A Dynamic Modelling Tool to Ensure the Safety of Drinking Water Sources Near Amine-Based CO2 Capture Plants

Abstract

Herein we present the development of a dynamic modelling tool intended to aid industries and regulators in the protection of drinking water sources located near amine-based CO2 capture plants. Risk is associated with carcinogenic and potentially carcinogenic nitrosamines (NSAs) and nitramines (NAs), respectively, that will form in the air from amines inevitably escaping the capture plant. These are very soluble molecules that can end up in drinking water sources such as lakes and groundwater basins. In Norway, a drinking water safety limit has been set for the sum of NSAs and NAs. Any ongoing CO2 capture activities must regulate their operations accordingly, i.e. to avoid exceedances of NSAs and NAs in nearby drinking water compartments. The modelling tool will assist in such regulations, by translating measured amine emissions at the stack to NSA and NA levels in a nearby water compartment. The tool will consist of a new atmospheric model which will be run together with a catchment model. The atmospheric simulations will be verified by in-situ plume measurements. Further improvements of the model accuracy will be achieved from laboratory experiments: 1) verifying atmospheric amine chemical reaction rates, and 2) assessing the biodegradability of the NAs. Finally, to make the advanced model available to the stakeholders, a web-based application will be developed. In the web-app, different settings, such as the application of water wash at the capture plant, can be adjusted to see directly the effect on the NSA and NA levels in a nearby lake or groundwater basin. By improving this tool and the associate knowledge base we aspire to contribute to the safe and cost-efficient implementation of amine-based CO2 capture technology.

Keywords: CO2 capture, amine degradation, nitrosamine, nitramine, environment, drinking water