Best Practices-design for Scale Reduction During Produced Water Reinjection (PWRI)

Summary Water disposal treatment is one of the most important environmental challenges in oil industry. Produced water is hazardous because of its impurities, such as different type of salts, natural inorganic and organic materials, injected chemical and high salinity concentration. In spite of injectivity risks, environmental concerns force industry from surface discharge of produced water to produced water reinjection (PWRI), which is known as the method for produced water treatment. During PWRI, the most common problem is scaling which is highly affected by thermodynamic condition and water chemical composition. Thereafter, it is critical to identify influence of different variables and potential problems related to scales. In this study the OLI ScaleChem software was used to investigate the scaling problem. Results reveal that the common scales are strontium sulfide and calcite carbonate, and If EOR scenario is considered, one-order diluted refinery water is helpful while refinery water is a better candidate as IOR injection fluid.