长期水浸风干焦煤自燃特性及参数实验研究

发布时间：2018-05-07 02:06

本文选题：煤自燃 + 水浸焦煤　；参考：《太原理工大学》2017年硕士论文

【摘要】：煤自燃是危害煤矿安全生产的主要自然灾害之一。由于地质复杂,中国地下煤矿很多采空区存在水浸泡问题,采空区大量残煤、遗煤长时间浸泡在水中,当由于自然和人为的因素影响下,煤中水分被排除后,往往能在采空区迅速形成一个较大的自燃区域,且其自燃比未经浸泡原煤更加剧烈,常规灭火措施很难控制。经过长期水浸溶胀的煤体其物理化学特性会发生很大改变,其低温氧化特性较原煤差异较大。当前对于长期水浸煤体自燃特性变化缺乏系统研究,因此,对于长期水浸煤体其自燃特性和微观结构的改变具有重要意义。为了探究焦煤长期水浸风干后其自燃特性和参数的变化,本文选用西曲矿4#煤为研究对象,在实验室通过程序升温、比表面积与孔隙分析、红外光谱分析等探究焦煤物理化学性质变化,并设计小型煤自燃模拟平台完成水浸焦煤风干煤体自燃模拟过程。实验表明:水浸风干焦煤煤体形成了更多的孔隙和裂隙,孔直径和比表面积随浸泡时间的增加而增加,煤中原生孔隙和裂隙更加致密均匀,煤与氧气接触面积增大,能够加快焦煤氧化自燃;长期浸泡后,煤分子中有利于煤自燃的活性基团-OH、-CH_3、-CH_2-等增多,焦煤更容易与空气发生反应;程序升温实验表明,氧化过程中耗氧速率增大,在升温过程会产生更多的CO、CO_2等氧化产物,但增加幅度会逐渐减小,水浸风干焦煤随浸泡时间增加其活化能降低,自燃倾向性增强,自燃特性随浸泡时间增加有一定程度的增强;通过小型煤自燃模拟平台对焦煤原煤和水浸30天焦煤进行煤低温氧化实验,分析焦煤低温氧化过程温度分布和气体组成成分表明,长期水浸焦煤在低温氧化过程中更容易氧化,反应更加剧烈,其耗氧速率和氧化产物CO、CO_2、C_2H_4等氧化产物明显高于焦煤原煤。总体而言,经过长期水浸风干焦煤其自燃特性增强。
[Abstract]:Spontaneous combustion of coal is one of the main natural disasters endangering the safety of coal mine production. Because of the complicated geology, there are many problems in the goaf of underground coal mine in China. There are a lot of residual coal in the goaf, and the coal is soaked in the water for a long time. When the water is excluded from the coal, it is often able to form a rapid formation in the goaf. The larger self ignition area, and its spontaneous combustion is more severe than untreated coal, the conventional fire extinguishing measures are difficult to control. The physical and chemical properties of the coal body after long-term water soaking will change greatly, and its low temperature oxidation characteristic is more different than that of the raw coal. In order to explore the spontaneous combustion characteristics and the change of the microstructure of the long-term water immersed coal, in order to explore the spontaneous combustion characteristics and the change of the parameters of the coal coking coal, the 4# coal is selected as the research object. The physical and chemical properties of the coking coal are investigated by program heating in the laboratory, the specific surface area and pore analysis, and the infrared spectrum analysis. The experimental results show that the pore diameter and specific surface area increase with the increase of soaking time, and the primary pores and cracks in coal are more compact and even, and the contact area of coal and oxygen increases. When the coal molecules are soaked in a long period of time, the coal molecules are beneficial to the spontaneous combustion of coal, such as -OH, -CH_3, -CH_2- and so on. The coking coal is more likely to react with the air. The temperature programmed experiment shows that the oxygen consumption rate increases during the oxidation process, and more CO, CO_2 and other oxidation products will be produced in the process of heating, but the increase will gradually increase. As the soaking time increases, the activation energy is reduced, the tendency of spontaneous combustion is increased and the spontaneous combustion characteristic increases with the soaking time. The low temperature oxidation experiment of coking coal and 30 days coking coal is carried out by the small coal spontaneous combustion simulation platform. The temperature distribution and gas composition of coking coal at low temperature oxidation process are analyzed. The composition shows that the long-term water immersed coking coal is easier to oxidize in the process of low temperature oxidation, and the reaction is more intense. The oxygen consumption rate and oxidation products CO, CO_2, C_2H_4 and other oxidation products are obviously higher than coke coal raw coal. In general, the spontaneous combustion characteristics of the coal by long-term water immersion wind dry coking coal are enhanced.

【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD752.2

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