Study on Gas Generation Characteristics of Magnesium, Aluminum and Aluminum-Magnesium Alloy Dusts upon Contact with Water

Metal dust reacts with water with the release of hydrogen and heat accumulation, which can easily form an explosive atmosphere in confined spaces and further trigger safety accidents. To investigate the regulation law of different factors on the gas generating reaction of metal dust upon contact with water, the HY21619 type water release gas tester was used to study the effects of water addition volume (10, 100 mL), dust mass (0.1, 0.5 g), dust type (magnesium powder, aluminum powder,aluminum-magnesium alloy powder) and particle size (20, 60, 100 μm) under a constant temperature of 20 ℃. Results reveal that dust mass and water dosage jointly regulated the gas generation process. The working condition of 0.5 g–10 mL had low heat capacity and obvious heat accumulation, presenting the optimal gas yield and gas production rate. Under identical experimental conditions, gas production capacity followed the order of magnesium powder > aluminum powder > aluminum-magnesium alloy powder, and the characteristics of the gas production rates of the three were different. Within the experimental particle size range, the total gas yield of aluminum-magnesium alloy powder increased first and then decreased with the rise of particle size, and the 60 μm alloy powder possessed the best gas generation efficiency. This study provides experimental evidence for implementing targeted control measures for industrial wet dust removal systems, and has significant theoretical significance for preventing accidents involving the explosion of metal dust upon contact with moisture.