防治煤炭自燃的三相泡沫理论与技术研究  

Research on Theory and Technology of Three-Phase-Foam for Preventing Spontaneous Combustion of Coal

作　　者：秦波涛[1] 

机构地区：[1]中国矿业大学安全工程学院煤炭资源与安全开采国家重点实验室,江苏徐州221008

出　　处：《中国矿业大学学报》2008年第4期585-586,共2页Journal of China University of Mining & Technology

摘　　要：针对目前我国煤矿防灭火技术和手段存在不足,特别是针对大范围采空区或巷道高冒火灾、采空区隐蔽火源及高位火源、综放及俯采工作面煤炭自燃防治的难题,提出了由粉煤灰(黄泥)、氮气和水组成的三相泡沫防灭火新技术,该技术可以利用煤矿已有的注浆系统将三相泡沫注入采空区并形成覆盖面广、可向高冒区堆积的泡沫体,能较好地充填采空区或高冒区,有效扑灭火灾.针对固体不燃物(粉煤灰、黄泥)、水和氮气三相介质的特性,成功研制出了使浆液具有较高发泡倍数和较长稳定时间的三相泡沫发泡剂.应用浮选动力学、表面化学、物理化学、热力学和流体机械等理论,较系统地提出了三相泡沫的形成机理.根据三相泡沫的特点,发明了三相泡沫发泡器。应用流体力学理论,建立了发泡器喉部至扩散段区域负压大小和浆液流量的方程关系式,并通过CFD流体力学软件模拟了三相泡沫发泡器内不同扩散角度下管内静压和浆液流速的分布状况,得出了扩散角为60°时的压力分布和流速是形成三相泡沫的最佳条件.开展了三相泡沫发泡剂溶液阻止煤自燃的试验研究,结果表明:三相泡沫发泡剂溶液对煤自燃的阻化效果显著,能有效地减缓煤的氧化放热速率,抑制煤温度的升高,同时也有效地抑制CO的释放量,是很好的防止煤炭自燃的阻化剂;三相泡沫的灭火性能试验表明,三相泡沫可在较致密的多孔介质中不同方向流动,渗透性强,流动范围广,可扑灭较大范围区域内的高位火源和隐蔽地点的火源.三相泡沫流变特性研究表明,含黄泥或粉煤灰颗粒的三相泡沫属于屈服假塑性非牛顿流体;试验考察了发泡倍数、浆液浓度、外界温度及气体介质对三相泡沫黏度的影响;建立了三相泡沫在水平管道中流动的数学模型,确定了三相泡沫发泡器在井巷中合理的安装位置;建立了三相泡�It is difficult to deal with the fire in large area goaf, the top or undeterminated fire in goaf and spontaneous combustion of coal in slope and downward working face. Based on this, a new technology of three-phase-foam, which composed of fly ash or mud, nitrogen gas and water, was developed for mine fire control. The new technology grouts the three-phase-foam into the goaf covering wider area and accumulating to the high caving area using the existing grouting system. So the fire can be put out efficiently. According to the analysis on chemical elements, microstructure, phase compositions and water quality, a new foaming agent with high foam expansion and long stable time was developed successfully. The forming mechanism of three-phase-foam was obtained with the principles of thermodynamics, chemistry and hydrokinetics. Based on the characteristics of three-phase-foam, the foaming generator with high foam expansion was designed. Equation between flux of slurry and relative minus pressure in the distance of laryngeal to diffused segment was set up by Bernoulli＇s equation. Distributions of velocity and press in tube with different diffused angles were simulated by CFD software. The flow rate and pressure under 60°diffusion angle meet the condition of forming three-phase-foam well. Experiments were done to research the characteristics of three-phase-foam in preventing spontaneous combustion of coal. The results show that the preventing effect of three-phasefoam is remarkable. It can effectively depress the oxidation heat release rate, control the temperature of coal to rise and restrain releasing quantity of CO. The extinguishing experiments of three-phase-foam show that it can flow at different azimuth in compact porous media with strong penetrability and wide range, and can extinguish the top or undeterminated fire in goaf. The rheological properties of three-phase-foam with fly ash or mud were studied. It exhibits non-Newtonian behaviour and a characteristic of pseudo-plastic material. RheologicaI properties

关 键 词：矿井火灾 煤炭自燃 三相泡沫 发泡剂 发泡器 

分 类 号：TD753.4[矿业工程—矿井通风与安全]