Nonlinear Regression Analysis of Binary Flooding Recovery Influence Factors

Surfactant/polymer binary flooding is a development and improved oil recovery technology after ASP flooding. Nowadays, there is not only short of binary flooding industrial chemicals, but also the binary flooding mechanism and influencing factors are not studied in depth. Especially the premise of optimized mathematical methods to determine the relevance considering the interaction between all relevant factors has not been reported.

To better reveal the laws of binary(SP) oil flooding, based on the physical simulative experimental results of Berea core (400mD), the nonlinear regression method of the probability statistics theory and SPSS software was applied to conduct a weight analysis for the main influence factors of the binary oil flooding.

The results show that the three factors of the viscosity of binary system, the composite emulsifying index and the interfacial tension affect the chemical flooding recovery and the total recovery significantly. The results of the forced introduction method show that the reliability of the effect of the three factors on y₁, namely the chemical flooding recovery, is higher than 99%. The stepwise introduction method and the backward elimination method prove that the reliability of the effect of the three factors on y₂, namely the total recovery, is higher than 95%. The results also indicate that emulsification affects the binary chemical flooding recovery of moderately and highly penetrated sandstone cores more significantly.

The experimental and analysis results give very important guides for understanding the binary flooding mechanism and provide a theoretical basis for the application of binary oil flooding technology and the screening of the displacing agents.