Milind D Deo

Publications (4)5.33 Total impact

• Source

  Available from: Haibo Huang

  Article: Distribution of multiphase fluids in porous media: comparison between lattice Boltzmann modeling and micro-x-ray tomography.

  Michael C Sukop, Haibo Huang, Chen Luh Lin, Milind D Deo, Kyeongseok Oh, Jan D Miller
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  ABSTRACT: A parallel implementation of the three-dimensional Shan-and-Chen multicomponent, multiphase lattice Boltzmann method (LBM) was used to simulate the equilibrium distributions of two immiscible fluids in porous media. The simulations were successfully validated against cone-beam x-ray microtomographic data on the distribution of oil (decane), water, and air phases in a 5-mm cube of porous medium composed of packed quartz sand grains. The results confirm that LBM models allow for the straightforward incorporation of complex pore space geometry determined from x-ray microtomography measurements and that simulated wetting and nonwetting phase distributions are consistent with x-ray observations on both macroscopic and microscopic scales.
  Physical Review E 03/2008; 77(2 Pt 2):026710. · 2.26 Impact Factor
• Chapter: Near Infrared Spectroscopy to Study Asphaltene Aggregation in Solvents

  Kyeongseok Oh, Milind D. Deo
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  ABSTRACT: Petroleum asphaltenes are extremely complex and are difficult to characterize. Asphaltenes are a solubility class, defined as that portion of the oil (or organic material) that is soluble in toluene and insoluble in normal heptane. (Sometimes, other alkane solvents are used to define this solubility class, the most common other solvent being, normal pentane.) Asphaltenes present numerous problems during production, transportation, and processing of crude oils because they are on the higher polarity and molecular weight end of the crude oil compositional spectrum. As a result, this solubility class has been widely studied. There are over a thousand papers on various aspects of asphaltenes, including their chemistry, molecular weight, solubility, phase behavior, reactivity, etc.1-4
  11/2007: pages 469-488;
• Article: Asphaltene aggregation in organic solvents.

  Kyeongseok Oh, Terry A Ring, Milind D Deo
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  ABSTRACT: Asphaltenic solids formed in the Rangely field in the course of a carbon dioxide flood and heptane insolubles in the oil from the same field were used in this study. Four different solvents were used to dissolve the asphaltenes. Near-infrared (NIR) spectroscopy was used to determine the onset of asphaltene precipitation by heptane titration. When the onset values were plotted versus asphaltene concentrations, distinct break points (called critical aggregation concentrations (CAC) in this paper) were observed. CACs for the field asphaltenes dissolved in toluene, trichloroethylene, tetrahydrofuran, and pyridine occurred at concentrations of 3.0, 3.7, 5.0, and 8.2 g/l, respectively. CACs are observed at similar concentrations as critical micelle concentrations (CMC) for the asphaltenes in the solvents employed and can be interpreted to be the points at which rates of asphaltene aggregations change. CMC values of asphaltenes determined from surface tension measurements (in pyridine and TCE) were slightly higher than the CAC values measured by NIR onset measurements. The CAC for heptane-insoluble asphaltenes in toluene was 3.1 g/l. Thermal gravimetric analysis (TGA) and elemental compositions of the two asphaltenes showed that the H/C ratio of the heptane-insoluble asphaltenes was higher and molecular weight (measured by vapor pressure osmometry) was lower.
  Journal of Colloid and Interface Science 04/2004; 271(1):212-9. · 3.07 Impact Factor
• Article: Effect of Organic Additives on the Onset of Asphaltene Precipitation

  Kyeongseok Oh, Milind D. Deo
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  ABSTRACT: Onset of solid precipitation from oils was determined by identifying the minimum in near-infrared absorbance. Solvent-induced precipitation typically causes asphaltene precipitation, but is also known to cause high-molecular-weight waxes to come out of solution. The effects of the addition of solid saturated and unsaturated compounds on the onset of solvent-induced precipitation from a crude oil were examined. Crude oil from Rangely, an oil field in northwestern Colorado was used. The solvent-induced precipitation was brought about using pentane, hexane, and heptane. On the basis of limited solvent carbon number investigated (5−7), less solvent was required for precipitation onset as the carbon number of alkanes decreased. As the flow rate of the precipitant increased, the onset was delayed. Addition of solid n-alkanes, such as eicosane and tetracosane to the oil initially, accelerated the onset of precipitation. When solid polyaromatic compounds (naphthalene and phenanthrene) were dissolved in the oil, more solvent was required to initiate onset of precipitation. It was also shown that the crude oil was considerably undersaturated with respect to the asphaltenes and that initial dissolution of asphaltenes in the oil accelerated the precipitation. The data provided insight on solubility-related solids precipitation from oils.
  04/2002;