Application and Effect Evaluation of Different Types of Salt-Resistant Polymers in Daqing Oilfield

As oilfield development enters the middle and late stages, traditional polymer (HPAM) flooding technology faces challenges such as deteriorating reservoir properties and high salinity of formation water. Salt-resistant polymer (SR-HPAM) flooding technology has emerged as a solution. This study reviews the development of salt-resistant polymer flooding technology and analyzes its application status and development effects. By 2024, salt-resistant polymer flooding in Daqing Oilfield had cumulatively produced 9.886 million tons of oil, accounting for 42.6% of the annual polymer flooding production. Laboratory experiments show that salt-resistant polymers outperform conventional polymers in viscosity enhancement, stability, and viscoelasticity. Core flooding experiments indicate that salt-resistant polymers can achieve a higher increase in recovery rate by 1% point compared to conventional polymers, especially under conditions of high permeability and high molecular weight. Field application results show that the industrial promotion of TS800 salt-resistant polymer flooding can increase the recovery rate by 11.0–12.0% points. JD1200 salt-resistant polymer flooding has an earlier and longer low-water-cut period, increasing the recovery rate by 12.0–14.0% points and saving 29% of polymer usage under the same recovery rate conditions. LH2500 salt-resistant polymer flooding has a longer low-water-cut period, increasing the recovery rate by 13.0–15.0% points and saving over 15% of polymer usage. Salt-resistant polymer flooding technology has significant advantages in improving recovery rates and reducing production costs, providing strong support for the stable production of Daqing Oilfield [1, 2].