【作者】 王蓉；

【导师】 岑可法； 池作和；

【作者基本信息】 浙江大学 ， 工程热物理， 2005， 硕士

【摘要】 热重分析仪由于其精度高、试验方便、重复性好等优点,已逐渐成为国内外许多研究机构用来分析煤质燃烧和热解特性所经常采用的试验手段,并用来指导电站锅炉用煤。不同研究机构采用的仪器不同,得出的结果也有所不同,虽然许多文章对影响热天平试验过程和结果的因素进行了分析,但具体到针对煤这一试验样品方面仍然有所欠缺。 本文选用浙江省内电厂所经常采用的煤样,对煤的热失重特性进行了分析。通过对不同煤样在不同的试验条件下得到的热分析TG和DTG曲线,文章将煤粉燃烧过程的热失重曲线划分为三种线型,然后对热天平试验中所呈现的各种线型进行分析和研究,分析了试验条件对反应线型的影响。 另外本文还将不同煤种在热天平条件下进行热解,研究了煤中氮的热解析出特性,并且较为详细和系统地研究和分析了燃料N向挥发分N转化过程中受煤质、温度以及各种试验条件的影响,并对焦炭N含量的降低提出了控制方案。 此外针对国内某电厂200MW四角切圆燃烧锅炉,提出两种改造方案,并利用CFD软件平台对锅炉改造前后燃烧状况进行数值模拟研究,为实施再燃技术提供依据。更多还原

【Abstract】 The thermogravimetric apparatus has some advantages such as high precision , convenience , well-repetition characteristic etc. More and more research institutions make use of the experimental means to analyze the coal combustion characteristic, and apply it to supervise the usage of the coal in station boiler. There are different results made by different institutes because of the different apparatus. Many papers analyze the factors influencing the results, but have some deficiency in the aspects of coal samples.We select some coal samples which frequently used in the power plants in Zhengjiang province and analyze the heat agravic characteristic. TG and DTG curve of different coal samples can be got under different experiment conditions. The heat agravic curves of burning processions can be divided into three types in this paper. We discuss all kinds of the line types in these experiments thoroughly, and analyze the influences of the experiment conditions.This paper gives the property iodex, which can represent the pyrolytic property of pulverized coal and probes the factors affecting the pyrolysis of the pulverized coal, such as, the grain size of the pulverized coal, the heating velocity, etc.Coal reburning is a new technique to reduce nitrogen oxides (NO_X) emission. Numerical simulation of combustion process in a 200 MW tangentially fired furnace is performed on CFD software platform.更多还原