【作者】 宋宇；

【导师】 王文宇；

【作者基本信息】 哈尔滨工业大学 ， 建筑与土木工程， 2013， 硕士

【摘要】 当前我国的能源形势紧张，环境污染的问题日渐突出，近期出现的全国大范围“雾霾”天气，使人们对目前能源利用的状况更加担忧。所以本课题针对区域供热燃煤工业锅炉排烟温度仍然较高的情况，欲研究开发一套用于区域供热的燃煤工业锅炉尾部低温烟气余热回收系统，不但要回收烟气的显热，还要回收其中的潜热部分，达到节能的目的，缓解环境污染的压力。本文综合分析了燃煤工业锅炉的烟气排放特点，和困扰回收燃煤工业锅炉烟气潜热的一些主要因素，结合国内外烟气热能回收系统的经典案例，提出了一套烟气余热回收方案：烟气从锅炉的省煤器尾部流出后，首先经过除尘装置，然后相对洁净的烟气进入由耐腐蚀钢制成的间壁式低温烟气—空气换热器中，在换热器中烟气的温度可以降低到露点以下，释放出大量的汽化潜热，然后烟气由烟囱排出。在开发研究低温烟气—空气换热器的过程中，从换热元件的紧凑度、元件的结构特征和换热介质的流动形式等多方面考虑，选用波纹形的板片作为构成换热器的基本换热元件，换热介质采取逆流的流动方式，以增强换热；采用了流体模拟软件FLUENT，对不同板间间距的波纹形板片换热单元进行了换热分析和压降分析，最后确定了采用间距为6mm的波纹形板片作为换热的基本单元。对于在换热器内进行的换热过程，因为烟气的温度会降低到露点温度以下，烟气中的水蒸气会析出，不能用现有的换热系数计算公式，本文类比湿空气在表冷器中的热力过程，分析烟气在换热器中的换热过程，引入吸湿系数，计算换热器的传热系数，并以64MW锅炉为例，设计出了一套余热回收装置，然后对实际的工况进行模拟，并分析本套系统所能带来的社会和经济效益，为进一步利用燃煤工业锅炉尾部烟气的余热提供一些参考。更多还原

【Abstract】 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.更多还原