The exhaust treatment system primarily includes a combustion chamber, secondary combustion chamber, waste heat boiler, and an air cooler. After combustion in the secondary combustion chamber, the regenerative flue gas is denitrified at 1100°C and then its heat is recovered by the waste heat boiler. The waste heat boiler can be equipped with multiple interfaces as needed for heat recovery, such as steam drying, heating in dormitories, bathing, kitchen warming, or selling excess heat. This effectively saves energy and achieves full utilization of resources.