Biological and chemical treatment technologies for waste amines from CO capture plants.

Amine-based carbon dioxide capture is the most mature technology for reducing flue gas CO emissions. It has been postulated and observed during commercialisation of this technology that significant quantities of waste amines are produced. Further industrial implementation of this technology requires adequate disposal or valorisation options for this waste. This review presents an analysis of seven biological and chemical technologies for waste amine amelioration or valorisation. Of these, the biological treatments are identified as being more mature for industrial application with the capacity for marketable product generation. Slow speed is the main drawback of the biological processes but this does not hinder their commercial viability. Using waste amine for NOx reduction in power stations is a secondary option, where it seems probable that the amount of waste amine generated in the CO capture plant is sufficient to fulfil the DeNOx requirements of the flue gas. This route, however, requires investigation into the impact of waste amine impurities on the power station and the CO capture plant operations.