【作者】 苏健；

【导师】 索红莉；

【作者基本信息】 北京工业大学 ， 材料工程（专业学位）， 2016， 硕士

【摘要】 煤炭资源是国民经济的命脉之一,时至今日,在我国能源消耗总量中煤炭消耗占比仍高达60%以上。我国地质结构复杂,频发的煤矿事故严重制约着煤炭行业的健康发展。化学防灭火材料作为一类煤矿用防灾减灾产品,以其优良的流动性、保水性、固结时间可控性等特点,在减轻采空区煤炭发火自燃、封堵巷道壁大型裂缝、解决矿井下透风、透水等问题上具有广阔的应用前景。本文研究了煤矿防灭火用水玻璃复合胶体灌浆材料(水玻璃/碳酸氢钠/膨润土体系)的最佳原料配比,并在此基础上,分别引入淀粉、纤维素、阴离子聚丙烯酰胺、阳离子聚丙烯酰胺等聚合物添加剂,研究了这4种添加剂对初始水玻璃复合胶体灌浆材料的凝胶时间、保水性能、体积收缩率、力学强度等性能的影响规律,并优选出复合胶体的最佳组分;通过采用红外光谱和XRD手段分析了复合胶体凝结过程中聚合物添加剂与原水玻璃复合胶体的复合机制及其作用。本文同时开发了一种适用于封堵煤矿井下大型透风裂缝的新型聚氨酯材料,该封堵材料由聚醚403、二苯基甲烷二异氰酸酯(MDI)、稀释剂、催化剂、交联剂等在室温反应制成,具有成本低廉、工艺简单、无毒害等优点。随后,通过正交实验法考察了各组分对封堵材料性能的影响,利用方差分析和极差分析确定了影响材料各项性能指标的关键因素。通过如上两部分的实验研究,得出以下重要结论:将聚合物作为改性添加剂引入传统水玻璃复合胶体灌浆材料中,聚合物添加剂并未直接参与凝胶反应,仅以物理混合形式存在于胶体结构中。最初在水中溶解的阳离子聚丙烯酰胺对后续加入的膨润土颗粒有明显的包覆效应,形成一种大颗粒物质,悬浮在体系中,不适合灌浆施工。当聚合物添加量超过0.2%时,体系粘度迅速上升,不适合实际输送和工程应用。与其它聚合物添加剂相比,在初始水玻璃复合胶体灌浆材料中添加0.1%~0.2%的纤维素添加剂后,灌浆材料的保水性能、抗压强度、体积收缩率、致密性等性能指标均有明显改善。采用“一步法”成功制备了一种新型聚氨酯封堵材料。聚醚403的用量是决定最终产品抗老化性能的主要因素,甲基膦酸二甲酯对产品的固结时间、反应放热量和抗压强度的影响起主导作用,二羟甲基丙酸作为交联剂主要影响最终产品的体积收缩率,三亚乙基二胺作为催化剂对固结时间和抗老化性能起着次级主导作用。为确保在煤矿实际应用中封堵材料具备低的放热量、高的抗老化性能、以及保持强度不变的情况下具有优良的发泡性,最终确定“25%的聚醚403、20%的甲基膦酸二甲酯(稀释剂、阻燃剂)、0.75%的二羟甲基丙酸(交联剂)和0.3%的三亚乙基二胺(催化剂)”为最优配比。通过前期参与煤矿喷涂堵漏风防灭火材料的工厂化生产、测试、设备选取、施工等一系列实践活动,在调研过程中发现存在一些问题,即单一喷涂堵漏风材料对大型裂隙无法达到密封效果,使采空区无法达到完全的密闭堵漏。本论文提出了将改性水玻璃复合胶体材料、新型聚氨酯封堵材料与喷涂堵漏风材料相互配合使用的施工方案:改性水玻璃复合胶体材料覆盖于采空区松散煤体表面,达到阻氧、降温的双重效果;新型聚氨酯封堵材料压注于大型煤岩裂缝中,与原喷涂堵漏风材料相配合,达到完全堵漏风的目的,并且通过聚氨酯固结体的高强度以及与煤岩的结合性,防止煤矿震动产生新的透风裂隙。总之,本论文通过引入聚合物添加剂,成功制备了一种改进型水玻璃复合胶体灌浆材料;针对矿井下大型透风裂缝,成功开发了一种新型聚氨酯封堵材料,并通过正交实验法确定了最优的原料配方;本研究对煤矿井下新型防灭火材料的开发和应用提供了重要的实验依据。更多还原

