为了掌握煤经多次氧化的自燃特性指标参数,对气肥煤、1/3焦煤、贫煤和无烟煤4种不同变质程度煤的煤样进行预处理,即将原煤样经过升温氧化后利用氮气冷却至常温,得其氧化煤样。采用煤质分析实验、物理吸附实验和煤自燃程序升温实验,对两次氧化过程中的耗氧速率、放热强度、CO产生率和特征温度等自燃特性参数进行对比实验研究。结果表明,2次程序升温过程中,煤样的自燃特性参数都随煤温呈指数变化规律。氧化煤样的耗氧速率、放热强度和CO产生率均表现出在氧化反应前期大于原煤样,氧化反应后期小于原煤样;自然发火的特征温度低于原煤样,说明氧化煤样更容易发生自燃,危险性较大。
To control multiple oxidation of coal and spontaneous combustion of oxidized-coals,and grasp the characteristics of oxidized-coals,experimental study is adopted to test the characteristic parameters of raw coal and oxidized-coal. To pre-treat four different ranks of gas-fat coal,1 /3 coking coal,lean coal and anthracite with heating treatment,and cooling down to room temperature with nitrogen. Coal quality analysis,physical adsorption experiment and temperature-programmed experiment are adopted to test the oxygen consumption rate,CO production rate,heat intensity,and other characteristic parameters of coals during two oxidation processes. The results shows,during two temperature-programming processes,the characteristic parameters are changed with temperature as exponential form. Compared with the raw coals,the oxygen consumption rate,CO production rate and heat intensity of oxidized-coals amplify at early stage of oxidation,and decline at later stage. The characteristic temperatures of oxidize-coals are lower than the raw coals,there are conclusions that the oxidized-coals are prone to fire and have a severe hazard to environment.