The first pilot test of polyacrylamide microsphere alternate surfactant flood(PMAS)with mixtures of anionic-cationic surfactants(Sa/c)was carried out for a high-temperature,high-salinity,and highhardness sandstone res...The first pilot test of polyacrylamide microsphere alternate surfactant flood(PMAS)with mixtures of anionic-cationic surfactants(Sa/c)was carried out for a high-temperature,high-salinity,and highhardness sandstone reservoir to demonstrate the potential of this novel technique to improve oil recovery.A critical micelle concentration(CMC)of 4.82 mg/L,an ultralow interfacial tension(IFT)of 8104 mN/m,and a high oil solubilization of 22 were obtained.Static and dynamic adsorptions of Sa/c on natural core containing 15 wt%clay were reduced to about 2.20 and 0.30 mg/g-core,respectively,with the addition of adsorption inhibitor(AI).Since June 2014,the pilot test of PMAS was carried out in a Sinopec reservoir with a temperature of 87C,a salinity of 260,393 mg/L,and a hardness of 6,401 mg/L.Twelve cycles of alternative injection of 0.0125 PV Sa/c with a concentration of 0.1%and 0.0125 PV polyacrylamide microsphere with a concentration of 0.2%were conducted at an injection rate of 0.1 PV/yr,for a total of 0.3 PV chemical injection.As a result,the net daily oil production increased from 0 t to 6.5 t,and the water cut decreased from 96.3%to 93.8%,leading to an ultimate improved oil recovery of 6.3%original oil-in-place.展开更多
文摘The first pilot test of polyacrylamide microsphere alternate surfactant flood(PMAS)with mixtures of anionic-cationic surfactants(Sa/c)was carried out for a high-temperature,high-salinity,and highhardness sandstone reservoir to demonstrate the potential of this novel technique to improve oil recovery.A critical micelle concentration(CMC)of 4.82 mg/L,an ultralow interfacial tension(IFT)of 8104 mN/m,and a high oil solubilization of 22 were obtained.Static and dynamic adsorptions of Sa/c on natural core containing 15 wt%clay were reduced to about 2.20 and 0.30 mg/g-core,respectively,with the addition of adsorption inhibitor(AI).Since June 2014,the pilot test of PMAS was carried out in a Sinopec reservoir with a temperature of 87C,a salinity of 260,393 mg/L,and a hardness of 6,401 mg/L.Twelve cycles of alternative injection of 0.0125 PV Sa/c with a concentration of 0.1%and 0.0125 PV polyacrylamide microsphere with a concentration of 0.2%were conducted at an injection rate of 0.1 PV/yr,for a total of 0.3 PV chemical injection.As a result,the net daily oil production increased from 0 t to 6.5 t,and the water cut decreased from 96.3%to 93.8%,leading to an ultimate improved oil recovery of 6.3%original oil-in-place.
