single-phase, orthorhombic barium sulphate crystals proving that the inhibitors affect only the surfaces of precipitated crystals and do not enter the crystal lattice. FTIR allowed the relative adsorbed concentration of each inhibitor to be assessed. The results indicate that adsorbed inhibitor increases with increasing inhibitor concentrations but that their attachment is not proportional to the concentration. In most cases concentrations of 0.1mol l-1 of inhibitor were sufficient to saturate the crystal surface. SSNMR also agreed with this although the sample size was too small, due to equipment restrictions, to make definitive conclusions. Through the use of the Debye-Scherrer equation, the crystallite size was calculated and showed that at concentrations of 0.2mol l-1 all inhibitors other than palmitic acid produced nano-scale (< 100nm) crystallites. Further analysis showed that further reductions could be achieved through precipitation in an alkaline pH environment, with the application of mechanical shear and by using adding 50% v/v of ethanol. iv Laser diffraction particle size analysis showed that the dominant factor in reducing particle size distribution was inhibitor concentration. The volume-based PSD used by the laser diffraction system was considered to distort excessively the particle sizes present and so analysis switched to dynamic light scattering. DLS showed that dodecanoic acid, palmitic acid and stearic acid, despite forming nano-scale crystallites, could not produce a nano-scale dispersion of barium sulphate and as such were unsuitable for use in drilling fluids. Stable nano-scale dispersions were found to have been formed when inhibited with adamantane carboxylic acid, methylnonanoic acid and Fazewet. DLS also confirmed that dispersed particle size rather than simply crystallite size could be reduced with an alkaline pH and high mechanical shear. Concentration was still the dominant effect, however with the smallest particles sizes (ZAvg) being observed at concentrations of 0.6mol l-1. The particle sizes for the three modifiers were approaching that of the crystallite size, suggesting that some further reduction is possible, but large reductions are unlikely. All three inhibitors produced sub 100nm ZAvgs, with the smallest produced by methylnonanoic acid of 43nm. Spherical nanoparticles were observed through the use of ESEM and TEM. Due to equipment time restrictions only 0.2mol l-1 treatment levels could be examined, but ESEM showed apparent nanoparticle clusters, later confirmed using pixel count and SFDA methods. TEM analysis showed discrete particles as small as 3nm, indicating that the lower limit for achievable particle size may be lower than PSD measurements would suggest. The results indicate that adamantane carboxylic acid, methylnonanoic acid and Fazewet sufficiently inhibit crystal growth to be potential candidates for the production of barium sulphate nanoparticles. These three inhibitors produce a barium sulphate dispersion that is stable and nano-scale even after drying and redispersion.
4
Niu, Haibo. "Flocculation and settling properties of discharged drilling waste /." Internet access available to MUN users only, 2003. http://collections.mun.ca/u?/theses,159920.
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Mfanga, Dhelda Reginald. "Impact of drilling fluids on geomechanical stability of wellbore." Thesis, University of Aberdeen, 2018. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=239273.
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Xie, Jing. "Models for filtration during drilling, completion and stimulation operations /." Full text (PDF) from UMI/Dissertation Abstracts International, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3008475.
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7
Arthur, Kevin Gordon. "An experimental and theoretical study of the filtration characteristics of water-based drilling muds." Thesis, Heriot-Watt University, 1986. http://hdl.handle.net/10399/1082.
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8
Wang, Hui. "Effect of the drilling fluids IPAR and NEODENE on biotransforming enzymes in rats." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ62438.pdf.
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9
Phelps, Geoffrey David. "A numerical simulator and microwave absorption spectrometer for the study of filtrate invasion dynamics." Thesis, Heriot-Watt University, 1988. http://hdl.handle.net/10399/998.
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10
Won, Suyoun. "Investigation of mud filtrate invasion using computational fluid dynamics." Morgantown, W. Va. : [West Virginia University Libraries], 2008. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=6038.
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Thesis (M.S.)--West Virginia University, 2008.Title from document title page. Document formatted into pages; contains xi, 59 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 52-54).
11
Zhang, Yongsheng. "Aspects of reservoir evaluation and oil recovery." Laramie, Wyo. : [University of Wyoming], 2006. http://proquest.umi.com/pqdweb?did=1367831031&sid=2&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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12
Helgeland, Leif Rune. "Drilling of Deep-set Carbonates Using Pressurized Mud Cap Drilling." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for petroleumsteknologi og anvendt geofysikk, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-25582.
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A majority of the “easy” fields have already been developed, while demand for oil and gas continues to increase rapidly. Reservoirs in deep-set carbonates contains a large amount of the worlds remaining hydrocarbons and could pose as a solution for supplying the future demand. However, extracting these hydrocarbons has proven to be a daunting task. Carbonate formations are often severely fractured and karstified, leading to large or even total losses during drilling. As these fractures and “caves” are also the main target for gas, kicks and blow-outs are a constant threat.In this master thesis a variant of Managed Pressure Drilling (MPD), Pressurized Mud Cap Drilling (PMCD), has been reviewed. PMCD uses a static mud cap in the annulus to provide adequate downhole pressure, while a cheap sacrificial fluid is pumped down the drillstring to remove cuttings and transport it into the formation. A literature study was done in order to compare PMCD against other existing tech- niques, specifically conventional drilling and Constant Bottom Hole Pressure, another MPD variant. Working along side the losses have enabled PMCD to safely drill to Total Depth in these reservoirs, while reducing most of the Non-Productive Time and having an overall cheaper operation. Where other techniques are relying on time consuming and costly Lost Circulation Material, cement or other means of plugging the formation, PMCD works at its optimal.A static model was made to more clearly show the physics behind PMCD and to be able to simulate an operation through a gas bearing total loss ”cave” in a deep- set carbonate environment. Its procedures and advantages became clear, though the model and reservoir environment was rather simplistic. After an evaluation, the results were that PMCD lacks versatility and is not yet fully accepted by the industry, but that it offers the best solution for drilling of deep-set carbonates. The main conclusion is that in these reservoir, PMCD should as a minimum be used as a contingency in exploration wells.
13
ABDU, JOAO PAULO SANSEVERINO. "SAFETY ASPECTS IN OFFSHORE OIL DRILLING WITH THE FLOATING MUD CAP DRILLING TECHNIQUE." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2018. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=36079@1.
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Frente às dificuldades de perfurar poços em reservatórios caracterizados por carbonatos fraturados e depletados, com frequente ocorrência de massivas perdas de fluido para formação e impossibilidade de manter o retorno de fluido para superfície, foi desenvolvida a técnica FMCD- Floating Mud Cap Drilling. A técnica consiste na perfuração com bombeio contínuo de fluido pela coluna de perfuração e também pelo anular do poço, injetando todo fluido e formação cortada pela broca para o reservatório. Na técnica convencional de perfuração, o fluido é bombeado pela coluna e retorna pelo anular, sendo possível monitorar continuamente a ocorrência de kicks - influxos acidentais de hidrocarbonetos no poço No entanto, na técnica FMCD, devido à ausência de retorno de fluido no anular, torna-se necessário adotar métodos não convencionais de monitoramento e prevenção de kicks, sendo o principal método, a injeção continua de fluido pelo anular, a uma vazão determinada, que evite influxos do reservatório e migração de hidrocarbonetos para superfície, denominada vazão de segurança. Inicialmente é apresentada uma contextualização da perfuração de poços offshore com técnica convencional e técnica FMCD, associada a uma ampla revisão bibliográfica sobre a técnica, e também de modelos e experimentos de fluxo óleo-água. Por fim, como objetivo principal da dissertação, é realizado a discussão de premissas, análise da vazão de segurança e métodos de monitoramento de influxos. Contudo, é esperado que a revisão bibliográfica e análises desenvolvidas, auxiliem em futuros projetos de perfuração com a técnica FMCD- Floating Mud Cap. Drilling.With the oil carbonate reservoirs exploration and exploitation around the world and the Brazilian coast, new challenges for well drilling are found which requires new techniques to be developed. The carbonate reservoirs can present fractures with high conductivity along its structure, often accompanied by geological faults. When associate with scenarios where the reservoirs are depleted, due to the ongoing production of these oil fields, may lead to fluid severe losses into the formation during the news well construction. For decades, in case of total loss at offshore wells drilling, the proposed solution has been to pump sealing material into the formation and, persisting the losses, to end it with a cement plug in open hole and make another attempt to drill the interval. When these procedures were not effective, the wells were often abandoned. On one side, it should be emphasized, that pumping sealant material and cement into the producing reservoir is undesirable, due to the possibility of damaging the intervals of greater permeability and production potential which may bring reduction in productivity (or injectivity) of the well. On the other side, continuing the drilling with fluid total loss may be intolerable from the operational safety point of view, as it is not possible to use conventional kick detection methods, that are mainly based on drilling fluid mass control. Facing these difficulties of drilling wells in reservoirs characterized by fractured and depleted carbonates, the FMCD (Floating Mud Cap Drilling) technique was developed. The technique consists of drilling with continuous pumping of fluid both through the drilling column and the well annulus, injecting all fluid and formation cuts into the reservoir.
