【作者】 李新禹；

【导师】 张于峰；

【作者基本信息】 天津大学 ， 热能工程， 2007， 博士

【摘要】 国家经济水平的提高,促进了社会生活的消费,伴随而来的是生活垃圾的大量增加,垃圾问题已经困扰着我们的世界。传统的垃圾处理方式或污染环境、或浪费土地和资源,因此开发新的垃圾处理方法与工艺势在必行。相比其他垃圾处理方式,垃圾热解法具有环境友好性强、能源化比例高、有较高的经济效益等优势,成为垃圾处理方法的新的研究课题。本研究的重点是无筛分城市垃圾热解实用技术和设备的研发。针对我国城市垃圾成分的特点,依靠垃圾自身热解产生的热量为热源,自行设计研制出日处理5吨垃圾的垃圾热解设备,完成全部运行调试工作。设备中主热解炉在起炉阶段使用煤碳作热源,运行后用垃圾自身热解后产生的垃圾碳作为热源。副热解炉利用主热解炉产生的热解气和烟气热作为热源,并有剩余的热解气作为能源输出,很好的完成了垃圾热解能源化和减量化的设计思想。在本文的热解设备的设计过程中,首次采用了外热式与内热式相结合、主热解炉与副热解炉耦合使用的具有连续工作能力的固定床垃圾热解设备。文中建立了城市垃圾热解数学模型,包括燃烧室、主热解炉和副热解炉的数学模型。利用多孔介质理论对混合垃圾的热物性进行了分析,取得较好的模拟效果。通过与垃圾热解理论研究结果的对比分析,得到了垃圾热解实用装置在热解温度、产气量和产气规律等方面的特性,为垃圾热解技术的实用化提供了可参考的理论依据。本文还针对城市垃圾的主要成分,从其分子结构出发,依据热重和微分热重(TG/DTG)曲线、工业分析和元素分析数据,详细分析了热解过程可能出现的相关化学反应,得出一些垃圾热解机理的模型。由此建立了生物质类和塑料类垃圾热解的动力模型,可应用该模型预测热解过程中任意时间或温度下原始成分试样和各阶段产物的质量随温度的变化情况,以指导和优化反应器的设计和运行。研究的结果证明,对于同一类物质尽管由于添加的成分有一定的区别,导致热解过程在温度和时间上有一些差别,但总的热解机理基本相似。热解温度范围和热解时间间隔相近,可以用同一个热解模型进行模拟,得到了令人满意的结果。更多还原

【Abstract】 With the development of the national economic level, the consumption in social life accelerated. However, what comes with the development is the increment of household solid waste (HSW) which already attained attentions from government, researcher, medium, et al. The traditional methods of household solid waste disposal may cause either the pollution to our environment, or occupy the soil and other resources., Therefore, to develop new method and technique for household solid waste disposal is impendence.Compared with other traditional disposal ways of household solid waste, the pyrolysis of HSW has many advantages, such as friendly environmental, high rate of energy exchanging and better financial benefit. It is becoming a new research domain for HSW disposal issue.The key point of this study is the practical technology and equipment of pyrolysis of HSW without sorting. According to the specific characteristics of the HSW component in the cities of China and relying on the energy that produced by itself-pyrolysis as the heat source, an equipment for the HSW pyrolysis which can deal with 5 tons of HSW was designed and erected, and all the circulation performances have been done. In this equipment, the coal is used as the heat source in the main pyrolysis furnace in the beginning section as well as the trash charcoal which was produced by the self-pyrolysis is used as the heat source in the circulation section.The auxiliary pyrolysis furnace uses the residual heat of pyrolysis gas produced by the main pyrolysis furnace as its heat source, and there is extra pyrolysis gas’s output which can be used as energy source. The whole process perfectly accomplished the design idea of the energy-dissipating and the waste-minimum of the HSW pyrolysis.In the process of this pyrolysis equipment design, a fixed-bed HSW pyrolysis equipment which has the continuous work ability and with the combination between externally heated and internally heated as well as the coupling usage between the main pyrolysis furnace and the auxiliary pyrolysis furnace are in present study had been considered for the first time. And the mathematical models of the HSW pyrolysis, including the mathematical models of firebox, main pyrolysis furnace and auxiliary pyrolysis were put forwarde. Fair good simulation effect has been obtained from the analysis of the thermophysical property of mixed HSW according to the cellular medium theory. Through the comparable analysis with the theoretic study of the HSW pyrolysis, the characteristics on pyrolysis temperature, volume producing and the orderliness of the volume producing of the HSW practical equipment are available now, and it provides a reliable theoretic gist in the practical use of HSW pyrolysis technology.To the component of MSW, from a molecule point of view, and according to the data of TG/DTG curve, industrial analyses and elemental analyses, some specific analyses about the chemical reaction which might be appeared in the pyrolysis procession deeply, also came to some MSW pyrogenation theory models. From above, the biology category and the plastic category of dynamical model were built, it can be used to forecast the original components and mass changes with temperature of production in every section under anytime or any temperature, with this, the design and the circulation of a reactor equipment could be supervised and optimized.As the result shows, for the same substance, although it could be a little bit different in its component, which probably may cause the differences in the temperature and time during a pyrolysis process, but all the pyrolysis mechanism is similarly the same. The pyrolysis temperature extension and its time separation are fairly close; they can be simulated under one same pyrolysis model and come out with satisfactory result.更多还原