垃圾焚烧飞灰对瓦斯爆炸压力及火焰传播的抑制作用及机理研究

Study on the inhibition effect and mechanism of waste incineration fly ash on gas explosion pressure and flame propagation

通过自主搭建的可视化甲烷爆炸实验平台,在甲烷气体浓度为8%(富氧)、9.5%(当量)、12%(贫氧)的条件下,研究了不同质量的垃圾焚烧飞灰(FA)粉体对甲烷爆炸压力、火焰传播速度及火焰传播形态的影响。采用XRD分析、粒径分析、扫描电镜和热重分析对FA的成分、粒径、表面微观结构和热稳定性进行了分析,并结合物性表征分析了FA的抑爆机理。结果表明,FA对不同浓度甲烷爆炸均有较好的抑爆效果。本实验中,FA对于8%、9.5%、12%浓度甲烷最佳抑制的喷粉量分别为360、360、400 mg。FA粉体的加入,阻碍了甲烷爆炸火焰的发展传播,打乱了火焰形态,火焰强度明显减弱。FA的粒径较小,微观结构多孔,具有较大的比表面积和孔隙率,且具有较高的吸热性,其总质量损失为37.07%。FA粉体具有物理、化学双重抑爆性。

The effects of different mass of waste incineration fly ash(FA)powder on methane explosion pressure,flame propagation velocity and flame propagation morphology were studied by self-built visual methane explosion experimental platform under the conditions of methane gas concentration of 8%(oxygen-enriched),9.5%(equivalent)and 12%(oxygen-poor).The composition,particle size,surface microstructure and thermal stability of FA were analyzed by XRD,particle size analysis,scanning electron microscopy and thermogravimetric analysis.Combined with physical characterization,the explosion suppression mechanism of FA was analyzed.The results show that FA has a good explosion suppression effect on different concentrations of methane explosion.In this experiment,the best spraying amount of FA for 8%,9.5%,and 12%methane inhibition was 360 mg,360 mg,and 400 mg,respectively.The addition of FA powder hinders the development and propagation of methane explosion flame,disrupts the flame shape,and the flame intensity is obviously weakened.The FA has smaller particle size,porous microstructure,larger specific surface area and porosity,and higher heat absorption,with a total mass loss change of 37.07%.FA powder has dual explosion suppression properties of physics and chemistry.