14
Tripuraneni, Gopi Chand. "Performance Analysis of Enhanced Activated Sludge as Drilling Mud Additive." Thesis, University of Louisiana at Lafayette, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10268960.
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The use of drilling fluids alone is not sufficient to reduce friction substantially, so a suitable lubricant has to be added to the drilling fluid so as to reduce the friction to an acceptable range. The lubricant reduces friction of fluid by producing a thin film of liquid that separates the solid surfaces in contact.
The primary objective of this research is to evaluate the performance of enhanced activated sludge (EAS) as a lubricant in drilling fluids. Enhanced activated sludge is composed of mixed consortium of microorganisms grown under conditions that promote lipid accumulation. Experiments were conducted to evaluate (EAS) with different lipid contents. Performance of EAS as drilling fluid additive was compared with commercial lubricants in terms of lubricity and flow properties. Lubricants are evaluated using water-based drilling mud at lubricant concentrations of 1.78, 3.11, 4.43, and 6.17 pounds per barrel (ppb). Experiments were carried out in a standard lubricity meter. The Lubricity meter tests the ability of the lubricant in the drilling mud to reduce friction. Other parameters measured re plastic viscosity, gel strength, fluid loss, mud cake thickness, sand content, methylene blue test (MBT), alkalinity, and chlorides.
All the lubricants studied (including EAS) lowered the coefficient of friction and significant torque reduction. EAS reduced the torque and fluid loss better than raw sludge. However, the top performers in terms of reducing the torque were the commercial lubricants. Bio Add was the best performer in the presence of both barite and bentonite. HDL+ resulted in the least coefficient of friction when the mud was prepared with only bentonite. A cost analysis was prepared to show the economics involved in using sludge (raw and EAS) as additive in drilling fluids. These findings show the potential of activated sludge for improving the properties of water-based drilling mud.
15
Sonmez, Ahmet. "Performance Analysis Of Drilling Fluid Liquid Lubricants." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613581/index.pdf.
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Excessive torque is one of the most important problems in oil/gas drilling industry. Friction between wellbore/casing and drill string causes excessive torque. This study discusses performance analysis of drilling fluid lubricants, which are used as friction reducers in well-bore. Three different types of commercial chemical lubricants, which are fatty acid and glycerid based, triglycerid and vegetable oil based and polypropylene glycol based, diesel oil, and crude oil, which consists of different API gravity, paraffin and asphaltene value samples, were selected for the analysis.
In the analysis, different lubricant compositions with the mixture of commercial chemical lubricants, crude oil and diesel oil, which were added to water based lignosulfonate mud, are tested on metal-metal contact surface by Ofite Lubricity Tester to determine the best lubricity/cost ratio of lubricant compositions.
Moreover, effects of the lubricants on mud rheology and API fluid loss of mud, foam forming potential and cheesing/greasing of the lubricants and the influence of mud properties on lubricants (calcium, salt, pH and mud density) are examined.
16
Alizadeh, Vahid. "Safety considerations for the choice of drilling mud in offshore operations." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20322/.
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Oil could be considered as one of the most noteworthy resources in the modern era. It does not only prescribe politics and relations among countries but also provide the raw material that moves a great number of other industries and generally the rest of the world. Oil is extracted from the earth by drilling wells, to reach the oil reservoirs. Drilling is the first and foremost aspect of a successful oil and gas producing procedure. This activity needs the use of a drilling fluid known as “mud”, which consists of complex mixtures of hydrocarbons. Specific detail and careful attention must be given to the safety and environmental parameters of this essential component for the drilling operation. In this thesis, a review and classification of main properties, exact components and safety factors of some commercial drilling muds are analyzed, aiming at choosing the appropriate drilling fluids according to safety, cost efficiency and environmental aspects.
17
Toka, Bulent. "Use Of Borates As An Activating Agent For Drilling Mud Bentonites." Phd thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12609410/index.pdf.
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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 asbacterial 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 Ç
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.
18
Elwood, David E. Y. "Hydraulic fracture experiments in a frictional material and approximations for maximum allowable mud pressure." Thesis, Kingston, Ont. : [s.n.], 2008. http://hdl.handle.net/1974/1343.
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Ezekiel, Ekerette Elijah. "EXPERIMENTAL STUDY OF DRILLING MUD RHEOLOGY AND ITS EFFECT ON CUTTINGS TRANSPORT." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for petroleumsteknologi og anvendt geofysikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-19792.
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20
Mok, Soon H. "An investigation of energy-based planned maintenance of offshore drilling mud pumps." Thesis, Robert Gordon University, 1994. http://hdl.handle.net/10059/2136.
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Mud pumps used on offshore installations for drilling operations have been known to experience unpredictable breakdowns, including during critical stages of drilling. The fluid end has been identified as requiring more maintenance work due to component failure, compared to the power end. The most common maintenance strategies in use include breakdown maintenance, time-based maintenance and condition monitoring. Time-based maintenance, based on running hours, is the most commonly preferred method by most, if not all, mud pump operators. However, the nature of drilling operations require pump performance with variable loads (pressures), variable speed characteristics and time-based maintenance would not be able to account for the different operating conditions within any identical time frames. To address this shortcoming, this research looked at the postulation that material wear loss is related to the energy expended and developed a dedicated reciprocating wear test system to identify and investigate the effect of operating variables on the wear loss of piston rubbers, which was considered to be the most problematic of the fluid end components.
21
Gulmammadov, Rashad. "Seismic geomechanics of mud volcanoes." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/seismic-geomechanics-of-mud-volcanoes(e579a3af-0881-4f52-b14a-dd360304f337).html.
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Mud volcanoes constitute an important component of petroliferous basins and their understanding is essential for successful exploration and development of hydrocarbon fields. They occur in both extensional and compressive tectonic settings, along with passive and active continental margins. Although extensive research exists on the geochemistry, geomorphology and stratigraphic evolution of these localized fluid flow structures, little is known about their geomechanical characteristics. This research investigates the geomechanics of mud volcanoes from the South Caspian Basin and West Nile Delta. This is achieved by establishing a workflow for geomechanical assessment of mud volcanoes using a P-wave velocity dataset from across the mud volcano within the offshore South Caspian Basin. This objective is developed further with the availability of seismic and wellbore data from around the Giza mud volcano, offshore West Nile Delta. Preliminary results of this study from the South Caspian Basin enable confidence in estimating the realistic magnitudes of elastic rock properties, stresses and fluid pressures from empirical and analytical correlations. Moreover, analysis of the variations in fluid pressures allow the fluid flow models around the mud volcano to be constrained and their gradients provide preliminary estimates of the drilling window. Structural and stratigraphic analysis around the Giza mud volcano offers insight into the formation of the mud volcano during the Quaternary and how the fault networks on the hanging wall of the arcuate tectonic fault have acted as conduits for primarily the pre-Pliocene fluids exploiting the areas of weakness along the hanging wall of the fault by entraining the Pliocene sediments. Fluid pressure evaluation reveals small overpressures caused by disequilibrium compaction. Further analysis offers insight into the critical fluid pressures that control fault movement, the stresses responsible for rock deformation around the wellbore and the width of the drilling window constrained by the fracturing of the strata. Analysis presented here provides details on the geomechanical significance of mud volcano environments, with implications for engineering practices. Overall, findings contribute to a systematic understanding of mud volcano settings not only from a field exploration and development point of view, but also at a wider scale for basin analysis and relatively small scale for play analysis.
22
Tercan, Erdem. "Managed Pressure Drilling Techniques, Equipment &." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12611824/index.pdf.
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In the most of the drilling operations it is obvious that a considerable amount of money is spent for drilling related problemsincluding stuck pipe, lost circulation, and excessive mud cost. In order to decrease the percentage of non-productive time (NPT) caused by these kind of problems, the aim is to control annular frictional pressure losses especially in the fields where pore pressure and fracture pressure gradient is too close which is called narrow drilling window. If we can solve these problems, the budget spent for drilling the wells will fall, therefore enabling the industry to be able to drill wells that were previously uneconomical. Managed Pressure Drilling (MPD) is a new technology that allows us to overcome these kinds of drilling problems by controlling the annular frictional pressure losses. As the industry remains relatively unaware of the full spectrum of benefits, this thesis involves the techniques used in Managed Pressure Drilling with an emphasis upon revealing several of its lesser known and therefore less appreciated applications.
