Technological assessment of chemical metallurgical processes

The theory of exergy analysis is summarized. The basis for the selection of the concentration of a datum level species from which the standard chemical exergy is calculated is explained. The exergy balance equation is presented and the Law of Exergy Loss derived. Expressions are presented for a thermodynamic efficiency which is a measure of the performance of an industrial process relative to the ideal reversible process. The characteristic of energy and exergy are summarized. The theory is applied to the iron blast furnace and the results of analysis compared with results from the lead blast furnace. The iron blast furnace operates close to equilibrium in the stack region; hence the iron furnace is considerably more efficient in the thermodynamic sense. This is mainly a consequence of purity of the feed materials. This type of process assessment is not possible from an energy balance.