长期水浸对不同烟煤自燃参数与微观特性影响的实验研究

发布时间：2018-09-17 19:06

【摘要】：为了更好地防治水浸采空区的自燃火灾,利用DSC,FTIR,XRD等手段研究长期水浸前后补连塔烟煤与西曲烟煤的微观结构及自燃特性变化。发现经过30~90 d的水浸后,煤样在低温氧化过程中的活化能降低1.73~7.94 k J/mol,且放热量增大,煤中—CH_2—,—OH,C—O等活性结构吸收峰变化显著。此外,水浸后煤中Si O2含量大幅降低,煤表面Si,Na,Ca,Fe,S等元素富集,矿物质的析出致使煤体膨胀、破碎,大于10 nm的孔隙增加4.61%~17.35%,提高了煤中氧扩散速率;同时,由于水浸后煤的抗拉强度最低降至0.192~0.495 MPa,完整的块煤更容易破碎,加剧了采空区自燃风险。煤中矿物组分与含量的差异导致水浸后补连塔与西曲煤自燃特性变化的幅度也有所不同。
[Abstract]:In order to prevent and cure spontaneous fire in flooded goaf, the changes of microstructure and spontaneous combustion characteristics of Bulianta bituminous coal and Xiqu bituminous coal before and after long-term flooding were studied by means of DSC,FTIR,XRD. It is found that after 30 ~ 90 days of water leaching, the activation energy of coal samples decreases by 1.73 ~ 7.94 k / mol / mol during low temperature oxidation, and the heat emission increases, and the absorption peak of active structures such as -Ch _ 2-T _ (2-O) -OHH _ (C-O) in coal varies significantly. In addition, the content of Si O 2 in coal decreases significantly after water leaching, and the Si,Na,Ca,Fe,S and other elements on the coal surface are enriched, and the precipitates of minerals lead to the expansion and fragmentation of the coal body. The porosity greater than 10 nm increases by 4.61% and 17.35%, which increases the diffusion rate of oxygen in the coal. Due to the lowest tensile strength of coal after water leaching to 0.1922 ~ 0.495 MPa, intact block coal is easier to be broken, which increases the risk of spontaneous combustion in goaf. The difference of mineral composition and content in coal leads to the change of spontaneous combustion characteristics of Bulian tower and Xiqu coal.
【作者单位】：太原理工大学矿业工程学院;
【基金】：国家自然科学基金资助项目(51604185) 山西省回国留学人员科研基金资助项目(2015-37)
【分类号】：TD752.2

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