23
Tekin, Sema. "Estimation Of The Formation Temperature From The Inlet And Outlet Mud Temperatures While Drilling Geothermal Formations." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12611873/index.pdf.
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Formation temperature is an important parameter in geothermal drilling since it affects all the components of the system such as drilling fluid, drilling operations and equipment through mud temperatures. The main objective of this study is to estimate the formation temperatures of five geothermal wells in Germencik-Ömerbeyli geothermal field by using inlet and outlet mud temperatures obtained during drilling. For this purpose, GTEMP, a wellbore thermal simulation model is used to simulate the process of drilling and to estimate the formation and bit temperatures of five wells. With the formation and bit temperature estimations of GTEMP and inlet and outlet mud temperature data from field
temperatures vs. depth graphs are plotted for five wells for two cases. In Case 1, cooling tower effect on mud temperatures is neglected whereas in Case 2 it is taken into account. For the estimation of formation temperature of the final depth, Case 2 showed better results with % 1,5-24,5 deviation compared to the % 3,6-25,2 deviation obtained in Case 1.
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Strachan, Maia Fiona. "Studies on the impact of a water-based drilling mud weighting agent (Barite) on some Benthic invertebrates." Thesis, Heriot-Watt University, 2010. http://hdl.handle.net/10399/2334.
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A comparative study was carried out to observe effects of standard grade and fine grade barite on the filtration rates of four suspension feeding bivalves, Modiolus modiolus, Dosinia exoleta, Venerupis senegalensis and Chlamys varia. Standard grade barite, the most commonly used weighting agent in water-based drilling mud, was responsible for altering the filtration rates of the four bivalve species and damaging the gill structure. The four bivalves were exposed to 0.5mm, 1.0mm and 2.0mm daily depth equivalents of standard grade barite, which permanently remained in suspension. All three barite levels altered the filtration rates leading to 100% mortality. The horse mussel, Modiolus modiolus was the most tolerant to standard barite with the scallop, Chlamys varia the least tolerant. Fine grade barite, at a 2mm daily depth equivalent, also altered the filtration rates of the four bivalve species, but only affected mortality of Venerupis senegalensis, with 60% survival at 28 days. In-vivo studies showed damage to the gills, ranging from displaced inter-lamellar junctions to the deletion of large parts of demibranch. Post-mortem microscopy studies showed damage to individual filaments with a marked reduction in the active surface area of the gill. Field studies have shown that the presence of standard grade barite is not acutely toxic to seabed fauna but does alter benthic community structure when it is persistent.
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Kahvecioglu, Alper. "Designing Lost Circulation Pills For Polymer Based Drill-in Fluids." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12610226/index.pdf.
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Specially designed non-damaging lost circulation pills (LCP) are being effectively applied for drilling depleted zones worldwide. Optimizing the LCP compositions stop the lost circulation effectively and protect the production zone from liquid and solids invasion significantly. Shape, particle size distribution and concentration of the lost circulation materials (LCM) are key parameters determining the effectiveness of LCP. In this study, the Permeability Plugging Apparatus (PPA) is utilized to evaluate effectiveness of various LCM&rsquos in curing the lost circulation. Sized calcium carbonates are used as LCM in different concentrations and in different particle size distribution. Lost circulation zones are simulated using the ceramic disks and slotted disks. Ceramic disks with nominal pore sizes 20, 35, 60, 90, and 150 microns are characterized in terms of pore size distribution using the computerized image analysis technique. Filter cake quality, spurt loss and filtrate volume are basic parameters to be evaluated in this study. Tests are performed at 75 F and 300 psi of differential.
26
Volec, Martin. "Malá vrtná souprava pro vrtání studní." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-232188.
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The aim of this thesis is the structural design small drilling rigs for drilling wells. Drilling rig will be used for drilling wells up to 200 mm diameter rotary drilling technology with irrigation water. The first part is a literature search of small drilling rigs. In the second part, then custom design a small drilling rig.
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Mullins, Miles Patrick. "Automated Device to Measure Slurry Properties in Drilled Shafts." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6333.
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Slurry is the fluid within a drilled excavation that is introduced when an excavation is deeper than the water table or where additional stability is needed for loose sandy dry soils. Although construction practices vary greatly throughout the country and the world, slurry levels should be maintained above the existing ground water level by a suitable margin. The most widely used slurry type is mineral slurry formed by mixing dry clay powder with water; either bentonite or attapulgite powder may be used (attapulgite being used in saline water conditions). Regardless of whether the slurry material is mineral, polymer or natural, the construction practice must address the slurry properties to ensure the stability of the excavation is never compromised.
Proper performance of slurries used to stabilize drilled shaft excavations is maintained by assuring the density, viscosity, pH, and sand content stay within specified limits. These limits have been set either by past experience, research findings and/or by manufacturer recommended values. However, field slurry testing is time consuming as all measurements are manually performed. With the overwhelming advances in digital down-hole devices, it is not unreasonable to assume that slurry property tests are equally applicable to this trend. This formed the basis of this project.
The most commonly used test to indicate slurry viscosity is the Marsh Funnel Test which is essentially a timed flow for a fixed volume of slurry to exit a falling head funnel. Using a library of unique pressure versus flow rate responses for a wide range of slurry viscosities, an automated downhole device was designed and tested that incorporated this information to estimate viscosity in the excavation without the need to remove slurry in order to test. Direct measurement of slurry density was also incorporated into the device and the sand content was computed from density and the viscosity where the suspended solids that make up the density stems from both the slurry products and the soil cuttings.
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Бейзик, О. С. "Підвищення якості розкриття продуктивних горизонтів на родовищах Прикарпаття." Thesis, Івано-Франківський національний технічний університет нафти і газу, 2011. http://elar.nung.edu.ua/handle/123456789/4417.
Full textAbstract:
Дисертацію присвячено проблемі підвищення якості розкриті продуктивних горизонтів на родовищах Прикарпаття завдяки розробці та впровадженню рецептури безглинистого крохмально-калієвого бурового розчину, нових хімічних реагентів та застосування інгібіторів деструкції та ініціаторів ферментації крохмалю. На підставі аналізу гірничо-геологічних умов, типів бурових розчинів та огляду літературних джерел зроблено висновок про необхідність розробки рецептури бурового розчину на основі вітчизняних хімічних реагентів з таким характеристиками, які б забезпечували збереження первинних фільтраційних: властивостей колекторів. Проведено теоретичні та лабораторні дослідження, на підставі яки; розроблено рецептуру безглинистого крохмально-калієвого розчину (БККР) Досліджено технологічні властивості, вивчено вплив температури та інших чинників на властивості БККР. Проведено серію лабораторних експериментів : дослідження впливу інгібіторів деструкції на ферментативну стійкості крохмальних реагентів під час буріння свердловини та ініціаторів ферментації на руйнування структури молекули крохмалю під час освоєння свердловин Запропоновано спосіб розкриття тріщинуватих продуктивних горизонтів : низькими пластовими тисками. Виконано теоретичні та експериментальні дослідження з покращенні властивостей крохмальних реагентів, у результаті яких отримано карбоксильний крохмальний реагент (ККР), який розчинний у воді, термостійкий та стійкий де ферментативної деструкції. Розроблено рекомендації на приготування безглинистого крохмально-калієвого розчину, які передані для промислового впровадження. Проведене промислові випробування ККР під час буріння свердловин на родовищах Стрийського ВБР, які підтвердили його ефективність під час регулюванні параметрів бурових розчинів.Диссертация посвящена проблеме повышения качества вскрытия продуктивных горизонтов на месторождениях Прикарпатья благодаря разработке и внедрению рецептуры безглинистого крахмально-калиевого бурового раствора, новых химических реагентов, а также применения ингибиторов деструкции и инициаторов ферментаци крахмала. Проведен анализ горно-геологических условий вскрытия продуктивных горизонтов, свидетельствующий о превалирующем наличии в разрезе месторождений низкопроницаемых коллекторов с низкой пористостью и пластовыми давлениями, характеризующимися коэффициентами аномальности пластовых давлений примерно равными 1,02-1,09. Коллекторы нефти и газа на месторождениях Прикарпатья представлены песчаниками и алевролитами, цементирующим материалом которых является глинистий минерал монтмориллонитового типа с обменной емкостью 35-50 мг.екв/100 г и глинистостью 20-24%. Анализируя типы буровых растворов, чаще всего применяющихся при вскрытии продуктивных горизонтов, сделан вывод, что их основными недостатками являются наличие глинистой составляющей, относительно высокий показатель фильтрации (около 8-10 см3/30 мин.), наличие реагентов-полимеров, которые, адсорбируясь на поверхности пор и трещин, уменьшают их эффективный размер. Применение безглинистых биополимерных растворов улучшает качество вскрытия, но эти растворы владеют высоким показателем pH, что способствует набуханию материнских глин. Поэтому, учитывая проделанный анализ и обзор литературных источников, было определено направление научных исследований и выбраны составляющие раствора, а также сделан вывод о разработке рецептуры бурового раствора на основании отечественных химических реагентов с такими характеристиками, которые обеспечат сохранение первичных фильтрационных свойств коллекторов. Проведены теоретические и лабораторные исследования, на основании которых разработана рецептура безглинистого крахмально-калиевого раствора (БККР), главной особенностью которого является формирование структуры раствора за счет комбинации концентрированного водного раствора ЭКР и технического хлористого калия. Исследовано технологические свойства, изучено влияние температуры и других факторов на свойства БККР. Проведен комплекс исследований, связанный с изучением влияния разработанного раствора на коллекторские свойства продуктивных горизонтов, в результате которого устанвовлено, что коэффициент восстановления проницаемости колеблется в пределах 0,95-0,98. Предложен способ вскрытия трещиноватых продуктивных горизонтов с низкими пластовыми давлениями. Проведены теоретические и экспериментальные исследования по улучшению свойств крахмальных реагентов, в результате которых получен карбоксильный крахмальный реагент (ККР), растворимый в воде, устойчивый к высоким температурам и ферментативной деструкции. Проведена серия лабораторных экспериментов по исследованию влияния ингибиторов деструкции на ферментативную устойчивость крахмальных реагентов при бурении скважин и инициаторов ферментации на разрушение структуры молекулы крахмала при освоении скважин. Разработаны рекомендации на приготовление безглинистого крахмальнокалиевого раствора, которые были переданы для промышленного внедрения. Проведены промышленные испытания ККР при бурении скважин на месторождениях Стрыйського ОБР, подтвердившие его эффективность при регулировании параметров буровых растворов.
