Air-Foam Flooding Laboratory Experiments And Application In Low-Permeability Reservoirs

Air-foam flooding enhance oil recovery technology receives much concern in a related research area on account of its unique advantage.Foam has high selective plugging in the reservoir with high permeability channels,and effectively solve the profile control problem of the reservoir with strong heterogeneity.Meanwhile,foam can adjust and control the water-oil mobility ratio in the reservoir,and suitable for the high water-cut oilfield in the later stage of water flooding.Tang80 well region of Ganguyi oil field is a typical shallow low permeability oilfield and has made certain achievements in the air-foam flooding application.But there also exist some problems such as the unbalance of injection-production and wells in the high permeable zone has high water cut.In order to provide more reliable theoretical basis for the field application of air-foam flooding,it is necessary to carry out air-foam flooding experiment and adaptability study with the purpose of optimizing the foam fluid system formula and injection-production parametersOn the basis of foam formation and stability mechanism research results,foam system optimization experiment has been carried out for Tang80 well region of Ganguyi oil field.The experiment have studied the influence law of foam stabilizer,waste water,concentration and crude oil on the foam formation and stability.The experiment result shows that foam system of waste water has good feasibility,and oil can considerably weaken the combination property of foam system.Besides,the property of foam system is not correlate with the concentration of foam liquid and there exist optimal concentration range.The foam displacement experiment has been carried out in this paper to study the influence law of gas-liquid ratio,permeability,injection rate and oil saturation on the foam formation and stability.The experiment result shows that control the gas-liquid ratio between 3:1~4:1 is beneficial to enhanced oil recovery.Foam flooding has good selectivity of permeability and the blocking ability of foam enhanced with the increase of permeability.Besides,increasing injection rate can help to improve ultimate recovery and the timing of foam flooding shouldn't be too early.And it is better to turn to foam flooding after the water displacement recovery changed slightly.According to air-foam flooding development effect of Tang80 well region of Ganguyi oil field,this text optimize the injection and production parameters and evaluate the effect based on the study results.It has great significance for the application of foam flooding in the low-permeable reservoir.