炭化粉自燃氧化规律研究

Study on spontaneous combustion oxidation of carbonized powder

为了对煤质活性炭生产过程中的副产物炭化粉的氧化特性进行研究,采集生产所用的原煤和炭化粉,采用扫描电镜实验、氮吸附实验、热重实验、傅里叶变换红外光谱实验及非线性热动力学方法,对样品的孔径结构、特征温度、活性官能团及表观活化能的变化进行分析计算。结果表明:经过炭化工序处理,炭化粉的孔径结构和比表面积较之原煤更为发达;在同一升温速率下,炭化粉着火点温度和氧化速率最大点温度均低于原煤;炭化粉中脂肪烃、部分含氧官能团及芳香烃含量较之原煤减少,羟基含量增大;炭化粉的表观活化能小于原煤。综合分析表明,炭化工序可导致炭化粉的氧化自燃性增高,研究结果可为炭化粉自燃的防治与综合利用提供理论依据。

In order to study the oxidation characteristics of the by-product carbonized powder in the production process of coal activated carbon,the raw coal and carbonized powder used in production were collected,and by scanning electron microscope experiment,nitrogen adsorption experiment,thermogravimetric experiment,Fourier transform infrared spectrum experiment and nonlinear thermodynamics method,the pore size structure,characteristic temperature,active functional group and apparent activation energy of the samples were analyzed and calculated.The results show that the pore structure and specific surface area of carbonized powder are more developed than that of raw coal;at the same heating rate,the temperature at the ignition point and the temperature at the maximum oxidation rate of carbonized powder are lower than that of raw coal;compared with the raw coal,the content of aliphatic hydrocarbon,some oxygen-containing functional groups and aromatic hydrocarbon in carbonized powder decrease,while the content of hydroxyl increase;the apparent activation energy of carbonized powder is lower than the raw coal.The comprehensive analysis shows that the carbonization process can lead to the improvement of the oxidation spontaneous combustion of carbonized powder,the research results can provide theoretical basis for the prevention and comprehensive utilization of the spontaneous combustion of carbonized powder.