Variation of interfacial tension of the steam-foam drive in heavy oil reservoirs

Abstract

The reservoir could be divided into three zones: steam zone with saturated steam temperature, condensate zone and reservoir temperature zone. Experiments were conducted to investigate influence of mass fraction of foaming agent and temperature on interfacial tension at reservoir pressure and temperature, by means of high temperature and high pressure interfacial tension instrument. The results showed that increasing mass fraction of foaming agent and temperature would result in decreasing minimum dynamic interfacial tension and steady interfacial tension. As temperature increased, it would take less time for the system to reach minimum dynamic interfacial tension. In steam zone and condensate zone, the interfacial tensions between water and heavy oil all keep magnitude of 10-2mN/m, but it keeps magnitude of 10-1mN/m in reservoir temperature zone. So the foaming agent has better displacement efficiency for heavy oil in steam zone and condensate zone.