Study on the application of a steam-foam drive profile modification technology for heavy oil reservoir development

This paper introduces a steam-foam drive pro-file modification technology for heavy oil development in Block Qi40 based on an in-depth study of the character-istics of heavy oil reservoir and cross flow characteristics of injected steam in Block Qi40 of Liaohe Oilfield. The per-formance evaluation was carried out indoors for foaming agents. Influencing factors affecting profile modification and foam injection mode selection are studied. The results show that the CX-4 foaming agent system has excellent foaming properties and foam stability at 300 degrees C. The plug-ging pressure difference of core can be increased by more than 15 times at 240 degrees C. When a 0.5 PV foaming agent system is injected, the oil displacement efficiency can reach more than 68%. The optimal concentration of the foaming agent is 0.5% and the change of resistance factor is the largest in the range of oil saturation between 15 and 20%. Foam has better plugging ability in high perme-ability and large pores. Furthermore, after field applica-tion effect analysis, it confirms that the steam-foam profile modification technology has an obvious effect on enhancing oil recovery.