管道相连泄爆容器中粉尘爆炸的实验研究

Experimental research on dusts explosion in interconnected vented vessels

采用管道相连容器进行了工业规模的粉尘爆炸实验,目的是研究粮食粉尘在管道相连的加工和输送工业设备中发生粉尘爆炸时火焰和爆炸压力的传播过程及粉尘的Kst值对爆炸的影响。实验装置为一个气力输送系统,由两个不同体积的容器通过管道连接构成。采用粮食工业上具有代表性的两类粉尘进行了粉尘爆炸测试,爆炸从一个容器中通过管道传播到另一个容器中并引发了随后的二次爆炸,测试了不同位置的火焰和压力信号。实验结果表明:即使在起爆容器采取了泄爆措施,管道中没有粉尘喷入的情况下,粉尘爆炸火焰也可沿管道传播达30m并引发二次爆炸;随着粉尘爆炸指数的增大,初始爆炸的猛烈程度增强,火焰传播速度加快,二次爆炸的猛烈程度也随之增强。

Industrial scale dust explosion experiments were conducted in interconnected vessels.The purpose of the work is to investigate the propagating course of flame and pressure wave of grain dust explosions in intercon nected powder processing and transporting industrial plants and the influence of dusts＇ Kst value on explosion.Experimental plant is a pneumatic conveying system consisting of two vessels with different volume connecting via a long pipe.Explosion tests were carried out by using two representative types of grain dusts,explosion transferred from one vessel into the other vessel through pipe and subsequently induced secondary explosion.Time history of pressure and flame were measured at different locations.The experimental results show that,even when primary vessel was vented and no dust presented in pipe,explosion induced flame can still propagate through pipe up to 30m and induced secondary explosion,with increasing dust explosion index,the explosion extent become more violent and flame propagating velocity increase,secondary explosion become more violent too.