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

Abstract

Conventional acidizing struggles to remove complex, organic-rich scales in oil wells, and while strong organic solvents can help, their high cost and safety risks limit field use. To overcome these shortcomings, we developed a low-cost, safe permeability-enhanced-dispersion (PD) technique that first loosens and disperses the scale and then applies acid for thorough cleanup. The PD fluid (DL) contains a mutually soluble fatty alcohol amide phosphate dispersant (DL-F), ethanol, a surfactant blend, and a self-generating acid. Shale-oil scale from the Chang 7 Member was compressed into cylindrical cores to mimic mixed (inorganic + organic) deposits, and a new two-step protocolPD pretreatment followed by acid floodingwas evaluated through pressure decline, weight-loss measurements, and 3-D surface morphology. Relative to direct acidizing, PD pretreatment increased acid dissolution power by ≈ 20%, doubled overall dissolution efficiency in core-flood tests, and generated multibranched etched channels that markedly improved cleanup uniformity. A field pilot on Well H1 (September 2024) confirmed laboratory findings: daily liquid production rose from 6.13 (47.7% water cut) to 11.95 m³ d^-1 (42.3% water cut) 6 months after treatment, adding ∼350 t of oil. These results demonstrate that the PD-acid sequence provides a fast, deep, and even damage-removal alternative to costly organic solvents, offering a safe, economical method for routine acidizing of homogeneous reservoirs and showing strong potential for wider field adoption.