School of Chemical Machinery and Safety Engineering, Dalian University of Technology, Dalian, 116024, China.
School of Chemical Machinery and Safety Engineering, Dalian University of Technology, Dalian, 116024, China; China Academy of Safety Science and Technology, Beijing, 100012, China.
J Hazard Mater. 2019 Apr 15;368:797-810. doi: 10.1016/j.jhazmat.2019.02.001. Epub 2019 Feb 1.
The suppression effect of melamine cyanurate (MCA) and melamine polyphosphate (MPP) on the flame propagation of aluminum dust were studied experimentally. The results indicated that the concentration of MPP required to supress the aluminum dust explosion was lower than MCA. As the concentration of suppressant increased, the acceleration and the maximum flame speed extremely decreased, and the flame morphology became isolated spot flames. The MPP addition exerted a stronger suppression effect on the temperature of aluminum flame compared to MCA addition. Meanwhile, the mechanism of flame suppression was further investigated. Decomposition of MCA and MPP particles could absorb the heat released from the flame front. Scanning electron microscopy demonstrated that the gas phase reaction of aluminum particles was suppressed by MCA and MPP, resulting in a larger particle size of the explosion products. XRD results indicated that MCA and MPP did not react with aluminum. Gaseous products of suppressant decomposition altered flame chemistry by radically recombining O atom and reducing AlO, which resulted in less amount of heat release, lower flame speed and lower flame temperature.
三聚氰胺氰尿酸盐（MCA）和三聚氰胺聚磷酸盐（MPP）对铝粉尘火焰传播的抑制作用进行了实验研究。结果表明，抑制铝粉尘爆炸所需的 MPP 浓度低于 MCA。随着抑制剂浓度的增加，加速和最大火焰速度急剧下降，火焰形态变得孤立的点火焰。与 MCA 相比，MPP 的添加对铝火焰温度有更强的抑制作用。同时，进一步研究了火焰抑制的机理。MCA 和 MPP 颗粒的分解可以吸收火焰前沿释放的热量。扫描电子显微镜表明，MCA 和 MPP 抑制了铝颗粒的气相反应，导致爆炸产物的粒径更大。XRD 结果表明 MCA 和 MPP 与铝不发生反应。抑制剂分解的气态产物通过自由基重新组合 O 原子和还原 AlO，改变了火焰化学，导致释放的热量减少、火焰速度降低和火焰温度降低。
