Synergistic sustainability: Future potential of integrating produced water and CO₂ for enhanced carbon capture, utilization, and storage (CCUS)

Produced water (PW) and carbon dioxide (CO₂) are traditionally considered waste streams the oil and gas industry and other sectors generate. However, these waste products are examples of "waste to wealth" products with a dual nature of being valuable products or disposable byproducts. PW contains various elements and compounds that can be extracted and used in the manufacturing or chemical processing industry. Concentrated brine is generated from PW and can be used as feedstock in chemical processes. On the other hand, excess CO₂ produced in various industrial processes needs to be sequestered either through non-conversion processes, such as enhanced oil recovery and storage in geological formations, or through CO₂ conversion processes into fuels, polymers, and chemicals. While there is growing interest in reusing these products individually, no studies have explored the opportunities for producing additional chemicals or valuable products by combining CO₂ and PW waste streams (CO₂-PW). This study identifies the potential resources that can be generated by combining the beneficial reuse of PW and CO₂ conversion processes. CO₂-PW chemical conversion presents an opportunity to expand the carbon capture, utilization, and storage (CCUS) mix while reducing the environmental impact of disposing of these byproducts. The advantages of utilizing these waste streams for diverse applications are linked with the sustainable management of PW and decarbonization, contributing positively to a more responsible approach to resource management and climate change mitigation.