【Abstract】 Coal resources are one of the lifeblood of the national economy. Now coal resources account for more than 60% in China’s total energy consumption. Due to China’s complex geological structure, the frequent occurrence of coal mine accidents, which restricts the healthy development of the coal industry. As a kind of coal mine disaster prevention products, chemical fire prevention materials have broad application prospects, It is widely used in reducing the mined area of coal spontaneous combustion, plugging the tunnel wall of large cracks, solving the problems of ventilation and water inrush, due to its excellent mobility, water retention, consolidation time controllability and so on.In this paper, the best ratio of the flame retardant water glass composite colloidal grouting material was studied. On the basis of the original raw materials, this paper introduced four kinds of polymer additives which are starch, cellulose, anionic polyacrylamide, cationic polyacrylamide, and according to the study of the effects of four kinds of additives on the gel time, water retention property, volume shrinkage, crack resistance and mechanical strength of raw water glass composite, the composition of the composite colloid was optimized. By means of infrared analysis and XRD, the composite mechanism, the effect of polymer additives and the raw water glass composite colloids were analyzed.This paper also studied a kind of polyurethane material that used for closure large cracks and wall ventilation in coal mine. The material was synthesized by polyether 403, MDI, diluent, catalyst, and crosslinking agent at room temperature. It has the bright features due to its of low cost, simple process, no toxic side effect, etc. Subsequently, the effects of the components on the performance of the sealing materials were investigated by orthogonal experiment. The key factors affecting the performance of the materials were determined by means of variance analysis and range analysis.Through the above two parts of the experimental study, the following important conclusions are drawn:Polymer modified additives were introduced into the water glass composite colloidal system. It showed that four kinds of polymer additives did not directly participate in the chemical reaction but existed as the form of dopant. The cationic polyacrylamide dissolved in water has obvious coating effect on the subsequent addition of bentonite particles, forming a kind of large granular material, which is not suitable for grouting construction. When the polymer content is greater than 0.2%, because of the rapid increasing of system viscosity, it is not suitable for actual transportation and engineering applications. Compared to the water glass composite colloid with other additives and the original sample, the cellulose additives from 0.1% to 0.2% have a greater advantage in water retention properties, consolidation strength, volume shrinkage, density and other properties."One step method" was used in the synthesis process of polyurethane sealing material. The amount of polyether 403 mainly affects the aging resistance of the final product; the effect of Dimethyl Methylphosphonate(DMMP) is the leading role on the consolidation time, the heat of reaction and the compressive strength of the product. As the crosslinking agent, Dimethylol Propionic Acid(DPA) mainly affects the volume shrinkage rate of the final product. The triethylenediamine play a secondary leading role in the consolidation time and aging mass loss rate. In the practical application of coal mine, considering the requirements of low heat release, excellent aging resistance and maintaining the strength of the same situation with excellent foaming, it should take 25% of polyether 403, 20% DMMP, 0.75% of DPA, 0.3% of triethylenediamine as the optimal formulation.By participating in the factory production, testing, construction of the coal mine fire prevention and extinguishing spraying plugging material, we found that some problems exist, including that single spraying plugging wind material can’t reach the sealing effect for large fracture, leading to that the mined-out area can’t be effectively confined. This paper put forward a kind of construction plan which is to use water glass compound gel material, new type polyurethane sealing material together with the spray wind plugging material. The modified water glass compound colloid material will be covered on the surface of loose coal in mined-out area, achieving the dual effect of oxygen resistance and cooling. The new type polyurethane sealing material will be filled in large cracks in coal and rock. Through the common use of original spray plugging wind material, it was expected to achieve the effect of complete plugging. Relying on the high strength of polyurethane and the combination of polyurethane and coal, meanwhile to prevent new drafty cracks generation because of the vibrations of coal mine.In summary, the modified water glass composite colloid grouting materials were prepared successfully through the introduction of polymer additives. In order to plugging the large cracks in coal mine, a kind of polyurethane material was successful developed, and the optimum formula of raw material was determined by orthogonal experiment method. This study provides an important experimental basis for the development and application of new type of extinguishing and preventing materials in coal mine.更多还原