The Laboratory Test of AOS and ABS Surfactant at 60oC for EOR Process

Background: By 2021, global oil demand is expected to rise by 5.3 million barrels per day (bopd), while oil output is anticipated to decrease gradually. The fall in oil production was attributed to a decline in reservoir pressure and a depletion of oil reserves in the field. Surfactants are employed as a technique in Enhanced Oil Recovery (EOR) to enhance the extraction of oil.

Objective: This study investigates two different forms of surfactant solutions, specifically AOS (alpha olefin sulfonate) and ABS (alkyl benzene sulfonate). The two surfactants were evaluated at five distinct concentration levels, specifically 5%, 6%, and 7%. Both have a salinity level of 7,000 parts per million (ppm). AOS and ABS were selected as research materials because to their capacity to decrease interfacial tension.

Method: A phase behavior test was conducted to assess the durability of the foam throughout a 21-day measurement period at a temperature of 60°C. In addition, the research also seeks to ascertain the efficacy of oil recovery from the surfactant solution under investigation.

Results: This study is a controlled experiment conducted in a laboratory setting to examine the effects of AOS and ABS surfactants on sandstone rocks. The AOS and ABS surfactant solution was prepared by combining AOS powder and 70% ABS surfactant liquid with brine containing a salinity concentration of 7,000 ppm. The research procedure comprises multiple stages, such as density testing and phase behavior testing.

Conclusion: Based on this study, it may be inferred that concentrations beyond 5% did not yield middle-phase emulsions. Nevertheless, the oil recovery rate escalated to 68% as a result of the water flooding injection test and ongoing surfactant injection.