(88g) Predicting Nitrosamine Formation in Amine-Based Carbon Dioxide Capture Systems with Aspen Plus Simulation

Authors: 
Yu, K., University at Buffalo
Dai, N., Yale University
Carbon dioxide capture, the separation of carbon dioxide from fossil fuel-fired power plants, is a critical endeavor to mitigate global climate change. Currently, the most mature technology for carbon dioxide capture is amine-based absorption. However, this technology can also generate nitrosamines, a group of carcinogenic compounds, from the reactions between amines and nitrogen oxides present in the power plant flue gas. Public concerns for nitrosamines have impeded the implementation of carbon dioxide capture. The investigation of nitrosamine formation usually relies on experimental measurement of routine samples from carbon dioxide capture plants, which is difficult to test â??what ifâ? conditions.

In this study, a simulation module was developed to predict nitrosamine formation in industrial-scale carbon dioxide capture systems. Aspen Plus is currently the most widely used simulation software for predicting the carbon dioxide capture performance of industrial-scale systems. However, there is no available simulation module in Aspen Plus to assess the formation of nitrosamines. To develop a rigorous simulation module, potential chemical reactions associated with nitrosamine formation were integrated. A rate-based multi-stage simulation was performed with RadFrac block, incorporating heat and mass transfer correlations accounting for column characteristics and hydraulics. The simulation indicated that our module is able to estimate nitrosamine concentration as low as ppm level in the bulk solution. This simulation module offers a robust and efficient strategy to evaluate the risk of nitrosamine formation from carbon dioxide capture systems.