Preventing Asphaltene Deposition in Oil Reservoirs by Early Water Injection

Abstract

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractA comprehensive modeling and simulation of asphaltene precipitation and deposition in petroleum reservoirs is carried out. The effects of the asphaltene deposition on reservoir properties, and the productivity of the vertical and horizontal wells during primary oil recovery are demonstrated. An early water-injection development scheme for suppressing asphaltene deposition is proposed and its feasibility is investigated by means of simulation. The performance of the early water-injection development scheme is compared with the direct depletion development scheme.The results indicate that the early water-injection not only increases the oil recovery significantly but also extends the economic production life of the reservoir considerably.

Investigating the Effect of CO2Flooding on Asphaltenic Oil Recovery and Reservoir Wettability

“…The Wang and Civian solubility model is used. This model predicts the volume fraction of asphaltene precipitated during pressure depletion and as a function of the temperature.…”

“…This model predicts the volume fraction of asphaltene precipitated during pressure depletion and as a function of the temperature. In this work, the effect of the temperature and pressure on asphaltene precipitation is estimated using Wang and Civian X A = α 1 + α 2 P + α 3 P 2 + α 4 P 3 + α 5 T + α 6 P T + α 7 P 2 T + α 8 T 2 + α 9 P T 2 + α 10 T 3 where α 1 −α 10 are constants of the polynomial model.…”

Impact of Asphaltene Precipitation and Deposition on Wettability and Permeability

“…Due to the many limitations of existing permeability impairment models, the gradual surface adsorption and pore blockage models to account for the permeability reduction in sandstone were developed. 2 Comparisons of results from these models to the true permeability, as well as Wang and Civan's model, 3 relate temperature and mechanism dependent parameters with a physical process such as asphaltene deposition.…”

Asphaltene Deposition Preference and Permeability Reduction Mechanisms in Oil Reservoirs: Evidence from Combining X-ray Microtomography with Fluorescence Microscopy

“…Changes in the pressure, temperature, and oil composition during acid stimulation, natural depletion, and CO 2 injection may lead to asphaltene deposition in oil reservoirs, causing a significant reduction in reservoir permeability and productivity. − Extensive knowledge of asphaltene deposition and its impact on formation permeability is essential for development scheme formulation, reservoir performance evaluation, reservoir damage mitigation, and remediation. , …”

“…1−3 Extensive knowledge of asphaltene deposition and its impact on formation permeability is essential for development scheme formulation, reservoir performance evaluation, reservoir damage mitigation, and remediation. 4,5 Asphaltene deposition is due to a combined effect of several processes, such as asphaltene association, flocculation, precipitation, and adsorption. 6,7 To date, the three primary asphaltene deposition research focuses are the onset condition of asphaltene deposition, the amount of asphaltene deposition, and its influence on the reservoir permeability.…”