High Temperature Air Combustion (HiTAC) Phenomena and its Thermodynamics

Abstract

The fundamentals and thermodynamic analysis of High Temperature Air Combustion (HiTAC) technology is presented with focus on industrial furnaces as they are amongst the major energy users. The HiTAC is characterized by high temperature of combustion air having low oxygen concentration. This study provides a theoretical analysis of HiTAC a process from the thermodynamic point of view. The results demonstrate the possibilities of reducing thermodynamic irreversibility of combustion by considering an oxygen-deficient combustion process that utilizes both gas- and heat-recirculation. Furthermore, combustion with the use of oxygen (in place of air) is also analyzed. The results showed that a system which utilizes oxygen as an oxidizer results in higher 1st and 2nd law efficiencies as compared to the case with air as the oxidizer. This study is aimed at providing technical guidance to further improve efficiency of a combustion process which show very small temperature increases due to mild chemical reactions. The significant of these findings are now widely used in industrial furnaces with singular successes on energy savings, pollution reduction and reduced size of the equipment. The exergy analysis too can be used as a technical tool to improve efficiency in combustion processes.