Development and Performance Evaluation of Heavy Oil Viscosity Reducer for Drilling Fluid
Heavy oil with colloid,asphaltene and other substances can make heavy oil and drilling fluid filtrate form W/O emulsion,which increases the difficulty of heavy oil exploitation.In view of the above technical difficulties,a kind of heavy oil viscosity reducer JN-A for water-based drilling fluid was prepared with benzenediol,ethylene oxide,propylene oxide and chlorosulfonic acid as raw materials.And it was applied in water-based drilling fluid to evaluate the influence of heavy oil viscosity reducer JN-A on the viscosity of heavy oil.The experimental results showed that the filtrate of water-based drilling fluid formed emulsion with heavy oil,which increased the viscosity of heavy oil to 983.4 mPa·s.3%heavy oil viscosity reducer JN-A could reduce the viscosity of heavy oil to 75.1 mPa·s,and its viscosity reduction rate was up to 91.97%,showing excellent viscosity reduction effect.Heavy oil viscosity reducer JN-A could reduce the interfacial tension between filtrate and heavy oil to 0.51 mN·m-1,and it could reduce the adhesion of reservoir core pore throat to heavy oil and the flow resistance of heavy oil in pore throat,which was conducive to the exploitation of heavy oil reservoir.
Heavy oil viscosity reducerInterfacial tensionWettabilityFlow resistanceJamin effect