Carbon dioxide (CO2) flooding is an EOR technique in which carbon dioxide is injected into the reservoir to improve the oil recovery. The reservoir oil and rock properties are altered when carbon dioxide interacts with the oil and rock present in the reservoir. Carbon dioxide injection alters the oil and rock properties by causing reduction in oil viscosity, oil swelling and wettability alteration of the rock. This paper will present a proposal to study the wettability alteration in carbonate formations during miscible carbon dioxide flooding. In miscible carbon dioxide flooding, the injection pressure of carbon dioxide would be kept above the minimum miscibility pressure. Thus carbon dioxide is miscible with the oil present in the reservoir. This paper primarily focuses on understanding the effect of crude oil composition on the change in wettability and asphaltene precipitation in carbonate rocks during miscible carbon dioxide flooding. Experiments will be carried out with different crude oils (Heavy, Medium and Light) on the same carbonate rock, at reservoir conditions, in order to observe the change in rock wettability. Interaction between formation and asphaltene would be investigated by measuring precipitation quantitiy into production recovery and rock at constant CO2 reservoir pressure. Carbonate rocks are very special due to the fact that usually carbonate rocks are oil wet and carbon dioxide tends to change the wettability of the carbonate rocks from oil wet to water wet. This change in wettability of the reservoir rock increases the oil recovery. Literature review revealed that considerable amount of research has not been done on the wettability alteration of carbonate rocks during miscible CO2 flooding process. Thus this topic needs to be further investigated and studied.
The response of floating stone columns of different lengths to diameter ratio (L/D = 0, 2, 4, 6, 8, and 10) ratios exposed to earthquake excitations is well modeled in this paper. Such stone column behavior is essential in the case of lateral displacement under an earthquake through the soft clay soil. ABAQUS software was used to simulate the behavior of stone columns in soft clayey soil using an axisymmetric finite element model. The behavior of stone column material has been modeled with a Drucker-Prager model. The soft soil material was modeled by the Mohr-Coulomb failure criterion assuming an elastic-perfectly plastic behavior. The floating stone columns were subjected to the El Centro earthquake, which had a magnitude of 7.1 an
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Dental casts come into direct contact with impression materials and other items that are contaminated by saliva and blood from a patient's mouth, leaving the casts susceptible to cross-contamination. The disinfectant solutions of the impression materials cause various adverse reactions. Therefore, disinfection of dental casts may be effective in preventing cross infection. This study was carried out to evaluate the surface hardness, dimensional accuracy, reproduction of details and surface porosity of type III, type IV and type IV extra hard dental stone after immersion in and spray by using SOLO and Sodium hypochlorite disinfectant solutions. Materials and methods: 240 Stone samples were prepared in rubber rings, A total of 60 test block w
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Background: Dental casts come into direct contact with impression materials and other items that are contaminated by saliva and blood from a patient's mouth, leaving the casts susceptible to cross-contamination. The disinfectant solutions of the impression materials cause various adverse reactions. Therefore, disinfection of dental casts may be effective in preventing cross infection. This study was carried out to evaluate the surface hardness, dimensional accuracy, reproduction of details and surface porosity of type III, type IV and type IV extra hard dental stone after immersion in and spray by using SOLO and Sodium hypochlorite disinfectant solutions. Materials and methods: 240 Stone samples were prepared in rubber rings, A total of 60
... Show MoreThis paper reports on the experimental study, which conducted a series of triaxial tests for the asphalt concrete using hydrated lime as a mineral additive. Three HMA mixes, prepared by the specification for wearing, levelling and base layers, were studied under three different temperatures. The test results have demonstrated that, compared with the control mixes excluding HL, the permanent deformation resistance of the HL modified mixes has significant improvement. The deformation has been reduced at the same load repetition number, meanwhile the flow number has been considerably increased. The degree of improvement in permanent deformation resistance using HL is more pronounced at high stress deviation states and high temperature.
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Hypothesis Nanofluid flooding has been identified as a promising method for enhanced oil recovery (EOR) and improved Carbon geo-sequestration (CGS). However, it is unclear how nanoparticles (NPs) influence the CO2-brine interfacial tension (γ), which is a key parameter in pore-to reservoirs-scale fluid dynamics, and consequently project success. The effects of pressure, temperature, salinity, and NPs concentration on CO2-silica (hydrophilic or hydrophobic) nanofluid γ was thus systematically investigated to understand the influence of nanofluid flooding on CO2 geo-storage. Experiments Pendant drop method was used to measure CO2/nanofluid γ at carbon storage conditions using high pressure-high temperature optical cell. Findings CO2/nano
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Permanent deformation, fatigue and thermal cracking are the three typical distresses of flexible pavement. Using hydrated lime (HL) into the conventional limestone mineral additive has been widely practiced, including in Europe, to improve the mechanical properties of hot mix asphalt (HMA) concrete and as the result the durability of the constructed pavement. Large number of experimental studies have been reported to find the optimum addition of HL for the improvement on HMA concrete mechanical properties, moisture susceptibility and fatigue resistance. Pavement in service is under complex thermomechanical stress-strain conditions due to coupled atmospheric and surrounding environment temperature variation and the traffic loading. To predic
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Surface wettability plays a significant role in determining the function of the wound dressing. They should have hydrophobic surfaces for the adsorption of bacteria and a hydrophilic surface necessary to improve cell attachment for most anchorage-dependent cell types. Furthermore, the Hydrophobicity / Hydrophilicity of the surface can be used to direct cellular processes such as cell initial correlation, adhesion, and migration during wound healing, as a result such surface can change its surface wettability which increases the dressing's usefulness.
In this research, nanomembres were prepared from polycaprolactone and chitosan solution (with different amounts of CS (0.05, 0.1, 0.2, and 0.4) % (w/w)) by the electrospinning m
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The presence of gypsum in soil as bonding agent alters its behavior with a large influence on itsphysical properties.Soil samples were taken from two locations of different gypsum content(S1 = 30.5% and S2= 20%) inMakhmur area. TheUnified soil classification system indicated that soil type was clay with low plasticity(CL). Basic methods of physical testing of soils, such as grain size analysis,specific gravity and atterberg limit were applied. Stabilizationof the gypsiferous soil was performed by addinglimestone waste powder takenfrom Said sadiqandPirmam areas,with different percentages(5%, 15%,25%).The results show that the addition of limestone powder to the tested soils decreases their liquid and plastic limits.
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