Hot blast stoves typically require about 3 GJ/t-HM and account for about one third of the enrgy needed to make iron and around 10–20% of the total energy demand in integrated steel works. The efficiency of the hot stoves can be improved by recovering the heat from the flue gases of the stoves (having typical temperatures of around 250 ^oC (Worrell, 2010. et al., p. 87);and using this energy to pre-heat the combustion fuel and/or the air entering the stoves. Besides stove flue gases, other heat sources, such as that arising from sinter cooling, can be used for this purpose. While also reducing the need and costs for natural, or any other enriched, gas, pre-heating with waste heat increases the oeverall stove efficiency by up to 8% (IEA, 2007. p.126). Recuperated heat from BF stoves can also be used to preheat the BF air itself, or to heat the gas and/or combustion air used for boilers and other heating systems located in close proximity. For each application, the system and control requirements will be different and the final system should be selected based on fuel reduction potential and cost effectiveness. In most cases one of these options is justifiable.

   This option is regarded to have medium application potential in China and India, and low potential for the United States.