Application of Ultraviolet, Ozone, and Advanced Oxidation Treatments to Washwaters To Destroy Nitrosamines, Nitramines, Amines, and Aldehydes Formed during Amine-Based Carbon Capture

Although amine-based CO2 absorption is a leading contender for full-scale postcombustion CO2 capture at power plants, concerns have been raised about the potential release of carcinogenic N-nitrosamines and N-nitramines formed by reaction of exhaust gas NO x with the amines. Experiments with a laboratory-scale pilot unit suggested that washwater units meant to scrub contaminants from absorber unit exhaust could potentially serve as a source of N-nitrosamines via reactions of residual NO x with amines accumulating in the washwater. Dosage requirements for the continuous treatment of the washwater recycle line with ultraviolet (UV) light for destruction of N-nitrosamines and N-nitramines, and with ozone or hydroxyl radical-based advanced oxidation processes (AOPs) for destruction of amines and aldehydes, were evaluated. Although