Transcripción del resumen del autor. Dynamic displacement experiments, simulating temperature and pressure conditions of an oil-bearing formation during primary production stage, were carried out to investigate the processes of asphaltene-induced precipitation and deposition during pressure depletion on a core sample and their effects on the absolute permeability. A representative monophasic-bottom-hole fluid sample and one core of consolidated Bedford limestone were used in coreflood tests. To identify the pressure and temperature conditions at which the asphaltene will begin to precipitate, as well as the bubble-point pressures of the reservoir fluid sample, the light-scattering technique solid detection system (SDS) using a variable volume, visual PVT cell was used. The coreflood test results indicated that the in situ asphaltene precipitation and deposition on porous medium damage absolute permeability and reduce effective porosity as reservoir fluid pressure is reduced until a point near bubble-point pressure. Core impairment, resulting from asphaltene deposition, was found to cause a 24% and 20% loss of initial oil permeability and effective porosity, respectively. A mathematical model, based on the transport of stable particulate suspensions in porous media, for asphaltene deposition was developed and validated directly with experimental results obtained in this investigation, as well as those found in the literature. On the basis of the developed mathematical model, two distinct mechanisms were identified as a consequence of the deposition process, namely, asphaltene adsorption and trapping. The porous medium was represented as a network of sites and bonds, with pore bodies identified as sites and pore throats as bonds. A satisfactory qualitative agreement was observed with the experimental results.

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