水分对堆积状态褐煤自燃特性影响研究

为研究水分对低阶煤在堆积状态下自然发火特性的影响,基于Frank-Kamenetskii理论,采用开放式恒温加热试验法,分析不同水分含量(4％～23％)白音华褐煤的升温过程及临界自燃着火温度.进一步研究不同煤样粒径(0.5～5 mm)和煤堆体积(1.25 ～10 ×105 mm3)条件下,水分对堆积褐煤自燃特性的影响....

Study on influence of moisture on spontaneous combustion characteristics of lignite in piling state

In order to study the influence of moisture on the spontaneous combustion characteristics of low-rank coal in the piling state,based on the Frank-Kamenetskii theory,the open constant temperature heating testing method was applied to analyze the temperature rising process and critical spontaneous combustion ignition temperature of Baiyinhua lignite with different moisture contents(4%~23%).The influence of moisture on the spontaneous combustion characteristics of piling lignite under different coal particle sizes(0.5~5 mm)and coal pile volumes(1.25~10×10⁵ mm³)was studied.The results showed that the temperature rising laws of coal piles with different moisture contents were basically the same,and according to the temperature rising rate of the central point,the temperature rising process of coal sample could be divided into 4 dynamic stages.Under the same conditions of coal particle size and volume,the higher the moisture content,the higher the critical spontaneous combustion ignition temperature of coal sample,the longer the inhibition temperature rising time,and the greater the k value that characterized the intrinsic moisture evaporation intensity.Under the same conditions of moisture content and volume,the k value increased first and then decreased with the increase of particle size.Under the same conditions of moisture content and particle size,the larger the coal pile volume,the lower the critical spontaneous combustion ignition temperature,and the evaporation of moisture had the inhibition effect on the spontaneous combustion of coal piles with different volumes.