防治煤自燃的新型凝胶泡沫材料实验研究

发布时间：2018-04-20 00:12

  本文选题：煤炭自燃 + 凝胶泡沫　； 参考：《中国矿业大学》2017年硕士论文

【摘要】：煤炭自燃是煤炭开采过程中的主要灾害之一。在煤炭自燃防治技术中凝胶泡沫因其兼顾了凝胶和泡沫防灭火技术的优点被认为是一种较好的新型防灭火技术。当现有矿井有机或无机凝胶泡沫还存在发泡倍数低、耐温抗盐性弱、稳定性差的不足,为此论文开展了矿用防治煤炭自燃的凝胶泡沫材料的研究,从发泡剂、稳泡剂和促凝剂以及三者的复配方面针对性的开展了发泡性能、耐温抗盐性能、稳定性和阻化性等方面的研究,最后形成了一种倍数高、稳定性好的新型防治煤炭自燃的凝胶泡沫材料。论文主要开展成果如下:系统地对构成凝胶泡沫的复合起泡剂、稳泡剂、成胶体系进行了考察。采用打击法统一对八种单一起泡剂的起泡水平进行了测试,优选出较好的几种发泡剂后开展了正交实验,最终得到一种发泡倍数高、用量省的复配方案。在此基础上对复合起泡剂、常用泡沫剂进行了耐温和耐盐性能对比实验,对比得出复合起泡剂在两个方面都具有比较明显的优势。最后对稳泡物质进行选择,得到适合于复配发泡剂的最佳稳泡剂,其添加最佳添加量2.1%。根据物质成胶原理及其对泡沫的作用过程,考察了几种成胶体系,最终确定一种性能良好、时间可控(20min以内)的成胶体系J和G。研究了浓度、温度对胶凝时间的影响。研究表明,成胶体系的两种物质J和G的总浓度愈高,胶凝愈快,成胶时间愈短;同一浓度下,基液温度愈高,成胶愈快,时间愈少。并对其稳定性进行了考察。常温下,将其放置8h以后观察依然没有水出现;温度增高,凝胶泡沫受影响较小,普通泡沫显著减少,对比之下,凝胶泡沫优势明显。实验室研究最终得出,基液中复合泡沫剂总量4‰,成胶体系J和G的量各占3‰,稳泡剂添加量2.1%时,pH在7-9时,打击成泡沫凝胶的综合性能最好;同等条件下起泡能力是现有凝胶泡沫的1.2-1.4倍左右,泡沫半衰期达到98h以上。实验还从起泡倍数和温度两个方面对其粘性进行了考察。结果表明,粘度随倍数增长而先增后减;温度与其粘度存在负相关关系。最后对凝胶泡沫的的阻化性进行了考察。结果表明:凝胶泡沫可以明显减慢煤炭自燃进程,降低热释放速率,减少CO的释放量,经凝胶泡沫处理后的煤样,其交叉点温度比用水处理的煤样交叉点温度提高了20℃左右;温度超过100℃,要得到基本一样的CO释放量,凝胶泡沫浸泡样品比水处理样品的温度提高20℃左右。100℃时,凝胶泡沫的阻化率Eco为66.33%。
[Abstract]:Spontaneous combustion of coal is one of the main disasters in the process of coal mining. In the coal spontaneous combustion prevention and control technology, gel foam is considered to be a new type of fire prevention and extinguishing technology because of its advantages of both gel and foam fire prevention and extinguishing technology. When the existing mine organic or inorganic gel foam still has the shortcomings of low foaming ratio, weak temperature and salt resistance, and poor stability. Foaming stabilizers, coagulants and their combinations have been studied in the aspects of foaming performance, temperature and salt resistance, stability and resistance, etc. Finally, a kind of multiple was formed. A new type of gel foam material with good stability for preventing coal spontaneous combustion. The main achievements are as follows: the composite foaming agent, foam stabilizer and gelation system are systematically investigated. The foaming level of eight kinds of single foaming agents was tested by the method of striking, and the orthogonal experiment was carried out after the better foaming agents were selected. Finally, a compound scheme with high foaming multiple and low amount of foaming agent was obtained. On the basis of this, the comparison experiments on the properties of composite foaming agent and common foaming agent are carried out, and the results show that the composite foaming agent has obvious advantages in both aspects. Finally, the best foaming stabilizer suitable for the compound foaming agent was obtained by selecting the foaming stabilizer with the optimum addition amount of 2.1%. According to the principle of gelling and its action on foam, several kinds of gelatinizing systems were investigated, and a kind of gelling system J and G with good properties and controlled time within 20 min were determined. The effects of concentration and temperature on gelation time were studied. The results show that the higher the total concentration of J and G is, the faster the gelation time is and the shorter the gelation time is, the higher the temperature of the base solution is, the faster the gelation time is. Its stability was investigated. At room temperature, after 8 hours of storage, there was still no water. When the temperature increased, the gel foam was less affected, and the common foam was significantly reduced. In contrast, the gel foam had obvious advantage. The results of laboratory study show that the total amount of composite foaming agent in base solution is 4 鈥，

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