Project Introduction: Due to various factors such as coal type, design, and operation, the exhaust gas temperature of power station boilers and industrial boilers is generally high. In industries such as coal and petrochemical, steel, and building materials processing, there is a serious waste of low-grade energy in industrial furnaces. For power station boilers, installing a low-pressure economizer in the tail flue can effectively utilize the low-grade thermal energy of the exhaust gas for preheating cold air or feeding into the power plant's heating system, reducing standard coal consumption, saving energy, while ensuring safe operation of the unit, bringing In response to the aforementioned issues, our research group has developed a universal flue gas waste heat utilization system optimization design software, heat exchanger design verification software, condensing heat exchanger design verification software, rotary air preheater calculation software, and waste heat boiler performance calculation software. The prospects for the development and benefits of these results are as follows: The aforementioned software has been successfully applied in many domestic boiler manufacturing plants, electric power scientific research institutes (departments), electric power design institutes, etc., creating considerable economic benefits.