【作者】 杨忠灿；

【导师】 倪明江； 李晓东；

【作者基本信息】 浙江大学 ， 工程热物理， 2003， 硕士

【摘要】 氯是生活垃圾焚烧中造成二次污染的重要元素之一，它的存在不仅会影响到垃圾焚烧炉的设计、运行和维护，而且会转化成HCl排放造成过热器腐蚀和大气污染。作为元素之一形成二噁英，以及影响重金属的迁移和分布。本文研究了垃圾焚烧中常见氯源的含氯量测定、氯向氯化氢转化的规律和机理，以及氯源对二噁英形成的影响等基础问题，并得到了一些有价值的研究成果。 文章首先分析了入炉垃圾中PVC类的主要赋存形态，常见塑料的用途和种类，选用有代表性的垃圾组分采用离子色谱法、硝酸银容量法和硫氰酸汞分光光度法测定垃圾组分含氯量，得到了常见垃圾组分的含氯量数据，确定了不同垃圾组分的含氯测定方法。利用小型管式炉，研究了有／无水蒸气的情况下快速升温时PVC、PCP和NaCl的HCl析出规律，回归分析了不同条件下的HCl析出情况。研究了垃圾中常见塑料类的热解和燃烧机理，根据其化学反应动力学分析方法，利用热天平进行典型含氯有机物PVC、PCP的燃烧过程中氯的析出研究，并求解其动力学参数。 选用煤和垃圾混烧的焚烧炉飞灰，研究了飞灰粒径分布对有机／无机氯源从头合成中二噁英生成的影响，以及不同无机氯源在从头合成中的相对作用。讨论了参加氯化反应的氯源，影响氯化反应的各种因素如飞灰特性、反应气氛以及铜、铁、硫等元素的作用，分析了气固两相中的氯化过程和铜、铁在氯化中的独特作用。利用固相氯化理论，分析了无机氯源在de novo合成中的氯化反应机理，并与有机氯源PVC的二噁英生成机理作了比较分析。 文章还研究了垃圾和煤混烧的流化床焚烧炉中氯源的输入量与HCl和二噁英排放的关系，并进行了炉内加钙时的脱硫脱氯研究，同时还研究了水膜除尘对二噁英的脱除效果。更多还原

【Abstract】 Chlorine is one of the important elements that can cause secondary pollution. For its existence design, operation and maintenance of municipal solid wastes incinerators(MSWI) will be greatly influenced; moreover corrosion of super heaters and contamination of air will be realized by HC1 converted from chlorine. In addition, chlorine is also one of components of dioxins and it can affect the shift and distribution of heavy metal. This paper will focus on such hotspots as determination of chlorine content in representative MSW, the mechanisms of chlorine being converted into HC1 and the effects on dioxins formation. Some valuable conclusions have been drawn.Chlorine contents of the representative composition of MSW are quantitatively analyzed by using silver nitride volumetric analysis (SNVA) method, mercury thiocyanate spectrophotometer (MTS) method and ion chromatography (IC) method etc, the results have been tabled and the determination methods are confirmed. Then emission characteristics of HC1 during incineration of PVC, PCP and NaCl in a pipe stove with or without water vapor are studied when their temperature is rapidly increased and the results are simulated by math formulas. In addition, pyrolysis and combustion mechanisms of representative plastics are discussed. According to chemical reaction kinetics HC1 emission in combustion of PVC and PCP is studied by thermal gravity analyzer and dynamics parameters are acquired.The effects of particle distribution of fly ash from a MSW incinerator on de novo formation of dioxins with the use of organic/inorganic chorine sources and the relative action of different chlorine sources in de novo formation are studied. Chlorine source for chlorination reaction, various factors of influencing chlorination such as characteristics of fly ash, atmosphere, and the roles of copper, iron, sulfur etc. are discussed. In addition, chlorination in gas and solid phases and special roles of copper and iron in chlorination are also analyzed. In terms of theories of chlorination in solid phase, chlorination mechanisms for inorganic chlorine in de novo reaction are studied and compared with formation mechanisms of dioxins from organic chlorine PVC.In this paper the relation between HC1 and dioxins emission and input of chlorine in a co-firing coal/MSWI CFB incinerator with MSW and coal cofired is studied, removal of sulfur and chlorine is talked over with Ca-base absorbents added directly in furnace, and the removal efficiency of dioxins through a wet scrubber is also investigated.更多还原