The thesis is devoted to the enhancement of the quality of productive reservoir opening on the fields of the Precarpathia due to the development and introduction of the formula of clayless amylaceous-potassium drilling mud, new chemical reagents and application of the destruction inhibitor and initiator of starch fermentation. Based on the analysis of mining and geological conditions, types of drilling mud and survey of literary sources a conclusion has been made of the necessity to develop drilling mud formulas on the basis of native chemical reagents which preserve primary reservoir filtration characteristics. On the basis of conducted theoretical and laboratory research the formula of clayless amylaceous-potassium drilling mud (CAPDM) has been developed. Technological characteristics were investigated and influence of temperature and other factors on CAPDM properties were studied. A serious of laboratory experiments have been conducted to study the influence of destruction inhibitors on the fermentation resistance of amylaceous reagents during the process of well drilling and influence of fermentation initiators on the destruction of starch molecule structure during the process of well development. A method is offered here how to open fractured productive reservoirs with low formation pressures. Theoretical and experimental investigations directed to the improvement of amylaceous reagent properties were done and as a result of them carboxylic amylaceous reagent has been received. It is dissolved in water, thermostable and resistant to the fermentation destruction. The recommendations devoted to the preparation of calyless amylaceous-potassium drilling mud were developed and transferred to industry for the implementation. Industrial testing of carboxylic amylaceous reagent conducted during drilling of wells on the fields of Stryy Drilling Department has proved its efficiency in the regulation of drilling mud parameters.
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Bayagbon, Anthony Mamurhomu. "Impact assessment of the environmental protection policies in the upstream oil industry in Nigeria / A.M. Bayagbon." Thesis, North-West University, 2011. http://hdl.handle.net/10394/6276.
Full textAbstract:
The need for energy and the associated economic benefits from the oil and gas deposits found mainly in
the Niger Delta region of Nigeria necessitated the exploration and exploitation activities being carried
out by the oil and gas Companies. However, these exploration and exploitation activities due to their
unpredictable nature have a huge potential for environmental pollution as been experienced in the form
of oil spills, gas flaring, irresponsible disposal of waste and several other activities that have resulted in
the environmental degradation of the Niger Delta region.
In the light of these, the Federal Government of Nigeria having experienced the consequences of
pollution of the environment during the Koko Toxic Waste Dump incident in the then Bendel State in
1987 established a regulatory body tasked with the responsibility of harmonizing the economic interest
from the oil and gas exploration and exploitation activities with the sustainability of the natural
environment by developing well structured and articulated policies aimed at guiding the operations of
the oil and gas operators, track their compliance and administer appropriate punitive measures for non
compliance.
However, this research work which is aimed at evaluating the impact of the environmental protection
policies in upstream oil and gas activities in the Niger Delta region, involved the use of questionnaires
and interviews. These questionnaires were completed by the management and staff of three major oil
and gas companies operating within the area, the Department of Petroleum Resources and members of
the Host communities. The interview was carried out to provide relevant feedback on their assessment
of the impact made by the environmental protection policies on the upstream oil and gas activities in
their operational areas/host communities.
The study however concluded that “Although there is a regulatory body tasked with the responsibility to
develop, implement and track compliance of the environmental protection policies in the upstream oil
industry, the body is ineffective and as such the impact of the environmental protection policies is
inadequate.
Appropriate informed recommendations on the improvement strategies to the identified gaps that
resulted in the unfavorable conditions were also provided.Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2011
30
Fedele, Alessandro <1984>. "Continuous geochemical monitoring by mass-spectometer in the Campi Flegrei geothermal area. An application at Pisciarelli-Solfatara (diffuse and fumarolic gases) and at the mud gases during drilling of the CFDDP pilot hole." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5180/1/TESI_DI_DOTTORATO.pdf.
Full textAbstract:
During this work has been developed an innovative methodology for continuous and in situ gas monitoring (24/24 h) of fumarolic and soil diffusive emissions applied to the geothermal and volcanic area of Pisciarelli near Agnano inside the Campi Flegrei caldera (CFc). In literature there are only scattered and in discrete data of the geochemical gas composition of fumarole at Campi Flegrei; it is only since the early ’80 that exist a systematic record of fumaroles with discrete sampling at Solfatara (Bocca Grande and Bocca Nuova fumaroles) and since 1999, even at the degassing areas of Pisciarelli. This type of sampling has resulted in a time series of geochemical analysis with discontinuous periods of time set (in average 2-3 measurements per month) completely inadequate for the purposes of Civil Defence in such high volcanic risk and densely populated areas. For this purpose, and to remedy this lack of data, during this study was introduced a new methodology of continuous and in situ sampling able to continuously detect data related and from its soil diffusive degassing. Due to its high sampling density (about one measurement per minute therefore producing 1440 data daily) and numerous species detected (CO2, Ar, 36Ar, CH4, He, H2S, N2, O2) allowing a good statistic record and the reconstruction of the gas composition evolution of the investigated area. This methodology is based on continuous sampling of fumaroles gases and soil degassing using an extraction line, which after undergoing a series of condensation processes of the water vapour content - better described hereinafter - is analyzed through using a quadrupole mass spectrometer
31
Fedele, Alessandro <1984>. "Continuous geochemical monitoring by mass-spectometer in the Campi Flegrei geothermal area. An application at Pisciarelli-Solfatara (diffuse and fumarolic gases) and at the mud gases during drilling of the CFDDP pilot hole." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5180/.
Full textAbstract:
During this work has been developed an innovative methodology for continuous and in situ gas monitoring (24/24 h) of fumarolic and soil diffusive emissions applied to the geothermal and volcanic area of Pisciarelli near Agnano inside the Campi Flegrei caldera (CFc). In literature there are only scattered and in discrete data of the geochemical gas composition of fumarole at Campi Flegrei; it is only since the early ’80 that exist a systematic record of fumaroles with discrete sampling at Solfatara (Bocca Grande and Bocca Nuova fumaroles) and since 1999, even at the degassing areas of Pisciarelli. This type of sampling has resulted in a time series of geochemical analysis with discontinuous periods of time set (in average 2-3 measurements per month) completely inadequate for the purposes of Civil Defence in such high volcanic risk and densely populated areas. For this purpose, and to remedy this lack of data, during this study was introduced a new methodology of continuous and in situ sampling able to continuously detect data related and from its soil diffusive degassing. Due to its high sampling density (about one measurement per minute therefore producing 1440 data daily) and numerous species detected (CO2, Ar, 36Ar, CH4, He, H2S, N2, O2) allowing a good statistic record and the reconstruction of the gas composition evolution of the investigated area. This methodology is based on continuous sampling of fumaroles gases and soil degassing using an extraction line, which after undergoing a series of condensation processes of the water vapour content - better described hereinafter - is analyzed through using a quadrupole mass spectrometer
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Sharma, Shekar. "Evaluating Leachability of Residual Solids Generated from Unconventional Shale Gas Production Operations in Marcellus Shale." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/50514.
