Performance evaluation of a novel stable foam in high-temperature and high-salinity reservoir of the Shengli Oilfield

In high-temperature and high-salinity (HTHS) reservoirs, the performance of chemicals used in enhanced oil recovery (EOR) technology will be significantly affected by the temperature and salinity of formation water, resulting in the ineffective effect of chemicals. To solve the problem of low recovery in HTHS reservoirs, a new foam J4F6 was prepared. First of all, seven kinds of surfactant with good foam performance were selected on the base of widely used surfactants. Then matched the quality proportion of surfactant following the design, under the same conditions to evaluate their foaming performance and the ability to reduce the interfacial tension (IFT), J4F6 with the best performance was selected and then the concentration, NaCl, and Ca2+, temperature, aging time, and adsorption loss on the foaming performance were investigated. Finally, a sandpack flooding experiment was carried out to study the flow characteristics and resistance factor (RF) of J4F6. The results showed that J4F6 has the high strength adjustment and flooding ability of traditional foam. In addition, it has strong temperature and salt resistance, which can greatly improve the swept zone and oil displacement efficiency of HTHS reservoir and enhance oil recovery. This study can provide a reference value for EOR of HTHS reservoir.