Foam flooding is an effective oil displacement technique to improve fluid sweep efficiency and increase oil recovery. The objective of this study is to investigate the application of air-foam for heavy oil recovery under heterogeneous reservoir conditions. The paper first investigated the air-foam flow behavior in porous media and identified the effects of different factors such as gas-liquid ratio, injection rate, and crude oil saturation on air-foam resistance. Then, dual-tube sand-packs were used to evaluate the performance of air-foam for heavy oil recovery from heterogeneous reservoir conditions. The results indicated that the air-foam could divert the fluid from the high-permeability zone to the low-permeability zone, decrease the water cut and improve the oil recovery. Further studies revealed that there existed an optimal reservoir permeability contrast ratio in air-foam flooding for heavy oil recovery. The air foam performance for oil recovery would be reduced beyond or below this permeability contrast ratio. Finally, field tests on air-foam for heavy oil recover demonstrated that air foam flooding could increase heavy oil production rate and decrease the production water cut.
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