Full textAbstract:
Hydraulic fracturing operations utilized for shale gas production result in the generation of a large volume of flowback and produced water that contain suspended material, salts, hydrocarbons, metals, chemical additives, and naturally-occurring radioactive material. The water is impounded at drilling sites or treated off-site, resulting in significant generation of residual solids. These are either buried on site or are disposed in lined landfills. The objective of this study was to determine the levels of heavy metals and other elements of concern that will leach from these residual solids when placed in typical disposal environments.
For this purpose, laboratory leaching experiments were employed wherein representative samples were brought into contact with a liquid to determine the constituents that would be leached by the liquid and potentially released into the environment. The samples used included sludge resulting from the physicochemical treatment of process water (TS), sludge solidified with cement kiln dust (SS), raw solids obtained by gravity separation of process water (RS), and drilling mud (DM). The samples were subjected to both single extraction (i.e. Shake Extraction Test, SET) and multiple extraction (i.e. Immersion Test, IT) leaching tests. For the shake extraction test, samples were mixed with a specific amount of leaching solution without renewal over a short time period. In the immersion test, samples were immersed in a specific amount of leaching solution that was periodically renewed over a longer period of time. For both these tests, analyses were performed on the filtered eluate. The tests were performed as per standards with modifications. Distilled de-ionized water, synthetic acid rain (pH ~ 4.2), weak acetic acid (pH ~ 2.88), and synthetic landfill leachate were used as leaching solutions to mimic specific disposal environments.
Alkali metals (Li, K, Na), alkaline earth metals (Ba, Ca, Mg, Sr) and a halide (Br), which are typically associated with Marcellus shale and produced waters, leached at high concentrations from most of the residual solids sample. The SS sample, due to its stabilization with CKD, had a lower extraction efficiency as compared to the unconsolidated TS and RS samples. In EF 2.9 and EF SLL, the leaching took place under acidic conditions, while for EF DDI and EF 4.2, the leaching occurred in alkaline conditions. EF 2.9 and EF SLL were determined to be the most aggressive leaching solutions, causing the maximum solubility of most inorganic elements. Thus, high amounts of most EOCs may leach from these residual solids in MSW landfills disposed under co-disposal conditions. Agitation, pH and composition of the leaching solution were determined to be important variables in evaluating the leaching potential of a sample.
The results of this study should help with the design of further research experiments being undertaken to develop environmentally responsible management/disposal strategies for these residual solids and also prove useful for regulatory authorities in their efforts to develop specific guidelines for the disposal of residuals from shale gas production operations.Master of Science
33
Лубан, С. В. "Підвищення ефективності систем біополімерних безглинистих бурових розчинів." Thesis, Івано-Франківський національний технічний університет нафти і газу, 2017. http://elar.nung.edu.ua/handle/123456789/4885.
Full textAbstract:
Дисертація присвячена підвищенню термічної стійкості систем біополімерних безглинистих бурових розчинів та розробці технології регулювання їх властивостей в умовах високих температур. На підставі теоретичних та експериментальних досліджень встановлено, що зростання межі термічної стійкості, забезпечення високих реологічних характеристик і низьких показників фільтрації біополімерних систем в умовах високих пластових температур можливе внаслідок синергетичної взаємодії солей і білкових речовин. Розроблено і впроваджено у галузі рецептуру мінералізованого біополімерного безглинистого бурового розчину Біокар-МТ, обов’язковим компонентом якого є органо-мінеральний реагент Алеврон, що виконує функції термостійкого регулятора фільтрації та реологічних показників на вибої свердловини. В дисертаційній роботі запропоновано критерій термічної стійкості біополімерних безглинистих систем, досліджено інгібуючі, реологічні, структурно-механічні і фільтраційні властивості бурового розчину Біокар-МТ при температурах до 150 °С.Диссертация посвящена повышению термической устойчивости систем биополимерных безглинистых буровых растворов и разработке технологии регулирования их свойств в условиях высоких температур. Предложен критерий термической устойчивости биополимерных безглинистых систем, соответствующий температуре плавления упорядоченной полимерной структуры жидкости и определяемый как точка перегиба кривой зависимости напряжения сдвига (или вязкости) от температуры. Показана зависимость термической устойчивости от минерализации и солевого состава бурового раствора. Исследованы ингибирующие свойства отдельных солей (хлориды калия, натрия и кальция, нитрат кальция) и их композиций. Установлено синергетическое усиление ингибирующего воздействия биополимерных систем на глинистые породы при совместном применении хлоридов калия и натрия. Ингибирование глинистых пород поливалентными солями при концентрациях свыше 25 - 30 % превышает эффект от применения хлорида калия. Показано, что минерализованные биополимерные системы характеризуются повышенной ферментативной устойчивостью. В системе Биокар при концентрациях солей от 15 % и выше специальные реагенты-бактерициды не используются. Установлено, что снижение показателя фильтрации безглинистых буровых растворов возникает вследствие уменьшения проницаемости корки, сформированной преимущественно грубодисперсными частицами слабо гидратированных инертных наполнителей. Эффективными регуляторами показателя фильтрации таких систем в забойных условиях являются полимерные вещества, способные кольматировать и уплотнять пористую среду корки, а также замедлять температурное разжижение фильтрата и повышать ее гидравлическое сопротивление. Такими свойствами обладают различные типы растительных и животных белков с ограниченной растворимостью. Синергетическое взаимодействие солей и белковых веществ позволяет обеспечить высокие реологические свойства и низкие показатели фильтрации биополимерных систем в условиях высоких температур при одновременном увеличении предела их термической устойчивости. Разработана и внедрена в отрасли рецептура минерализованного биополимерного бурового раствора Биокар-МТ, включающая белоксодержащий реагент Алеврон с функциями термостойкого регулятора фильтрации и реологических свойств в забойных условиях. На основе исследований реологических, структурно-механических и фильтрационных свойств бурового раствора Биокар-МТ получены регрессионные модели, которые позволяют прогнозировать их изменения в зависимости от концентраций реагентов и температур (до 150 °С), а также обосновать выбор оптимальных рецептур для конкретных условий бурения. Теоретические положения диссертационной работы подтверждены успешными промышленными испытаниями разработанной рецептуры биополимерной безглинистой системы Биокар-МТ в сложных горно-геологических условиях Украины.
The thesis is devoted to the topic of the increase of thermal stability of biopolymer clayless drilling mud systems and the development of technology elaborated in order to control their properties at high temperatures. On the basis of theoretical and experimental studies it was established that the increase of thermal stability limit, securing high rheological characteristics and low filtration loss of biopolymer systems at high formation temperatures is possible due to synergistic interaction of salts and protein substances. The recipe of mineralized biopolymer clayless drilling mud Biocar-MT was developed and utilized in practice. Its mandatory component is organic-mineral Alevron agent that serves both as the heat-resistant regulator of filtration and rheological parameters at bottomhole. Given thesis proposes the criterion of thermal stability for clayless biopolymer systems, inhibiting, rheological, structural-mechanical and filtration properties of drilling mud Biokar-MT at temperatures up to 150°C were investigated.
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Malik, Mayank 1979. "Numerical simulation and interpretation of formation-tester measurements acquired in the presence of mud-filtrate invasion." Thesis, 2008. http://hdl.handle.net/2152/3934.
