| dc.description.abstract | Surfactant of Methyl Ester Sulfonate (MES) is used to increase the yield of oil of the old well. Decreasing of interfacial tension values is obtained after the addition of NaCl alkali concentration of 0.5 % of water injection, after that MES surfactant was added at 0.3%, and were added by Na2CO3 alkali concentration of 0.1%, 0.2%, and 0.3%. The objective of the study was to know scale formation rate of formulation solution of MES surfactant. Scale is deposition occurred by reaction of compounds in the solution. Carbonate scale formation rate was observed from SI (stability index) and PTB (pounds per thousand barrels) which showed a negative value, so the surfactant formula solution was not saturated with CaCO3. Ranges of SI value were -2.88 mg/L to -0.39 mg/L and range of PTB value were 99.27 mol/l to -0.05 mol/l. The calculation result of solubility showed that CaSO4 and BaSO4 were dissolved properly, so that precipitation did not occur. Ranges of CaSO4 solubility were 403.34 meq/l to 34,400.99 meq/l and range of BaSO4 solubility were 0.54 meq/l to 367.62 meq/l. | en |
