The Simulation Experiment Research Of Alkyl-hydroxyl-sulfobetaines Flooding System

Alkyl-hydroxyl-sulfobetaines is a new type of amphoteric surfactant, it is used with superior performance: low irritation to skin and eyes; great surface activity in a wide range of pH; good stability to hard water,acid,alkali and various metal ions; when it is mixed with other surfactants, it shows great synergistic effects. It is widely used in daily chemicals,cosmetics and oil chemical fields.This paper is a performance study of viscoelastic surfactant alkyl-hydroxyl-sulfobetaines produced: DHSB,THSB,HHSB and OHSB, measuring surface tensions,interfacial tensions,rheology,viscosity,emulsification and step-down performance of polymer-surfactant system are evaluated. Experiment results indicate that the surfactant which has the smallest critical micelle concentration of these four active agents is OHSB, its cmc is 1.5mmol/L, the correspond surface tension is 26.0mN/m; the interfacial tension between crude oil from No.1 Oil Production Company of Daqing Oilfield Co.Ltd. and the binary system which is composed of alkyl-hydroxyl-sulfobetaines and middle molecular weight polymer (12,000,000~16,000,000) can reach 10-3mN/m among wide range of surfactant concentration; the stability of interfacial tension is better; the array surfactants have excellent characteristic of resisting hard water, the interfacial tension of the binary system which is composed of alkyl-hydroxyl-sulfobetaines can reach ultralow; emulsion which is composed of the binary system and the crude oil is stable and it has good emulsification effect; alkyl-hydroxyl-sulfobetaines solutions have rheology property, which can change the rheology of polymer solution, the concentration of alkyl-hydroxyl-sulfobetaines and carbon chain length can not affect the rheology much on the same kind of solution; alkyl-hydroxyl-sulfobetaines can augment viscosity of polymer-surfactant system over time and form a stable system with polymer.Additionally, analogue flooding effectiveness of activated water one system and surface-active agent and polyacrylamide binary system are systematically studied through physical simulation experiments. Physical simulation experiment results show that 2.0PV 0.3% alkyl-hydroxyl-sulfobetaines solution was injected after the water flooding,the flooding efficiency of surfactant is about 11.02% on average,the flooding efficiency of THSB is 12.21%, which has better effect, on the same condition, the flooding efficiency of SP (0.3%alkyl-hydroxyl-sulfobetaines, HPAM1200mg/L) flooding is higher than that of surfactant flooding under the same conditions,about 22.91%; in some extent, activate water can reduce the injection pressure, activate water flooding is a feasible approach towards reducing the injection pressure; SP injection pressure is higher than that of water flooding in a certain degree.