Full textAbstract:
Wireline formation testers (WFT) are widely used to measure fluid pressure, to perform downhole fluid analysis in real-time, and for estimating permeability through pressure transient testing. Formation testers can measure a range of fluid properties such as color, viscosity, density, composition, pH, optical refractive index, pressure, salinity, fractional flow, and gas-oil ratio (GOR). However, WFT measurements are influenced by the process of mud-filtrate invasion because overbalanced drilling promotes radial displacement of in-situ fluids by mud filtrate. Oil-base mud (OBM) is first-contact miscible with native oil and can lead to contaminated fluid samples, erroneous estimates of petrophysical properties, and changes of composition, viscosity, compressibility, GOR, and fluid density. The objective of this dissertation is three-fold: (1) to quantify the effect of OBMfiltrate invasion on WFT measurements, (2) to estimate in-situ petrophysical properties concomitantly from transient measurements of pressure, flow rate and GOR acquired with formation testers, and (3) to quantify petrophysical, geometrical, and fluid properties that can minimize the time of withdrawal of uncontaminated fluid samples. In order to quantify the effect OBM-filtrate invasion on WFT measurements, we develop a two-dimensional axial-symmetric compositional simulator and subsequently use a commercial adaptive-implicit compositional simulator, CMG-GEM1. History matching of three field data sets acquired with probe-type formation testers in light-oil formations accurately reproduces measurements of sandface pressure, observation-probe pressure, GOR, and flow rate. Further, we demonstrate that history matching enables the detection and diagnosis of adverse data-acquisition conditions such as plugging, noisy data, and presence of OBM-filtrate invasion. We introduce a dimensionless fluid contamination function that relates GOR to fluid-sample quality. Sensitivity analysis of simulated fluid-sample quality to petrophysical properties clearly indicates that sample quality improves in the presence of anisotropy and impermeable shale boundaries. A computationally efficient dual-grid inversion algorithm is developed and tested on both synthetic and field data sets to estimate in-situ petrophysical properties from WFT measurements. These tests confirm the reliability and accuracy of the inversion technique. Results indicate that permeability estimates can be biased by noisy measurements as well as by uncertainty in flow rate, relative permeability, radial invasion length, formation damage, and location of bed boundaries. To quantify petrophysical and geometrical factors that can optimize the time of withdrawal of uncontaminated fluid samples, we compare the performance of focused and conventional probe-type WFT in the presence of mud-filtrate invasion. Simulations indicate a significant reduction in fluid-cleanup time when using a focused probe. The specific amount of improvement depends on probe geometry, fluid composition, and petrophysical properties of the probed formation. Finally, we develop an inversion method to estimate Brooks-Corey parametric saturation-dependent functions jointly from transient measurements of fractional flow and probe pressure. Results show that estimating Brooks-Corey parameters can be nonunique if the a-priori information about fluid and petrophysical properties is uncertain. However, we show that focused fluid sampling consistently improves both the accuracy and reliability of the estimated relative permeability and capillary pressure parametric functions with respect to estimates obtained with conventional-probe measurements.text
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Thanyamanta, Worakanok. "Evaluation of offshore drilling cuttings management technologies using multicriteria decision-making /." 2003.
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Sadiq, Rehan. "Drilling waste discharges in the marine environment : a risk based decision methodology /." 2001.
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Wu, Jianghui Torres-Verdín Carlos Sepehrnoori Kamy. "Numerical simulation of multi-phase mud filtrate invasion and inversion of formation tester data." 2004. http://wwwlib.umi.com/cr/utexas/fullcit?p3145882.
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Salazar, Luna Jesús Mauricio 1974. "Simulation and inversion of borehole electromagnetic measurements for the estimation of petrophysical properties in the presence of mud-filtrate invasion." Thesis, 2008. http://hdl.handle.net/2152/3940.
Full textAbstract:
Acoustic, electromagnetic (EM), and nuclear open-hole measurements are affected by fluids saturating near-wellbore porous and permeable rock formations, including hydrocarbons, water, and mud filtrate. Fluid invasion effects can be quantified and advantageously used to estimate petrophysical properties of the invaded rock formations. This dissertation incorporates the physics of water-base mud- (WBM) and oil-base mud- (OBM) filtrate invasion to the simulation and inversion of borehole EM measurements. We assume vertical boreholes penetrating clastic hydrocarbon- or water-bearing formations subject to either WBM- or OBM-filtrate invasion. The simulation of EM measurements in the presence of mud-filtrate invasion considers three different approaches: (1) piston-like invasion profiles, where we solely consider invaded- (flushed) and virgin- (uncontaminated) zones, (2) two-phase immiscible displacement and salt mixing between the invading WBM filtrate and connate water, and (3) invasion of single or multi-component OBM-filtrate into a formation saturated with multiple hydrocarbon components wherein the individual components are first-contact miscible. The last two approaches honor the physics of mudcake growth as well as the petrophysical properties that govern the process of multi-phase, multi-component fluid-flow displacement and include the presence of irreducible, capillary-bound and movable water. Electromagnetic measurements are simulated from spatial distributions of electrical resistivity calculated from the simulations of mud-filtrate invasion using clean- or shaly-sand water-saturationresistivity models. Inversion of petrophysical properties is posed as the nonlinear minimization of quadratic objective functions that quantify the misfit between EM measurements and their simulations. In the case of WBM piston-like invasion profiles in water-bearing formations, combined inversion of array-induction resistivity and spontaneous potential (SP) measurements yields connate water electrical resistivity and Archie’s cementation exponent. Permeability is calculated from the inversion of array-induction resistivity measurements assuming immiscible fluid-flow displacement of WBM into hydrocarbonbearing formations. Accurate reconstructions of layer-by-layer permeability are primarily constrained by the availability of a-priori information about time of invasion, rate of mud-filtrate invasion, overbalance pressure, capillary pressure, and relative permeability. This dissertation also quantifies the influence of petrophysical and fluid properties on borehole resistivity measurements acquired in the presence of compositional mixing of OBM filtrate invading partially hydrocarbon-saturated rock formations. Numerical simulations of OBM-filtrate invasion are performed with an adaptive-implicit compositional formulation that allows one to quantify the effects of additional components of mud-filtrate and native fluids on EM measurements. Perturbations of petrophysical and fluid properties enable the quantification of rock wettability changes due to OBM-filtrate invasion and their effect on the simulated induction resistivity measurements. Finally, simulations of induction resistivity measurements in the presence of OBM are compared to the corresponding measurements in the presence of WBMfiltrate invasion. The latter analysis allows us to estimate a realistic flow rate of OBMfiltrate invasion that is responsible for the variation of induction resistivity measurements as a function of their radial length of response. The combined simulation of the physics of mud-filtrate invasion and EM measurements provides reliable estimates of true formation resistivity and hence of water saturation, thereby improving the assessment of in-place hydrocarbons reserves.text
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Wu, Jianghui 1971. "Numerical simulation of multi-phase mud filtrate invasion and inversion of formation tester data." 2004. http://hdl.handle.net/2152/12818.
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Angeles, Boza Renzo Moisés 1978. "Simulation and interpretation of formation-tester measurements acquired in the presence of mud-filtrate invasion, multiphase flow, and deviated wellbores." 2009. http://hdl.handle.net/2152/18377.
Full textAbstract:
This dissertation implements three-dimensional numerical simulation models to interpret formation-tester measurements acquired at arbitrary angles of wellbore deviation. Simulations include the dynamic effects of mud-filtrate invasion and multi-phase flow. Likewise, they explicitly consider the asymmetric spatial distribution of water-base and oil-base mud filtrate in the near-wellbore region due to the interplay of viscous, gravity, and capillary forces. Specific problems considered by the dissertation are: (a) estimation of permeability from formation-tester measurements (pressure and fractional flow) affected by multi-phase flow and mud-filtrate invasion, (b) quantification of the spatial zone of response of transient measurements of pressure and fractional flow rate, (c) prediction of fluid-cleanup times during sampling operations in vertical and deviated wells, (d) joint inversion of formation-tester and resistivity measurements to estimate initial water saturation and permeability of multi-layer models, and (e) estimation of saturation-dependent relative permeability and capillary pressure using selective measurement weighting and Design-of-Experiment (DoE) methods to secure a reliable initial guess for nonlinear inversion. Using realistic tool and formation configurations, field measurements validate the reliability of the proposed methods. In one example, multi-layer rock formations are modeled using electrofacies derived from nuclear magnetic resonance logs, thereby reducing the number of unknown layer permeability values from 22 to 6. In the same example, non-uniqueness in the estimation of permeability is reduced with the quantitative integration of resistivity and formation-tester measurements. A second field example undertakes the estimation of permeability by history matching both pressure and gas-oil ratio (GOR) measurements acquired with a focused-sampling probe in a 27° deviated well. Because the latter measurements are affected by partial miscibility between oil-base mud and in-situ oil, Equation-of-State (EOS) simulations are used to account for variations of fluid viscosity, fluid compressibility, fluid density, and GOR during the processes of invasion and fluid pumpout. Results indicate that gravity-segregation and capillary-pressure effects become significant with increasing angles of wellbore deviation. If not accounted for, such effects could substantially degrade the estimation of permeability. Synthetic and field examples confirm that standard formation-tester interpretation techniques based on single-phase analytical solutions lead to biased estimations of permeability, especially in deviated wells or when complete fluid cleanup is not achieved during sampling. In addition, it is found that gravity-segregated invaded formations strongly affect predictions of fluid sampling time. Reliable and accurate estimations of petrophysical properties are only possible when both the angle of wellbore deviation and the process of mud-filtrate invasion are included in the interpretation methods.text
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Aka, Tiemele Wilfried Anderson. "Investigation of the effects of zinc oxide nanoparticles and synthesized cellulose nanocrystals (CNCs) on emulsion-based drilling fluids." Thesis, 2019. https://hdl.handle.net/10539/30622.
