Enhanced and improved oil recovery: Experimental and numerical studies of Asphaltene deposition
Organic and inorganic deposition, specially asphaltene precipitation, is a serious problem that occurs during asphaltic oil transportation from reservoir to wells and surface facilities. This phenomenon due to operational conditions of oil production disturbs the equilibrium condition of oil compositional. Several factors influence on the deposition of asphaltene such as variations in petrophysical properties of reservoir, oil composition, pressure, temperature, asphaltene and resin concentration, rate of oil production, gas-oil ratio and fluid flow regime. Permeability reduction, blockage and damage to the pipe lines, wells, wellhead infrastructure, surface facilities are some of the problems associated with the production from the reservoir containing asphaltic oil. Moreover, asphaltene deposition during enhanced oil recovery operations (e.g., water and gas injection) and during acidizing or well stimulation has the high possibility of occurrence. Therefore, performing compatibility tests, and conducting complete experimental studies to optimize the composition of injecting fluid, correction of operational conditions, adjustment of production and injection scenario, employment of the advanced techniques to control and reduce asphaltene deposition with the aim of prevention of reservoir damage, continuity and improvement of production are necessary.
Considering the severity of asphaltene deposition in majority of Iranian reservoirs, the oil and gas field development group has been investigating intensively on the impact of asphaltene deposition on oil production. The petroleum experts in oil and gas field development group have access to in-house and international laboratory and software and with respect to the aforementioned topic. The following subjects are some of the studies that currently under investigations.
Interpretation of field pressure, temperature, production tests to evaluate their effect on asphaltene deposition
Geochemical analysis of the drilling cuttings of source rock to determine the age, lithology, maturation process
SARA analysis, determination of asphaltene content and assessment of potential for asphaltene deposition at different zones of reservoir.
Determination of Asphaltene Onset Pressure (AOP) during natural depletion and water and gas injection scenarios.
Formation damage assessment due to asphaltene deposition during natural depletion and water and gas injection scenarios.
Evaluation of asphaltene inhibitors
Numerical modeling of asphaltene deposition in oil field reservoirs with consideration of reactive transport modeling and geochemical interactions.