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论文类型：期刊论文

发表时间：2020-03-15

发表刊物：JOURNAL OF HAZARDOUS MATERIALS

收录刊物：PubMed、EI、SCIE

卷号：386

页面范围：121648

ISSN号：0304-3894

关键字：Aluminum dust explosions; Explosion suppression; Detailed suppression mechanism; Surface kinetics

摘要：The suppression mechanism of melamine polyphosphate (MPP) and melamine cyanurate (MCA) for Al dust explosions is investigated experimentally and computationally. Results show that depending on the concentration of suppressants, the addition of MCA and MPP promotes or suppresses Al dust explosion. For high additive concentration, large agglomerated residues are generated, and condensed phase residues may contain Al particles, MCA or MPP. The chemical composition of condensed phase residues of Al/MCA mixture explosion is mainly Al2O3 and the high boiling products of MEL decomposition (mainly C- and N-containing species). The explosion residues of Al/MPP mixture are composed of Al2O3, high boiling products of MEL decomposition and condensed phosphates. To understand the reasons for pressure enhancement and explosion suppression, a kinetic model considering both gas and surface chemistry of Al particles combustion is developed. The simulations indicate that the high pressure rise is caused by the extra heat released from the exothermic reactions of suppressants and the increase of gas phase products. MPP and MCA can suppress surface reaction by decreasing Al (L) site fraction. Additionally, the vaporization rate of Al particles and the diffusion rate of oxidizers close to the droplet surface are reduced by MPP and MCA addition.