Full textAbstract:
A thesis submitted to the Faculty of Engineering and the Built Environment in fulfilment of the requirement for the Degree of Masters of Science, University of the Witwatersrand, Johannesburg, 2019Drilling Mud holds an important role in the drilling process in such a way that it is a determinant key to the success of the operation as well as the money spent throughout the process. Indeed the success and the cost of the operation can be severely impacted by some challenges experienced while drilling such as temperature and pressure conditions which leads to fluid loss, fluid deterioration...As a result there is a need to formulate a fluid with desirable rheological properties to withstand such undesirable parameters. Therefore this work was aimed to improve emulsion drilling fluids (EDFs) based nanoparticles with enhanced properties. Many investigations were performed to find a proper emulsion stability as well as a good drilling fluid performance. The stability of the prepared emulsion drilling fluids was done using surfactant with different concentrations for several days. After several days of preparation, the EDFs containing DTAB as surfactant have showed a better emulsion stabilizer compared to the Triton X-100 ones. In addition an investigation combining both NPs and surfactants confirmed the used of NPs to improve DF and revealed the effective use of ZnO NPs for drilling fluids application and preferentially with DTAB as surfactant. Following that result, the 2nd part of the work was based on the synthesis and characterization of CNCs as NPs to formulate EDF with DTAB as surfactant. The CNCs NPS were successfully obtained via the method of oxidation of microfibrillated cellulose through TEMPO-mediate and after characterization using TEM, spherical NPs with small size varying from 10-50nm were observed. The FANN® Model 35 viscometer served to display the behavior of the shear stress and viscosity of the prepared fluids against variable shear rate at variable NPs and temperature concentration. The rheological and filtration properties were increase with increase in CNCs content from 0.8 to 1.2% of fluid in room temperature and with an increase in temperature.
PH2021
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Kgwete, Maele Noma. "Investigation of the use of nanomaterial surfactants for oil emulsion drilling muds for deep-hole conditions." Thesis, 2018. https://hdl.handle.net/10539/26594.
Full textAbstract:
(MSc (50/50) Research Report in Oil and Gas Engineering)
School of Chemical and Metallurgical Engineering, Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, South Africa
September 2018The challenges faced by recovery methods for the extraction of oil and gas from reservoirs are related to existing drilling operations. Consequently, the muds become susceptible to poor heat transfer, disintegration, gelation, pipe sticking, poor cleaning ability, and poor lubrication. The challenges in drilling operations at high temperature and high pressure (HTHP) conditions can be mitigated when rheological properties are controlled and monitored. This research focusses on the investigation of the use of nanomaterial surfactants for oil emulsion (OBM) drilling muds in order to address the challenges in HTHP conditions. Emulsion drilling fluids with and without nanoparticle were prepared. ZnO nanoparticle was selected for this research based on its unique thermal stability properties. The drilling fluid package comprised 100 g of distilled water, 1 wt% of NaCl, 1 wt.% of CaCl2, various amount of surfactant (Triton® X-100 or DTAB) and + 6 wt.% of bentonite. The surfactant concentration varied from 0.25 to 1.25 % with 0.25 intervals. To evaluate and compare the contributions of surfactants and nanomaterial, the prepared drilling fluids were subject to rheological and filtration test. The results showed that DTAB surfactants-based drilling mud with ZnO nanoparticle showed a more stability compared to Triton. The decrease in viscosity with DTAB did not have a significant impact of the filtration loss in the presence of ZnO nanoparticles. The drilling fluids showed a dilatant and shear thickening behavior. The filtration test showed that 1 % of surfactant loss minimal amount of fluid and ZnO nanoparticle reduced the fluid lost capacity. The emulsion contained DTAB as surfactant and ZnO nanoparticle performs better in terms of retaining water and/or liquid in the mud; therefore, making it suitable for drilling at HTHP conditions.
E.R. 2019
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Lee, Hee Jae engineer. "Simulation and interpretation of formation-tester measurements acquired in the presence of mud-filtrate invasion and geomechanical deformation." 2008. http://hdl.handle.net/2152/18158.
Full textAbstract:
Wireline formation testers are widely used to measure in-situ fluid pressure, to retrieve reservoir fluid samples, and to estimate formation mobility. However, formation-tester measurements are invariably influenced by mud-filtrate invasion due to drilling overbalance pressure, thereby affecting the acquisition of uncontaminated fluid samples and the estimation of in-situ petrophysical properties. Moreover, in cases of stress-sensitive formations, rock mechanical deformation may take place due to the combined effects of in-situ stress, wellbore stress imposed by mud overbalance, and wellbore pressure exerted by the formation tester itself. The latter deformation causes near-borehole perturbations of porosity and permeability that are evidenced by pressure transients measured during build-up and shut-in stages of formation testing, especially when using dual-packer pressure probes. If unaccounted for, such perturbations can also bias the estimation of in-situ fluid and petrophysical properties. Conversely, the detection and quantification of elastic mechanical deformation effects on measured pressure transients can be used to infer the underlying rock elastic and petrophysical properties of the stressed formation. The purpose of this dissertation is twofold: (a) to quantify the relative effects of mud-filtrate invasion and geomechanical deformation on pressure-transient measurements acquired with dual-packer formation testers, with special emphasis on the appraisal of near-borehole porosity and permeability enhancement due to elastic mechanical deformation, and (b) to develop a new method to estimate elastic and petrophysical properties of rock formations from dual-packer pressure transients acquired in mechanically deformable rocks. Numerical simulations of mud-filtrate invasion are performed with an axialsymmetric two-phase (water-oil) method that enforces the specific boundary and source conditions of a wellbore that penetrates horizontal layers. Simulations are performed in a cylindrical system of coordinates using finite differences together with an implicit-pressure, explicit-saturation time-marching approach that also incorporates the dynamic conditions of immiscible mudcake growth due to filtration of solids at the wellbore. Laboratory experiments are conducted to further study pressure transients due to formation testing in the presence of invasion with water-base mud. Experiments include the effects of both mud circulation and mudcake on pressure-transient measurements and are performed on a variety of rock-core samples. Measurements are successfully validated with both the developed simulator and a commercial simulator, thereby lending credence to the assumed model of dynamic solid filtration. The developed mud-filtrate fluid-flow simulator is coupled with a finite-element code that assumes 2D axial-symmetric linear elasticity to quantify geomechanical deformation. Coupling of mechanical deformation with variations of porosity and permeability assumes a staggered-in-time, iteratively coupled volumetric model. We assume a dual-packer formation tester to quantify elastic deformation effects in stress-sensitive formations as a preamble to estimating in-situ elastic and petrophysical properties. It is shown that near-wellbore spatial variations of porosity and permeability due to mechanical deformation can bias the corresponding pressure-transient measurements acquired with the dual-packer formation-tester. The degree of biasing depends on the rigidity of the stressed formation. Finally, we develop a method to estimate in-situ petrophysical and elastic rock properties from pressure-transient measurements acquired with formation-testers in mechanically deformable rocks. Petrophysical and elastic properties will change in both time and space depending on the time evolution of the conditions that influence mechanical deformation. We use a commercial reservoir simulator to calculate pressure transients due to fluid pumpout in the presence of both invasion and mechanical deformation. A pre-stressed initial condition due to mud overbalance is assumed with incremental deformation due to surface force applied by the packers or probes, and active flow imposed by the formation-tester. In so doing, we consider pressure data sets acquired with both flow and observation probes during draw-down and build-up periods. For cases where a-priori information can be sufficiently constrained, our estimation method provides reliable and accurate estimates of petrophysical and elastic properties in the presence of moderate levels of random noise.text
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Jones, Christopher Robert. "Treatment of oily drill cuttings slurries using supercritical carbon dioxide." Master's thesis, 2010. http://hdl.handle.net/10048/1062.
Full textAbstract:
Thesis (M. Sc.)--University of Alberta, 2010.Title from pdf file main screen (viewed on June 30, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Environmental Engineering, Department of Civil and Environmental Engineering, University of Alberta. Includes bibliographical references.
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Vlad, Daniela. "Mudgases geochemistry and factors controlling their variability." Phd thesis, 2009. http://hdl.handle.net/10048/865.
