Formula Development And Properties Evaluation Of Surfactant-ploymer Flooding In Block Jing-11

After detailed analysis on the reservoir’s development history and characteristic,in accordance wim the characteristics of Block Jing-11:majorities of oil produced by water flooding,low oil viscosities,low acid value,relatively high content of reservoir clay minerals and low permeability,researches like determining the interfacial tension property,solution rheological property,phase stableness and chemical reagent adsorption and loss were conducted.Based on which,5 surfactants and 6 polymers were estimated and studied systematically.The optimum surfactants and polymers were selected and flooding system was built up.Furthermore,oil displacement efficiency of different multi-component chemical flooding system.The surfactants suitable for Block Jing-l1 is Gemini Surfactants;and the polymer is:partially hydrolyzed polyacrylamide polymer.Optimized ASP system is as follows:0.3%Gemini Surfactants+1500mg/Lpartially hydrolyzed polyacrylamide polymer.Best chemical injection placed in the reservoir temperature 60 days,the interfacial tension between the crude oil and the crude oil can still reach ultra-low,and the viscosity retention rate of the system is over 80%,which is less affected by environmental factors.The result of oil displacement efficiency tested by indoor physical modeling indicates:the EOR range resulted from ASP flooding can reach 24.1%.However,because surfactant is more sensitive to oil reservoirs and less surfactant,so it is necessary to synthesize amine oxide surfactant for the reservoir condition of Jing 11 block.The effects of the ratio of sample,the amount of catalyst,the reaction time and temperature on the synthesis reaction were studied.The structure and type of hydrophilic base of amine oxide surfactant were analyzed,which played an important role in surfactant oil water interfacial activity and emulsifying capacity.The interfacial tension between surfactant and crude oil is 10^-2mN/m,but it has stronger emulsifying action.When the concentration is0.05%,the oil recovery can be increased by 4.6%,and the oil recovery can be increased by22.5%.The result shows that the oil displacement capacity is second only to Gemini Surfactant.