Smart water displacement - an alternative enhanced oil recovery technique


Tezin Türü: Doktora

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Petrol ve Doğal Gaz Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2015

Öğrenci: CAN POLAT

Danışman: MAHMUT PARLAKTUNA

Özet:

The aim of this study is to investigate the effect of smart water displacement on oil recovery. The brine samples were prepared considering the characteristics of the samples proved to be effective in oil recovery. The effect of these brine samples on rock wettability was observed using Modified Flotation Test (MFT) procedure. The effect of changing brine salinity on interfacial tension between brine and oil samples was observed using interfacial tension meter and ring tensiometer. Liquids used in spontaneous imbibition and coreflooding experiments were determined considering the results of wettability and interfacial tension measurements. Flow was visualized under video camera and computer tomography (CT) was applied during the coreflooding experiments. The results indicate that using sulfate ion with divalent cations, Ca2+ and Mg2+ in low saline brine increases water wettability for carbonates and removing divalent cations from the brine samples increases water wettability for sandstones poor in clay content in comparison to wettability obtained with formation brine sample utilization. High water wettability can be achieved for carbonates even at low temperatures increasing the sulfate concentration. Improvement in spontaneous imbibition into the rock sample can be achieved decreasing the interfacial tension between brine oil using surfactant or decreasing the salinity of the brine sample, proved to be also effective in the core floooding experiment including flow visualization. In the core flooding experiment including the application of CT, it was observed that direct utilization of sulfated brine including divalent cations without injecting the high saline brine used to saturate the core sample previously resulted in more oil production.