Full textAbstract:
Thesis (Ph.D.)--University of Alberta, 2010.Title from PDF file main screen (viewed on Apr. 13, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Department of Earth and Atmospheric Sciences, University of Alberta. Includes bibliographical references.
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Kraussman, Andrew. "The Use of WBM to Improve ROP in HTHP/Hard Rock Environments." Thesis, 2011. http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9318.
Full textAbstract:
Modern day oil & gas well costs are driven by drilling performance as time becomes the dominant capital expense source. The ability to lower drilling costs becomes paramount when tight economic margins and high uncertainties/risk exist. Penetration rate decreases drastically in ultra deep formations, and substantial time is spent drilling the deepest section of these wells. Therefore, significant cost savings may be obtained through an improvement in penetration rate in deep formations. This paper shows that in HTHP (High Temperature High Pressure) hard shale/sand environments that PDC (Polycrystalline Diamond Compact) bits paired with water based mud experience 88% improvement in penetration rate than those paired with oil based mud. With this improvement in drilling rate, well costs can be substantially reduced making future ultra-deep hydrocarbon accumulations economically producible. Also observed was a drastic decrease in penetration rate in PDC bits with oil base mud which led to the use of diamond impreg bits, as the water base with PDC still maintained respectable penetration rates. The conventional penetration rate controls are still applicable in this case, but there exists a fundamental difference between the rock/fluid interactions of each mud type. Bit type, operating conditions, formation characteristics, and bit hydraulics are shown to not be the dominant influencing factor of this performance trend. The water base fluids examined have higher filtrate rates than the oil base fluids. However, a consistent data set of increasing filtrate rate corresponding to increasing penetration rate cannot be derived. Therefore filtration characteristics remain as a possible and partial influencing factor behind this data. Future experimental research is needed to confirm or disprove this theory. At this time the actual cause of this behavior is unknown, however the trend has been established showing water base drilling fluids performance versus oil base in the HTHP/hard rock environment.
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Xia, HONGWEI. "Investigation of Maximum Mud Pressure within Sand and Clay during Horizontal Directional Drilling." Thesis, 2009. http://hdl.handle.net/1974/1659.
Full textAbstract:
Horizontal Directional Drilling (HDD) has been used internationally for the trenchless installation of utility conduits and other infrastructure. However, the mud loss problem caused by excessive mud pressure in the borehole is still a challenge encountered by trenchless designers and contractors, especially when the drilling crosses through cohesionless material. Investigation of mud loss problem is necessary to apply HDD with greater confidence for installation of pipes and other infrastructure.
The main objectives of this research have been to investigate the maximum allowable mud pressure to prevent mud loss through finite element analysis and small scale and large scale laboratory experiments. The recent laboratory experiments on mud loss within sand are reported. Comparisons indicate that the finite element method provides an effective estimation of maximum mud pressure, and “state-of-the-art” design practice- the “Delft solution” overestimates the maximum mud pressure by more than 100%. The surface displacements exhibit a “bell” shape with the maximum surface displacement located around the center of the borehole based on the data interpreted using Particle Image Velocimetry (Geo-PIV) program.
A parametric study is carried out to investigate the effect of various parameters such as the coefficient of lateral earth pressure at rest K0 on the maximum allowable mud pressure within sand. An approximate equation is developed to facilitate design estimates of the maximum allowable mud pressure within sand.
A new approach is introduced to consider the effects of coefficient of lateral earth pressure at rest K0 on the blowout solution within clay. The evaluations using finite element method indicate that the new approach provides a better estimation of the maximum allowable mud pressure than the “Delft solution” in clay when initial ground stress state is anisotropic (K0 ≠1). Conclusion of this research and suggestions on future investigation are provided.Thesis (Ph.D, Civil Engineering) -- Queen's University, 2009-01-14 12:23:35.069
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Alotaibi, Mohammed Badri. "Characteristics and removal of filter cake formed by formate-based drilling mud." 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2800.
Full textAbstract:
Formate-based mud has been used to drill deep gas wells in Saudi Arabia since 2004.
This mud typically contains XC-polymer, starch, polyanionic cellulose, and a relatively
small amount of calcium carbonate particles, and is used to drill a deep sandstone
reservoir (310°F). Calcium carbonate particles are frequently used as weighting material
to maintain the pressure that is required for well control and minimize the leak-off. Such
solids become consolidated and trapped in the polymeric material and this makes the
filter cake a strong permeability barrier.
Various cleaning fluids were proposed to remove drilling mud filter cake;
including: solid-free formate brine and formate brine doped with organic acids (acetic,
formic, and citric acids), esters, and enzymes. The main objective of this research is to
assess the effectiveness of these cleaning fluids in removing drilling mud filter cake. A
dynamic high-pressure/high-temperature (HPHT) cell was used to determine
characteristics of the drilling mud filter cake. Drilling mud and completion fluids were
obtained from the field. Compatibility tests between potassium formate brine, cleaning fluids, and formation brine were performed at 300ºF and 200 psi using HPHT visual
cells. Surface tensions of various cleaning fluids were also measured at high
temperatures.
The conventional method for cleaning the filter cake is by circulating solid-free
formate brines at a high flow rate. This mechanical technique removes only the external
drilling fluid damage. Citric acid at 10 wt%, formic acid, and lactic acid were found to
be incompatible with formate brine at room temperature. However, these acids were
compatible with formate brine at temperatures greater than 122°F. Only acetic acid was
compatible with formate brine. A formula was developed that is compatible at room and
reservoir temperature. This formula was effective in removing filter cake. A corrosion
inhibitor was added to protect downhole tubulars. In general detail, this research will
discuss the development of this formula and all tests that led to its development.
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Sood, Shalu. "Displacement of drilling mud during primary cementing in near vertical oil wells." Thesis, 2004. http://hdl.handle.net/2429/15184.
Full textAbstract:
In this thesis, we consider the physical problem that stems from the industrial process of oil
well cementing during the well's construction. The laminar flow of non-Newtonian fluids in an
eccentric annuli has been the subject of many investigations. The work presented here is part of
a combined theoretical-experimental approach to the problem of non-Newtonian displacement.
An annular flow loop is constructed so that controlled experiments can be performed on fluid
displacements. We conduct a series of experiments using two different carbopol solutions. The
drilling muds are non-Newtonian in nature and exhibit a yield stress, we investigate the effects
of primary factors, i.e. eccentricity, inclination, density contrast, pH and concentration of
carbopol solutions on the displacement of two non- Newtonian fluids in an eccentric annulus.
From the experimental results, we classify the regimes of stable and unsteady displacements
qualitatively. We report a new phenomenon of flow bypass occurring for concentric cases. We
compare our experimental results with a simplified model which allows for a prediction of the
displacement flow type.
The lubrication model is not in good agreement with the experimental results.
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Zigmond, Brandon. "Experimental Analysis of Water Based Drilling Fluid Aging Processes at High Temperature and High Pressure Conditions." Thesis, 2012. http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11629.
Full textAbstract:
In efforts to render the safest, fastest, and most cost efficient drilling program for a high temperature and high pressure (HT/HP) well the maximization of drilling operational efficiencies is key. Designing an adequate, HT/HP well specific, drilling fluid is of most importance and a technological challenge that can greatly affect the outcome of the overall operational efficiency. It is necessary to have a sound fundamental understanding of the behavior that water-based muds (WBM) exhibit when exposed to HT/HP conditions. Therefore, in order to adequately design and treat a WBM for a HT/HP well specific drilling program, it is essential that the mud be evaluated at HT/HP conditions.
Currently, industry standard techniques used to evaluate WBM characteristics involve aging the fluid sample to a predetermined temperature, based on the anticipated bottom hole temperature (BHT), either statically or dynamically, for a predetermined length, then cooling and mixing the fluid and measuring its rheological properties at a significantly lower temperature. This, along with the fact that the fluid is not subjected to the anticipated bottom hole pressure (BHP) during or after the aging process, brings to question if the properties recorded are those that are truly experienced down-hole. Furthermore, these testing methods do not allow the user to effectively monitor the changes during the aging process.
The research in this thesis is focused on evaluating a high performance WBM and the current test procedures used to evaluate their validity. Experimental static and dynamic aging tests were developed for comparative analysis as well to offer a more accurate and precise method to evaluate the effects experienced by WBM when subjected to HT/HP conditions. The experimental tests developed enable the user to monitor and evaluate, in real-time, the rheological changes that occur during the aging of a WBM while being subjected to true BHT and BHP.
Detailed standard and experimental aging tests were conducted and suggest that the standard industry tests offer false rheological results with respect to true BHT and BHP. Furthermore, the experimental aging tests show that high pressure has a significant effect on the rheological properties of the WBM at elevated temperatures.