Advancements in the treatment of amine-rich wastewater from amine-based post-combustion carbon capture: a review

Abstract

Carbon capture and storage (CCS) plants play a pivotal role in reducing greenhouse gas emissions from carbon-intensive industries while enabling the continued use of fossil fuels. Among CCS methods, amine-based post-combustion capture is widely used for its efficiency and cost-effectiveness. However, the process generates substantial amine-rich wastewater containing harmful compounds like amines, ammonia, nitramines, sulfate, and nitrosamines, posing significant environmental and health challenges. This review examines recent developments in treating amine-rich wastewater, with a focus on economically viable and environmentally sustainable solutions. It discusses amine degradation pathways, byproduct toxicity, and the environmental impacts of untreated wastewater. By examining the physical, chemical, and biological technologies, biological processes, such as the pre-denitrification-nitrification process, stand out as effective and eco-friendly solutions for treating amine-rich wastewater. This study also proposes anaerobic ammonium oxidation (ANAMMOX) as a promising approach due to the low carbon-to-nitrogen ratio of CCS wastewater. A combined denitrification-anammox process is recommended to improve nitrogen removal efficiency by producing an ammonium- and bicarbonate-rich effluent that favors anammox bacterial growth. However, its effectiveness has not yet been evaluated, highlighting the need for further research. The conducted literature review also reveals that most existing research has focused on the removal of individual wastewater components rather than treating actual CCS wastewater, highlighting the need for integrated, scalable treatment approaches tailored to real CCS effluents.