Chemical Conversion of Steel Mill Gases to Urea: An Analysis of Plant Capacity

A significant amount of global carbon dioxide emissions is due to steel mill gases. One promising approach for the reduction of these emissions is their chemical conversion. In this regard, the conversion to urea is very advantageous, since common urea processes are already using carbon dioxide as a feedstock. In the present paper, urea capacities are determined that can be realized using steel mill gases. The capacities are estimated based on new process concepts that are presented in this paper. Exemplarily, the steel mill of thyssenkrupp Steel in Duisburg, Germany, is considered. It could be shown that reasonable urea capacities can be reached. By this means, a great impact can be made on the reduction of steel mill carbon dioxide emissions. Considerable amount of carbon dioxide emissions are related with the steel production. In steel mills different gases are produced, which are currently used in power plants. The present work analyzes the potential of their use in urea plants. In this context, different cases are considered, which are compared with respect to carbon dioxide reduction and resulting urea plant capacity.