瓦斯爆炸是危害最大的矿井灾害之一，严重威胁着井下工作人员的生命安全，制约矿井生产的发展。井下的生产环境极其复杂，事故的随机性和偶然性表现突出，给事故预防带来极大的困难，所以利用有效的技术手段进行事故控制是十分必要的，尤其针对瓦斯爆炸这类难预防、危害严重的事故进行控制具有重要的现实意义。但目前国内外众多瓦斯爆炸控制技术研究成果中，还没有一项技术能在爆炸三要素同时具备的情况下有效控制矿井瓦斯混合气体不发生爆炸。所以，开发和研究新型抑爆材料对瓦斯爆炸灾害的防治具有重要意义。 本文从粉体抑爆机理及抑爆剂基本性能出发，分析了超细粉体抑爆剂的可行性及特点，并自行搭建了20L近球形抑爆实验装置，选取二氧化硅和硅藻土粉体作为瓦斯抑爆剂，进行了系列实验。首先，测试了宏观静止和湍流两种状态下烷-空混合气体的爆炸特性参数，得出初始湍流对瓦斯爆炸具有明显促进作用的重要结论，同时分析了湍流对爆炸特性参数的影响规律，为正确处理粉体抑爆实验中材料施放的诱导湍流问题提供了指导；其次，利用爆炸极限、爆炸压力等特性参数表征抑爆效果，探讨了粉体抑爆剂抑爆效能的测试方法，测试并对比了二氧化硅和硅藻土超细粉体抑制烷-空预混气爆炸的效果，同时研究了粉体抑爆剂本身特性和施放因素等对其抑爆效果的影响规律。 实验结果表明：主要成分为SiO2的超细粉体在防爆和抑制初始爆炸方面都具有一定的效果。其中，抑爆效果由大到小依次为纳米SiO2、微米硅藻土、微米SiO2，粉体粒度越小抑爆效果越好，且同数量级粒度下，多孔硅藻土的抑爆效果更好。添加超细粉体后，甲烷爆炸极限浓度范围变窄，爆炸压力降低，但反应容器内粉体浓度适量才具有明显效果，且粉体喷洒后，仅在固定时间范围内抑爆效果较明显。粉体抑爆实验系统的搭建及超细粉体抑爆系列实验研究为粉体抑爆剂施放工艺设计和抑爆性能优化提供了一定的指导，为发展超细粉体抑爆剂奠定了一定的基础。

Gas explosion, one of the most serious mine disasters, are serious endangering the lives of mining workers, and restraining the mining production. The complex underground work environment and the randomness of accidents bring about great difficulties to accident prevention, and therefore it is very necessary to control accidents with effective technologies, especially controlling gas explosion which will cause serious consequences and is less easily preventable has practical significance. At present, there is not any technique which can efficiently stop the gas explosion whether three explosion elements have been met. So it is greatly important to research and develop the new explosion suppressant for gas explosion disaster prevention and mitigation. Based on the mechanism of powder suppressing explosion and some basic properties of explosion suppressant, the feasibility analysis and characteristic analysis of ultrafine particles as explosion suppressant were completed, and a series of experiments of powder suppressing explosion were carried out using a 20L spherical device (steel container) builded independently in this paper. Firstly, the explosion basic parameters of static and turbulent premixed methane-air were tested, to verify the feasibility of the experiment device, to show that the initial turbulence will promote gas explosion and analyse the effect of turbulence upon gas explosion to provide guidance for solving turbulence problem resulted from the powder suppressant insufflation in experiments of powder suppressing explosion; Secondly, the effect of ultrafine silicon dioxide and diatomite powder suppressing gas explosion was measured and compared with the method using explosion property parameters tested as characterization of suppressant effectiveness and efficiency, and researched the law of the effect of suppressant powder nature and discharge process factors upon explosion suppression effect . The results of this research show that the ultrafine powder in which primary component is silicon dioxide is effective for explosion prevention and initial explosion suppression. The explosion suppression effect of nometer silicon dioxide and micron diatomite is more obvious than micron silicon dioxide, and the effect of nanometer silicon dioxide is the best. After insufflating ultrafine powder, the explosion limit scope of metha turns narrow, and explosion pressure reduces , but the effect is clear when the powder density proper in reaction container and only during the fixed period of time. The built experiment system of powder suppressing explosion and related experiments provide guidance for the design of suppressant powder discharge process and optimizing effectiveness of suppressant, and lay a foundation for the development of the ultrafine powder suppressant.