瓦斯/煤尘复合爆炸是一个耦合了均相燃烧与异相燃烧的复杂过程，燃烧主控机制动态变化，爆炸机理更加复杂，导致其相比单相瓦斯或煤尘爆炸具有更高的爆炸敏感性和爆炸强度，严重制约着煤矿的安全生产。为了防治瓦斯/煤尘复合爆炸灾害，选取碳酸氢钠和碳酸钙两种惰性粉体，在20 L球型爆炸装置中开展了惰性粉体抑制瓦斯/煤尘复合爆炸实验。通过系统的改变瓦斯和煤尘浓度配比，对不同浓度惰性粉体作用下瓦斯/煤尘复合体系最大爆炸压力和最大爆炸压力上升速率变化规律进行分析，并对比分析不同惰性粉体抑制瓦斯/煤尘复合爆炸性能之间的区别和联系。研究结果表明，碳酸氢钠和碳酸钙对不同浓度配比的瓦斯/煤尘复合体系爆炸均具有抑制作用，其中碳酸氢钠不仅可以通过分解吸热、延缓煤尘热解、降低煤尘分解速率等物理抑制方式来抑制瓦斯/煤尘复合爆炸，还可以通过消耗爆炸反应的关键自由基的化学抑制方式来抑制瓦斯/煤尘复合爆炸，而碳酸钙只能以物理吸热的方式抑制爆炸，因此碳酸氢钠对瓦斯/煤尘复合体系爆炸的抑制效果优于碳酸钙，具体表现为碳酸氢钠可完全抑制所有工况，碳酸钙仅能完全抑制瓦斯浓度低于8%时的瓦斯/煤尘复合工况。另外，2种惰性粉体对瓦斯/煤尘复合体系爆炸压力的抑制效率随着体系中瓦斯浓度的提升先升高后降低，当瓦斯浓度为6%、煤尘浓度为100 g/m³时抑爆效率最高；对瓦斯/煤尘复合体系爆炸压升速率的抑制效率随着体系中瓦斯浓度的提升逐渐升高，对浓度为10%的纯瓦斯爆炸时抑爆效率最高。

Gas/coal dust composite explosion is a complex process that combines homogeneous and heterogeneous combustion. The combustion main control mechanism changes dynamically and the explosion mechanism is more complex, resulting in higher explosion sensitivity and explosion intensity compared to single-phase gas or coal dust explosion, which seriously restricts the safe production of coal mines. In order to prevent and control the gas/coal dust composite explosion disaster, two inert powders, sodium bicarbonate and calcium carbonate, are selected to conduct experiments on inert powder suppression of gas/coal dust composite explosions in a 20 L spherical explosion device. Based on the different concentration ratios of gas and coal dust, the inhibition effect of two inert powders on the maximum explosion pressure and the maximum explosion pressure rise rate of the gas/coal dust composite system are analyzed and compared, as well as the differences and connections between the inhibition effect of the two inert powders. And the inhibition efficiency and mechanism of the two inert powders on gas/coal dust composite explosions are reflected comprehensively. The research results indicate that sodium bicarbonate and calcium carbonate have an inhibitory effect on the explosion of gas/coal dust composite systems with different concentration ratios. Sodium bicarbonate can not only suppress the explosion of gas/coal dust composite by physical suppression methods such as decomposing heat absorption, delaying coal dust pyrolysis, and reducing coal dust decomposition rate, but also by chemical suppression methods that consume key free radicals in the explosion reaction, however, calcium carbonate can only suppress explosions through physical heat absorption, so the inhibitory effect of sodium bicarbonate on the explosion of gas/coal dust composite system is better than that of calcium carbonate. Specifically, sodium bicarbonate can completely suppress all working conditions, while calcium carbonate can only completely suppress the gas/coal dust composite working conditions when the gas concentration is below 8%. In addition, the suppression efficiency of two inert powders on the explosion pressure of the gas/coal dust composite system first increases and then decreases with the increase of gas concentration in the system. The suppression efficiency is highest when the gas concentration is 6% and the coal dust concentration is 100 g/m³; The suppression efficiency of the explosion pressure rise rate of the gas/coal dust composite system gradually increases with the increase of gas concentration in the system, and the suppression efficiency is highest for pure gas explosions with a concentration of 10%.