Produced Water Treatment and Reuse Options: Alternatives for Sustainable Water Resources

Water conservation and sustainability are of utmost importance in the Abu Dhabi Emirate, and they are considered key areas of strategic significance for the United Arab Emirates. The escalating demand for freshwater resources, coupled with the absence of a proportional rise in surface and groundwater supplies, necessitates the exploration of other water sources. Among these potential alternatives, produced water (PW) holds significant promise. Nevertheless, there is a lack of comprehensive characterization of the amounts of the generated produced water, as well as the quality and management of such water in the Abu Dhabi Emirate. The primary aim of this research was to study the amount and quality of produced water (PW) connected with the oil and gas sector, with the goal of evaluating its potential contribution to the water budget of Abu Dhabi Emirate. PW refers to the water that is naturally occurring in subsurface formations and is extracted to the surface during oil or gas production operations. The composition of the fluid may include water sourced from the reservoir, water that has been previously injected into the formation, and any chemical substances that have been incorporated throughout the various stages of production. The majority of PW has a significantly high salinity level and may consist of a combination of mineral salts, organic compounds, hydrocarbons, organic acids, waxes, and oils. Additionally, it may include inorganic metals, other inorganic components, naturally occurring radioactive material, chemical additives, as well as other constituents and byproducts. A comprehensive investigation was conducted to explore a multitude of viable management methods and treatment technologies aimed at mitigating salinity, which is recognized as a significant constraint in the usage of produced water. Furthermore, an examination was conducted on the origins, features, and magnitude of several contaminants present in the PW. In addition to total volumes produced, the water-to-oil ratio (WOR) from production activities was considered as this information can be used to evaluate the relative production age of resources within the production lifetime. On a global scale, the average PW production is around 280 million barrels per day, in contrast to the production of oil which stands at roughly 97 million barrels per day. This research included an update to the worldwide water-oil ratio (WOR) to a value of 4:1, indicating a water reduction of around 75%. The WOR ratio in the Gulf Cooperation Council countries has considerable heterogeneity, with an average value of 7:1. In this regard, it should be noted that the highest PW contributors are not always the most prolific producers of oil and gas.