Research And Development Of District Heating Boiler Of Low Temperature Flue Gas Heat Recovery System

China’s current energy situation and environmental pollution problems havebecome an increasingly prominent problem. The recent emergence of the national large-scale "Haze" Weather, make people pay more attention on the current energy situation.Therefore, based on this issue that coal-fired industrial boiler flue gas temperature isstill high, we want to make the research and development of district heating coal-firedindustrial boiler flue gas heat recovery system, not only to recover the sensible heat ofthe flue gas, but also to recycling wherein the portion of the latent heat. In order toachieve the purpose of energy saving. At the same time, reduce the environmentalpollution stress.This paper have analyzed the feature of coal-fired industrial boiler flue gas, and thedifficulty of latent heat recovery of boiler flue gas, combined with the classic flue gasheat recovery systems, proposed a set of flue gas waste heat recovery solutions. The gasfrom the economizer of the boiler, at first through the dust removal devices, and then themore clean flue gas go into the Low temperature gas-air heat exchanger, the temperatureof the flue gas can be reduced to below the dew point temperature, get a large amount oflatent heat of vaporization, then discharge the smoke from the chimney.In the process of developing the Low temperature gas-air heat exchanger, weconsider the factors as compactness of the heat exchanger element, and the flowingform of the medium in the heat transfer, and many other considerations. Using the wavesurface shape heat exchanger plates as the basic heat exchanger components, media takethe form of countercurrent to enhance heat transfer. Using a software named FLUENT,to analyze the temperature and the pressure of the different spacing for the heat transferplates.For the heat transfer process in the heat exchanger, because the temperature of theflue gas will be reduced to the dew point temperature, the water vapor in the flue gaswill precipitate and cannot use the existing heat transfer coefficient calculated equations.This paper compare with the thermodynamic process of the wet air in the surface cooler.To analyze the process of the gas in the heat exchanger heat transfer, the introduction ofmoisture absorption coefficient, calculated coefficient of heat exchangers, then simulatethe actual working conditions to, and analyze this system which can bring social and economic benefits. Provide some advices for the further use of coal-fired industrialboiler flue gas waste heat.