Oil recovery performance of a modified HAPAM with lower hydrophobicity, higher molecular weight: A comparative study with conventional HAPAM, HPAM

Abstract

Adaptability in improving hydrophobically associating polyacrylamide (HAPAM) flooding by reducing hydrophobicity (to decrease retention) while increasing molecular weight (to ensure viscosity), was researched by the comparative study of an accordingly modified HAPAM (M-HAPAM), a conventional HAPAM (C-HAPAM) and a classical hydrolyzed polyacrylamide (HPAM). Attention is paid to their thickening ability, injectivity and propagation, retention, and finally oil-displacing performance. Results show that hydrophobicity reduction helps retention decrement and propagation enhancement of M-HAPAM, making it outperform C-HAPAM with regard to injectivity, propagation, and oil recovery: however, HPAM works best at permeabilities of ∼1μm2∼3μm2, and M-HAPAM needs more hydrophobicity reduction.