大佛寺井田4#煤润湿性研究

发布时间：2018-06-17 12:02

本文选题：大佛寺4~#煤 + 润湿性　；参考：《西安科技大学》2017年硕士论文

【摘要】：煤的润湿性是指煤吸附液体的一种能力,其润湿性的大小在生产生活中影响深远。例如在煤矿开采中产生的煤尘,用普通的水溶液喷雾降低效率差,原因在于煤的润湿性差,不易被水润湿。了解研究区煤的润湿性,以及找到可以改变水溶液的表面活性剂,对矿井生产有着很大的帮助。本文首先对研究区的煤质进行了研究。通过煤岩分析和工业分析结果,判定大佛寺4#煤为不黏煤;属于特低灰,中高级挥发烟煤;与相同等级的煤对比来看,大佛寺地区煤的水分和固定碳含量都比较高;元素分析发现大佛寺4#煤的碳元素含量(83.61%)相对同等级烟煤较高,氧元素含量为10.15%,氢元素含量为4.75%,氮元素含量为0.83%;镜煤中的碳元素含量(78.70%)小于暗煤的碳元素含量(83.16%),而其余氢元素、氧元素、氮元素的含量,镜煤都大于暗煤。其次,对煤的孔隙特征和比表面积特征进行研究。压汞实验和液氮吸附实验结果表明,大佛寺4#煤镜煤的比表面积大于暗煤的比表面,4#煤比表面积介于镜煤和暗煤之间;镜煤的孔容(孔体积)、平均孔喉半径(平均孔径)大于暗煤;与暗煤相比,镜煤的分选性更差,孔喉分布不均匀,整体偏粗,整体连通性不好;镜煤表面因碎屑限制,导致屑间孔连通性差;暗煤表面有高岭石出现,并具有相互垂直的张性裂隙,从而整体的连通质量优良;镜煤和暗煤的孔隙中都含有少量的墨水瓶孔(细瓶颈的孔)。最后对润湿性进行测定。煤水(煤与蒸馏水)界面的接触角测定结果表明,接触角从小到大依次为:暗煤面垂直层理面斜切层理面平行层理面镜煤面;非离子型表面活性剂6501在溶液浓度为1.6%时,大佛寺4#煤的平行层理,垂直层理,斜切层理,镜煤面和暗煤面的接触角基本降为原来的二分之一左右;润湿反转剂g502在溶液浓度为0.1%时,就可将接触角增加到原来的1.6倍左右;润湿效果并不会随着加入润湿剂溶液浓度的增加而线性增加,而是会在一定浓度范围内出现临界胶束浓度(CMC);因此,在考虑加入润湿剂之前,最好将浓度设计在临界胶束浓度之外,避免其影响。
[Abstract]:The wettability of coal refers to the ability of coal to adsorb liquid, and its wettability has a profound influence in production and life. For example, the coal dust produced in coal mining reduces the efficiency by common water spray, because the wettability of coal is poor, it is not easy to be wetted by water. Understanding the wettability of coal in the study area and finding surfactants that can change aqueous solution are of great help to mine production. In this paper, the coal quality in the study area is studied. According to the results of coal and rock analysis and industry analysis, it is determined that Dafosi-coal is non-caking coal, belongs to very low ash, middle and high grade volatile bituminous coal, and compared with the same grade coal, the moisture and fixed carbon content of coal in Dafosi area are relatively high. Element analysis showed that the content of carbon element in Dafusi coal (83.61) was higher than that of bituminous coal of the same grade, oxygen content was 10.15, hydrogen element content was 4.75m, nitrogen element content was 0.83.The carbon element content in mirror coal was 78.70%) lower than that in dark coal (83.161.The rest of hydrogen element was found to be lower than that of dark coal). The content of oxygen element, nitrogen element and mirror coal are higher than that of dark coal. Secondly, the pore characteristics and specific surface area characteristics of coal are studied. The results of mercury injection experiment and liquid nitrogen adsorption test show that the specific surface area of Dafusi coal mirror coal is larger than that of dark coal. The specific surface area of coal is between mirror coal and dark coal. The pore volume (pore volume) of vitrinite is larger than that of dark coal. Compared with dark coal, the separation of vitrinite is worse, the pore throat is uneven, the whole is coarse, and the overall connectivity is not good. The surface of mirror coal is restricted by debris. It leads to poor connectivity between cuttings, kaolinite appearing on the surface of dark coal, and vertical tensile fractures to each other, so that the overall quality of connectivity is good. The pores of mirror coal and dark coal contain a small amount of ink bottle holes (fine bottleneck holes). Finally, wettability was determined. The results of measurement of contact angle between coal and distilled water show that the contact angle is from small to large as follows: dark coal surface vertical bedding surface, oblique bedding surface, parallel stratified surface mirror surface, Nonionic surfactant 6501, when the solution concentration is 1.6, The parallel bedding, vertical bedding, oblique bedding, contact angle between mirror coal surface and dark coal surface are reduced to about 1/2, and the wetting reversal agent g502 is about 0.1 when the solution concentration is 0.1. The contact angle can be increased to about 1.6 times of the original, and the wetting effect will not increase linearly with the increase of the concentration of the wetting agent solution, but the critical micelle concentration will appear in a certain range of concentration; therefore, the wetting effect will not increase linearly with the increase of the concentration of the wetting agent solution. Before adding wetting agent, it is better to design the concentration beyond the critical micelle concentration to avoid its influence.
【学位授予单位】：西安科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD714

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