Produced water (PW) is considered to be the largest source of industrial wastewater associated with oil and gas extraction operations for industrial production. It is a mixture of organic and inorganic compounds that has high complexity in terms of various characteristics. Globally, the volume of PW is increasing along with the expansion of gas and oil fields, leading to major impacts on the environment. Existing treatment technologies involve partially treating the PW through removing the suspended solids, heavy metals, without removing organic components and re-injecting the water underground using water disposal injection wells. The treatment process consists of a primary treatment unit to remove the particles, followed a secondary biological or chemical processing treatment, while the final treatment stage involves the use of a tertiary treatment unit to improve the water quality and remove the remainder of the undesired components. Moreover, while PW is considered one of the available options to be utilized as a water source, no alternate advanced treatment options on a commercial scale are available at present due to the limitations of existing PW treatment technologies, associated with their maintainability, sustainability, cost, and level of quality improvement. As such, research focused on finding an optimal treatment approach to improve the overall process continues to be conducted, with the aim of reusing the water instead of injecting it underground. This literature review discusses the latest advanced technologies for PW treatment aimed at reusing the full stream capacity of PW and eliminating the need for wastewater disposal via injection. It is concluded that researchers should focus on hybrid treatment technologies in order to remove the pollutants from PW, effectively allowing for its reuse.
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