为研究不同含水率煤二次氧化时的自燃特性,使用1/3焦煤为研究对象,通过物理吸附、解析实验测试水分对煤空隙结构的影响,采用程序升温实验测试不同含水率煤初次、二次氧化自燃特征参数。研究表明:初次氧化后煤样孔结构主要以中孔为主,其孔体积和比表面积随着含水率的增加而增大;在前期,原煤样产生的CO气体浓度大于不同含水率的水浸煤样,与CO2变化趋势相反;二次氧化煤样的CO,CO2气体浓度和放热强度处于初次氧化原煤样和不同含水率煤样之间,从而表现出不同含水率煤样在初次氧化后,其氧化活性大于原煤样,小于初次不同含水率煤样的氧化活性。为避免水分对煤自燃的影响,应加强对煤在水分的条件下发生初次氧化后煤二次氧化自燃的检测和预防。
In order to research on spontaneous combustion properties of secondary oxidation of coal sam- ple after the coal initial oxidation with different moisture contents, physical adsorption experiments were carried out to research space structure of oxidized coal, temperature-programing experiments were carried out to study the spontaneous combustion characteristic parameters of initial and secondary oxidation of coal sample with 1/3 coking coal. It was found that after the coal initial oxidation, which mesoporous was oriented, and with the increase of moisture contents, both the total pore volumes and specific space area were gradually increased, as the result, CO concentration was greater than the different moisture con- tents' coal samples,as opposed to CO2 concentration in the earlier stage of the oxidized coal samples. The oxidized coal samples' heat releasing intensity and CO, CO2 concentration were between the initial coal and the initial coal with different moisture contents, which made clear that the oxidized coal' s oxid- ability was higher than the initial coal, and lower than the initial "coal of different moisture contents. In order to avoid the effect of moisture on spontaneous combustion of coal, the detect and prevention of the second oxidized coal spontaneous combustion after the initial oxidation under the different moisture contents should be strengthened.