【作者】 卢珊珊；

【导师】 龚欣；

【作者基本信息】 华东理工大学 ， 化学工艺， 2011， 硕士

【摘要】 本文主要以粉煤加压气流床煤气化中试装置生成渣样以及Shell气化炉、宁煤GE废热锅炉生成飞灰为研究对象分析了气流床煤气化灰渣的特性。重点就粉煤加压气化中试装置生成渣样的可燃物含量,表观形态,粒度分布,矿物质组成以及渣中元素的迁移等特性进行深入的分析,探讨温度对这些因素的影响。另外,对飞灰的粘附行为开展了探索性研究。通过对渣中的可燃物含量和粒度分布的测定,发现粗渣和细渣中的可燃物含量有较大的差别,这与煤颗粒在气化炉内经历的路径不同有关。渣中的可燃物含量还与操作条件氧煤比以及煤种密切相关。氧煤比越高,可燃物含量就越低,颗粒的粒度也越大。原煤中部分元素的含量也会对可燃物含量和渣样的粒度造成较大影响。采用SEM, XRD, XRF, ICP-AES等分析手段对原煤以及渣样的表观形态,渣中的矿物质组成以及常量元素、痕量元素进行了分析。发现温度对这些因素有较大的影响：温度越高,渣样的表面越致密,渣中的矿物质的晶型会发生改变。温度对元素迁移尤其是痕量元素的迁移和富集有较大影响,痕量元素趋向于在低温渣样中富集。采用Fact-Sage热力学软件对气化过程元素的迁移过程进行模拟,并与实际的分析结果进行比较。为进一步了解痕量元素的行为提供依据。设计测定飞灰颗粒的粘附特性的实验装置,发现温度对飞灰的粘附特性同样具有较大的影响,在某一温度下颗粒的粘附性会大大增加。飞灰除了对材料具有粘附特性以外,还会对材料造成一定的腐蚀。更多还原

【Abstract】 The properties of the entrained flow gasification slag and fly ash are analyzed basing on the study of the pressurized entrained flow coal gasification pilot plant which produce slag and fly ash (Shell gasifier, the waste heat boiler of GE gasifier).The thesis gives a depth analysis on the characteristics of slag that generated from the coal gasification pilot plant, such as the content of combustible, the apparent shape, size distribution, composition of the mineral and the migration of elements in the slag, with the impact of temperature on these factors. In order to reveal the adhesion behavior of fly ash, the experimental setup about adhesion of fly ash is trying to be designed.By the determination of the combustibles content and the particle size distribution of the slag, it is found that there is great difference between the coarse slag and fine slag, which result from the different path. The coal particles come through the gasifier. The combustibles content has close relationship with the Residue in the fuel and operating conditions of the ratio of oxygen. And the coal and the kind of the coal. The higher the oxygen-coal ratio, the lower the fuel concentration, and more large the particle size. The content of some metals and S element in the coal will also greatly influent the combustibles content and the particle size of slag.The apparent form of the coal and slag samples, the mineral composition of slag, major elements and trace elements are analyzed by SEM, XRD, XRF, ICP-AES and other techniques. It is found that temperature has greater impact on these factors:the higher the temperature, the more thick the surface of the slag, and mineral crystal form will change. The temperature influence greatly on the element migration, especially on the migration of trace elements, trace elements tend to be enriched in the low-temperature slag. To imitate the behaviour of trace elements by Fact-Sage in the gasification. And compare the resualts with the experiments. This will provide the support for in-depth knowledge of trace element.Design experimental setup to determine the adhesion characteristics of fly ash. The temperature has great effect on the adhesion characteristic of fly ash, the particle adhesion will greatly increases at certain temperature.更多还原