【作者】 郑敏；

【导师】 赵虹； 杨建国；

【作者基本信息】 浙江大学 ， 工程热物理， 2007， 硕士

【摘要】 中国是目前世界上最大的煤炭生产国和消费国，也是世界上以煤为主要能源的大国，而且这种能源结构在今后相当长的时期内不会改变。我国现行煤炭资源的利用和转换有80％是通过燃烧而直接消耗并带来严重污染，因而如何提高煤的燃烧效率，研究煤粉的燃尽特性，找出影响燃尽效果的因素及改善煤燃尽性能的措施，对于燃用煤粉的燃烧设备来说，减少不完全燃烧损失，提高其燃烧效率将是十分有意义的。近年来，研究者通过不同的方法对煤粉的燃烧特性展开了大量的理论和试验研究，颇有成效，但是关于煤粉浓度及氧浓度变化下的煤粉燃烧特性的变化的研究很少。本文结合锅炉实际燃烧过程氧浓度、温度以及煤粉浓度变化等情况，运用德国Netzsch公司生产的NETZSCH STA449C型热天平模拟实际燃烧过程，对煤粉燃尽特性进行研究。本文选择无烟煤、温家梁、平朔5000、印尼Lati以及印尼TMG1作为不同煤化程度的煤的代表，利用热天平对掺配不同比例Al₂O₃的煤粉进行试验，通过分析燃烧过程TG-DTG曲线的变化讨论煤粉浓度变化对煤粉燃烧特性的影响。用动力学分析了煤粉浓度变化对活化能带来的变化，从化学反应的本质解释煤粉浓度变化对煤粉燃烧特性的影响。以热天平为试验平台，通过对无烟煤、平朔5000和阳泉三个煤种以恒温燃烧法进行氧浓度变化的热分析试验。研究氧浓度降低时，不同煤化程度煤种燃尽特性的变化，计算各煤种的单个煤粉颗粒在不同氧浓度下的燃烧速率，研究其变化规律。此外，根据锅炉实际燃烧过程中温度变化及氧浓度的变化情况，以无烟煤为主要研究对象，进行不同燃烧温度和不同样品质量工况下改变氧浓度的热重试验，分析温度、样品质量和氧浓度的变化对煤粉颗粒燃烧速率的影响规律，为进一步研究煤的实际燃烧过程提供基本的试验数据。更多还原

【Abstract】 China is the biggest coal production expense country in the world, particularly in the consumption of coal. Additionally this kind of energy structure couldn’t change in the long time ran. 80% of the coal resources is used through is the direct consumption, and it will bring up the serious pollution. Therefore, it is significant to enhance the combustion efficiency, analysis the burnout characteristic, find out the factors that could improve the burning performance. What’s more, it is particularly important to enhance its combustion efficiency and reduce the incomplete combustion of the combustion equipment. In recent years, theory and laboratory studies on the combustion characteristics have been conducted and yielded favorable results. However, the study on the change of combustion characteristics of coal under different coal concentration and oxygen concentration is rarely. According to the variation of oxygen concentration, burning temperature and coal concentration during the coal combustion in boiler, this paper will study the burnout characteristic of coal by simulating the combustion process using NETZSCH STA449C thermogravimetric analyzer.Anthracite, Wenjialiang, Pingshuo5000, Indonesia Lati and Indonesia TMG1 representing different rank coals were taken as the subject of study. These coals were mixed with different proportion Al₂O₃ and their combustion characteristics were investigated by analyzing TG-DTG curve. At the meantime, the activation energy was calculated in order to explain the effect on coal combustion characteristics which was brought by different coal concentration from chemical reaction essential aspect.The burnout characteristics of Anthracite, Pingshuo5000 and Yangquan were studied by using thermal gravitmetry in different oxygen concentration under constant temperature. After analyzing the burning rate of single particle of coal, the regularity was obtained. Moreover, Anthracite was taken as the chief subject of study. Its burnout characteristic was investigated with different burning temperature and sample mass under different oxygen concentration. The effort of burning temperature, sample mass and oxygen concentration on combustion rate of coal particle was analyzed, which provides fundamental experimental data for father study on the combustion process of coal.更多还原