Synthesis And Performance Evaluation Of Emulsified Viscosity Reducing Agent For Heavy Oil

There are abundant heavy oil resources in China,well development of such resources can be great help to solve the scarcity of petroleum resources.Some areas need emulsify and reduce viscosity to further enhance oil recovery,because it is difficult to effectively develop heavy oil from these regional and marginal wells.However,the emulsified viscosity reducer we use in recent years is with strong selectivity and poor stability.So it is necessary to design an amphiphilic emulsifier to make contribution to the EOR of oilfield.First,Synthesis amphiphilic emulsifier is designed according to the action principle of hydrophobicity/oil two affinity to promote emulsification,which uses(2-acrylamide)-2-methylpropanesulfonic acid,and laboratory-made hydrophobic monomers as monomers in the beginning.After that research optimizes the synthesis conditions and synthesizes the two kinds of amphoteric emulsion viscosity reducer by infrared spectroscopy.In the end,the experimental results confirmed the successful synthesis of emulsifier.Second,this research characterizes the solution properties of binary/ternary emulsifying viscosity reducers.The results showed that AS and ASA can associate to form a three-dimensional network structure.Both AS-2 and ASA-3 can effectively reduce surface tension in distilled water,and Shows the characteristics of pseudoplastic fluids and viscoelastic in distilled water and solution,among which the salt resistance,shear resistance and viscoelasticity of ASA-3 are better than AS-2.These two reducers have good viscosity of reducing effect under normal temperature(more than 97%),and the reducing effect of ASA-3 is 98%-99%.After analyzing and comparing the effects of emulsifier concentration,oil-water ratio,emulsification temperature,agitation strength,emulsification time as well as other factors on the effect of emulsification and viscosity reduction,both AS-2 and ASA-3 show better viscosity reduction and emulsion stability.The viscosity reduction effect of ASA-3 is better than that of AS-2,and the emulsification effect is the best when ASA-3 is used at a concentration of 4000 mg/L oil-water ratio of 5:5 emulsification temperature of 55?.AS-2 is at a concentration of 5000 mg/L.The best effect is to use a 4:6 oil/water ratio of 4:6 and an emulsification temperature of 50?.Finally,this research analyzes the practical applicationg of amphiphilic emulsifier through the core displacement experiment of large PV,including the comparation of commonly hydrophobically associating polymerAP-P4.The results show that under the comparison condition of oil displacement efficiency 100%,the recovery rate of AS A-3 is higher than that of the commonly used oil polymer polyacrylamide under the same experimental conditions.In summary,due to the unique lipophilic/hydrophilic properties of amphiphilic emulsifying viscosity reducer,this reducer can emulsify heavy oil effectively in porous media and maintain strong emulsifying stability,therefore,reducing the viscosity of crude oil,improving displacement pressure and increasing the wave capacity,so that the oil recovery can be improved.