The regenerative burner heats the room temperature air in a very short time. After the heated high temperature air enters the furnace, it entrains the flue gas in the surrounding furnace to form a thin oxygen-poor high-temperature air stream with an oxygen content of much less than 21%. At the same time, fuel is injected near the thin, high-temperature air, and the fuel is burned in the state of oxygen-lean (2%-20%). At the same time, the hot flue gas after combustion in the furnace is evacuated through another regenerative burner, and the sensible heat of the high-temperature flue gas is stored in another regenerative burner. The reversing valve with low operating temperature is switched at a certain frequency, and the commonly used switching cycle is 30 to 200 seconds. The two regenerative burners are in the alternate working state of heat storage and heat release, so as to achieve the purpose of energy saving.