Screening of the Effective Additive to Inhibit Surfactin from Forming Precipitation with Divalent Cations for Surfactin Enhanced Oil Recovery

Energies

卷:13

Kyuro Sasaki¹  Yuichi Sugai¹  Nao Miyazaki²  Yoshifumi Okamoto³  Satohiro Yanagisawa³ 

[1] Department of Earth Resources Engineering, Faculty of Engineering, Kyushu University, Fukuoka 8190395, Japan;

[2] Department of Earth Resources Engineering, Graduate School of Engineering, Kyushu University, Fukuoka 8190395, Japan;

[3] New Business Development Department, Corporate Research & Business Division, Kaneka Corporation, Osaka 5308288, Japan;

关键词: enhanced oil recovery;    surfactin;    divalent cation;    citric acid;    precipitation;    interfacial tension;   

DOI  :  10.3390/en13102430

来源: DOAJ

【 摘 要 】

Surfactin, which is an anionic bio-surfactant, can be effective for enhanced oil recovery because it decreases interfacial tension between oil and water. However, it forms precipitation by binding with divalent cations. This study examined the countermeasure to prevent surfactin from forming precipitation for applying it to enhanced oil recovery. Alcohols, chelating agents, a cationic surfactant and an ion capturing substance were selected as the candidates for inhibiting surfactin from forming precipitation. Citric acid and trisodium citrate were selected as promising candidates through the measurements of turbidity of the mixture of the candidate, surfactin and calcium ions. Those chemicals also had a function as a co-surfactant for surfactin. However, the permeability of the Berea sandstone core into which the solution containing surfactin and trisodium citrate was injected was decreased significantly, whereas citric acid could be injected into the core without significant permeability reduction. Citric acid was therefore selected as the best inhibitor and subjected to the core flooding experiments. High enhancement of oil recovery of 9.4% (vs. original oil in place (OOIP)) was obtained and pressure drop was not increased during the injection of surfactin and citric acid. Those results suggest that citric acid has a dual role as the binding inhibitor and co-surfactant for surfactin.

【 授权许可】

Unknown