Oil Well Stimulation of Dispersion-Penetration Agent and Plugging Removal Technology

Area of Science:

• Petroleum Engineering
• Chemical Engineering
• Materials Science

Background:

• Conventional acidizing is ineffective against complex, organic-rich scales in oil wells.
• Strong organic solvents are costly and pose safety risks, limiting their field application.

Purpose of the Study:

• To develop and evaluate a low-cost, safe permeability-enhanced-dispersion (PD) technique for improved oil well scale removal.
• To assess the efficacy of a two-step PD pretreatment followed by acid flooding compared to direct acidizing.

Main Methods:

• Developed a PD fluid (DL) containing a dispersant, ethanol, surfactant blend, and self-generating acid.
• Evaluated the technique using compressed shale-oil scale cores, pressure decline, weight-loss measurements, and 3-D surface morphology.
• Conducted laboratory core-flood tests and a field pilot on Well H1.

Main Results:

• PD pretreatment increased acid dissolution power by approximately 20% and doubled overall dissolution efficiency.
• Generated multibranched etched channels, improving cleanup uniformity and oil recovery.
• Field pilot showed a significant increase in daily liquid production and oil addition.

Conclusions:

• The PD-acid sequence offers a fast, deep, and even damage-removal alternative to costly organic solvents.
• This technique is a safe and economical method for routine acidizing of homogeneous reservoirs.
• The PD technique shows strong potential for wider field adoption in oil well stimulation.