Abstract:

Well productivity can be significantly affected by the number of skin in the wellbore area. One of the alternative ways to solve the problem is oil well bore cleaning application by using methyl ester sulfonate (MES) surfactant. Surfactants need a carrying medium and in this study the utilization of diesel and biodiesel as a carrier was assessed. Surfactant was formulated with NaCl and aromatic solvents and its effect on interfacial tension (IFT), thermal stability, phase behaviour, and wettability alterationwere measured. The best oil-based surfactant solution was obtained from the formulation of 5% MES surfactant with 5% xylene inclusion to biodiesel as the carrying medium. This solution was then injected into an injection water which was already added in with 1% NaCl. It was found that biodiesel could be used as a substitute for diesel as a carrying medium in oil wellbore cleaning activity on well X as the resulted surfactant solution was able to maintain IFT values until day seven, form microemulsion with an IFT value of 1.12x10-2 dyne/cm, and alter wettability of rocks toward water-wet.

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