Methodology to evaluate reduction limit of carbon dioxide emission and minimum exergy consumption for ironmaking

For evaluating theoretical reduction limit of carbon dioxide emission from a conventional carbon-based ironmaking, a new methodology of system analysis is proposed based on thermodynamics theory, together with implementation. In this method, we first define the ironmaking system by several fundamental reactions, then focus overall changes of enthalpy and exergy in the total system in order to obey first and second laws of thermodynamics, and finally derive carbon requirement and minimum exergy loss clearly. The results suggest the possibility of energy saving by indicating an ultimate goal for reducing CO2 emission and difference between operating data and it. Significantly, this method is also applicable to all other metallurgical or chemical systems for studying possibility and limitation of energy saving.