Oil production is a critical aspect of the global energy industry, and the increasing demand for hydrocarbons necessitates the optimization of oil recovery from mature reservoirs. The in-situ gel treatment is an effective method that enhances oil recovery by reducing the production of water. Despite the benefits of in-situ gel treatment, several challenges exist that may limit its effectiveness. One of these challenges is the possibility of polymer gel particles from production wells entering surface facilities. Its presence can be harmful to surface facilities. Despite the significant studies carried out in this field, several unresolved issues still remain that have not been addressed in the existing research. To address these challenges, This study presents an integrated approach, examining the effects of ultrasonic waves, chromium (III) ions, salinity, and retarders on partially hydrolyzed polyacrylamide (HPAM) gel degradation and their impact on oil-water separation in emulsions stabilized by HPAM aqueous solutions. The study aims to provide valuable insights for optimizing oil-water separation processes and gel degradation, with potential applications for various industries and environmental sustainability. The study's first part investigates the impact of ultrasonic waves on HPAM gel degradation, revealing that sonication time and salinity levels are crucial factors. Increased sonication time reduces residual gel, while higher salinity accelerates the process. The second part evaluates the influence of chromium (III) ions, salinity, and retarders on demulsification efficiency and oil separation in oil-water emulsions. The results indicate that the stability of emulsions may be influenced by chromium (III) ions. The choice of retarder and salinity conditions significantly affect oil separation rates. The third part introduces a novel method for removing gel from a mixture using ultrasonic waves and magnetic nanoparticles. The process involves degrading the polymer gel with ultrasonic waves and adding magnetic nanoparticles to the free polymer, which are then separated using a magnetic field. This integrated approach provides valuable insights for optimizing oil-water separation processes and gel degradation, with potential applications in various industries, such as food and petroleum, focusing on enhanced oil recovery and environmental sustainability. This study contributes to developing more efficient and sustainable strategies for oil production by addressing unresolved issues and exploring innovative gel removal methods.