Study On Enhancing Oil Recovery By Air-Foam Flooding In Gu Dong Oilfield

Air-Foam flooding has two advantages both including air injection and foam injection. It is a new creative technique for enhanced oil recovery. It has two advantages including air injection and foam injection,so it integrates both functions of profile controlling and displacement. In the basis of analyzing the theories and experimental results,the paper sets five in detail oil displacement mechanism of Air-Foam. By experiments in laboratory,it is mainly study on static oxidation of crude oil and the blocking ability of air- foam and the factors which influence the efficiency of air-foam flooding and whether Gu west7 and Gu middle7 implement Air-Foam flooding technique for enhanced oil recovery The results from the data analysis demonstrate that: Gu crude oil low temperature oxidation occurs easily; oxidation rate increases and the quantity of oxygen consumed and carbon dioxide produced increases with the increasing of temperature and pressure; Some factors including of the ratio of gas to liquid,core permeability,foam injection means,residual polymer and so on influence on the blocking ability of air-foam system. The blocking ability of foam system is superlative when gas to liquid is in range 1:1 to 2:1 ; With core permeability increasing,resistance factor rises; The blocking ability of air-foam system the both slug of foam and air is the best among the two means of injection (both of foaming agents and air, alternating foaming agents and air);Residual polymer can enhance steady of air-foam system. Air-foam can effectively blocks the high permeability zone through controlling the gas mobility,and the displacement efficiency is increased by about 15.0%; On the basis of the theories and experimental results,air-foam flooding is a safe,effective,and promising technique for enhanced oil recovery of Gu west7 and Gu middle7.