To provide an apparatus for generating hot blast, which substantially reduces CO2 gas released into the atmosphere, readily recovers CO2, achieves the miniaturization of a thermal storage combustion facility such as a blast pipe, an exhaust pipe, and the like provided for combustion air, and achieves the miniaturization of a pressure filling facility.

The apparatus for generating hot blast 10 includes a plurality of hot blast furnaces 12 each having both of the combustion chamber and thermal storage chamber, heats air 6 for blowing a blast furnace by one of the hot blast furnaces 12 to feed heated air 9 to the blast furnace 20, burns a blast furnace generation gas 1 discharged from the blast furnace 20 in a combustion chamber of another hot blast furnace 12 so as to cause a combustion gas, and directly heats the thermal storage chambers of the hot blast furnaces 12 by the combustion gas. The apparatus for generating hot blast includes: an exhaust gas circulation line 14 for recirculating a combustion exhaust gas 5 discharged from the thermal storage chamber to the combustion chamber of the hot blast furnace 12; and an oxygen injection device 16 for injecting oxygen 7 for combustion into the exhaust gas circulation line 14.