基于动力学的煤低温氧化机理研究

利用恒温反应实验装置,研究了煤低温氧化行为。根据CO2和CO气体解析过程特性,提出了煤低温氧化的两条途径,分别通过计算其反应活化能验证了这两条机理的存在性。研究了这两条机理在煤低温氧化过程中的不同的温度阶段所发挥的作用。结果表明:生成CO2的活化能很低,煤低温氧化很容易进行;CO的生成对温度有较高的敏感性。在温度低于70℃时,吸附途径在低温氧化过程中起主导作用,煤低温氧化主要生成CO2;当温度高于70℃时,燃烧途径起主导作用,煤低温氧化会产生大量CO。

Study on mechanism of low-temperature oxidation of coal based on reaction kinetics

The low-temperature oxidation of coal is the initial and necessary step of the coal spontaneous combustion.The different reactions take place at different temperatures.Using constant temperature reaction device,the behavior of low-temperature oxidation of coal was researched.According to the release characteristics of CO2 and CO,two pathways for the formation of CO2 and CO were put forward.The values of their activation energy were calculated,verifying the existence of two reaction mechanisms.And the roles of two mechanisms for the low-temperature oxidation were also investigated.The experimental results showed that the low-temperature oxidation easily performed,due to the low activation energy of CO2.The generation of CO is sensitive to the temperature.When the temperature is below 70℃,the low-temperature oxidation of coal is dominated by the chemisorption,with the main product of CO2.While the low-temperature oxidation of coal is dominated by the combustion when the temperature above 70℃,with the product of CO.