Abstract: The characteristics and application of the branched chain explosion of hydrocracking hydrogenation recycle gas and the relevant combustible gases were systematically studied. The explosive limits of concentration, explosive morphology, explosive waveforms and their influence factors were investigated. From the different kinds of explosive morphology and its pressure waveforms, a new idea on compartmentalization of explosive morphology for the hydrocracking hydrogenation recycle gas was introduced.Within the explosive limits, four kinds of explosive morphology (cold flame, deflagration，detonation，and transition from deflagration to detonation) could be compartmentalized and seven explosive zones (lower cold flame zone, lower deflagration zone, lower deflagration transformed into detonation zone, detonation zone，upper deflagration transformed into detonation, upper deflagration zone and upper cold flame zone) could be classified. The different mechanisms for developing the pressure waves of the explosive morphology were explored. Such knowledge is valuable for further studying the relevant system of branched-chain explosion and developing the theory of branched-chain explosion.The minimum ignition energy, the maximum experimental safe gaps, the degree of explosion danger and other
explosion characteristics were experimentally determined. This paper also introduces the concept of ‘key components’ and pointes out that it is the key components of H2 and oxidant O2 that ignite explosion for the system consideres here.The references and methods for developing the explosion-proof safety guidelines were proposed. The results will be of significance in preventing accidents caused by mixture gas branched-chain explosion, giving directions to designing explosion-proof electric equipment and fire arresters, supervising the application of the concepts of branched-chain burning and branched-chain explosion to practice.

Key words: 支链爆炸, 浓度爆炸极限, 爆炸形态, 爆炸波形, 防爆安全指标

摘要： 对加氢裂化循环气与相关可燃性气体支链爆炸的特性及其应用进行了系统的研究.探索了浓度爆炸极限、爆炸形态与波形及其影响因素;根据爆炸形态与波形的不同，提出了对加氢裂化循环气爆炸形态科学区划的新理念;在爆炸极限内，可以进一步区划4种爆炸形态(冷焰、爆燃、爆轰、爆燃向爆轰转化)，与7个爆炸区域（上、下冷焰区，上、下爆燃区，上、下爆燃向爆轰转化区，爆轰区），并探讨了不同爆炸形态压力波的发展机制.对进一步研究相关的多元支链爆炸体系，促进多元支链爆炸理论的发展，具有一定的理论价值.实验测得了爆炸危险度、火焰蔓延极限、最小点火能等特性参数;引进了“关键组分”的概念，指出加氢裂化循环气的多元体系，引发爆炸的物质是关键组分H₂和氧化剂O₂;探讨了制订防爆安全指标的依据与方法.对于预防混合气体支链爆炸事故的发生、指导防爆电气设备与阻火器的设计、指导支链燃烧与支链爆炸的实践，具有参考价值.

关键词: 支链爆炸, 浓度爆炸极限, 爆炸形态, 爆炸波形, 防爆安全指标