The Research And Application Of Salt And Temperature Resistant Viscosity Reducer For Heavy Oil

To reach the requirement of viscosity reducer for different application conditions, three kinds of surfactants, including carboxylate type surfactant, nonion-sulfate surfactant, and nonion-carboxylate type surfactant were synthesized by the saponifcation of oil resin, the reaction of polyoxyethylated castor oil (EL) and aminosulfonic acid as well as the reaction of OP and chloroacetic acid. Based on obtained surfactants, three viscosity reducer formulations were suggested. They are cheap salt and temperarutre Resistant viscosity reducer, high efficient salt tolerance viscosity reducer and temperature resistant viscosity reducer.(1) The temperature resistance of cheap viscosity reducer could reach 120℃, and calcium chloride tolerance could reach 500mg/L; with a mass percent of 0.5%, viscosity reducing ratio can reach 95%.(2) EL-60S made from EL-60 and aminosulfonic acid is suggested to be high efficient and salt resistant viscosity reducer. Using this reducer with mass percent from 0.1% to 0.2%, the viscosity reducing ratios for 7 different heavy oil samples are all above 95%。(3) To prepare a viscosity reducer with salt tolerance more than 2×10~5mg/L, EL-100S made from EL-100 is suggested to be compounded with a certain polymer. This formulation has been applied successfully in five wells of Northwest Company of SINOPEC.(4) Using acetone as solvent for reaction, OPC-8 is prepared from octyl-phenol-polyoxyethylene ether and chloroacetic acid, and is suggested to be temperature resistant viscosity reducer. With w(OPC-8)= 0.05%～0.15%, the viscosity reducing ratio of this surfactant for Shengli and Liaohe viscous crude all can be above 90%. In a addition, the temperature-resistant property of this viscosity reducer was studied. The results show that, the concentration of OPC-8 changed little after heated at 300oC for 3 hours.