煤自燃特性影响因素的试验研究

Experimental test and examination of the influential factors of the coal spontaneous combustion

影响煤炭自燃的因素较多,重点从煤的粒径、供氧浓度及供风量3个方面进行分析探讨,选取变质程度为中等的焦煤煤样为试验对象,利用矿井煤炭自燃测试装置,分别改变粒径、氧气体积分数和风量,研究其对煤炭自燃过程的影响,得出参数改变后煤炭与氧气反应生成气体的变化规律,并进一步分析气体变化的原因,从而有针对性地提出安全对策及措施。结果表明：当粒径大小为0.18~0.38 mm时,煤与氧气反应所生成的CO、CO_2的体积分数最大;当氧气的体积分数为8.20%时,所生成的CO、CO_2的体积分数明显比氧气体积分数为11.80%的小;而空气流量为100 m L/min时,气体产物的生成量最大。

To examine and test the phenomena of the coal spontaneous combustion and its influential factors,this paper has chosen the coking coal metamorphic medium of the variable parameters as coal sample. In the first place,what we would like to find is to determine the combustion characteristic features and identify the trends of the spontaneous combustion of the coal on the basic parameters of the corresponding kinds of coal through the coal industrial analysis and other kinds of elemental analyses. Secondly,what we have done is concentrated on the analysis of the effects of the coal particular features,including the particle sizes of the coal under test,the oxygen volume fraction and the air flow while the coal spontaneous combustion is going on. Thus,it can be seen that this paper intends to focus its attention on the coking coal metamorphic medium of the variable parameters,and the statusin-situ of the testing equipment and installation of the coal spontaneous combustion under exploration. On the other hand,the paper also wants to investigate the effects or influences of the variation of the particle sizes of coal,the oxygen volume fraction and the air flow on the process of the coal spontaneous combustion.Furthermore,we have also to discuss the kinds and features of the gas produced as a result of combustion along with the variation of the related parameters,which may account for the variation of the gas produced subsequently. Besides,the paper has also proposed measures to be taken for the specifical safety precaution as a result of the experiments,for particular significance has to be paid to the guard against the coal mine on-site fire prevention,and the control of the spontaneous combustion of the coal mine inside.And,finally,it is also necessary to point it out that the content concentration rates of CO and CO_2 produced in the coalmine are the biggest for the case of particle size within 0. 18-0. 38 mm.The concentration rates of the CO and CO_2 produced under the condition of 8. 2% of oxygen should be less than those for the case with 11. 8% of oxygen. And,simultaneously,the volume size of gas likely to produce can be greatest when the flowing rate of the air-gas mixture gets around 100 m L/min.