Explosion Characteristics and Influential Factors of Coal dust/sodium Chlorate Mixture on Basis of an Explosion Accident in China

In the paper, explosion characteristics of coal dust in the presence of strong oxidant were studied using a 20-L spherical vessel, and the influential factors, including air relative humidity, ambient temperature and combustible gas of hybrid explosion were investigated. Results showed that sodium chlorate dust could increase the explosion severity of coal dust to some extent, while the power of hybrid explosion was weakened for the increasing content of its decomposition product. The explosibility of blend samples both presented a trend of increasing at low air relative humidity and then deceasing at high air relative humidity. The explosion severities of blend samples were strengthened for the increasing ambient temperature in a certain range. CH4 had a promotion effect on the explosion performance of Blend A, and P-max and (dP/dt)(max) values of Blend A dust explosion, respectively, increased by 56.1% and 200% with the addition of CH4. While the explosion severity of Blend B was promoted for adding a small amount of CH4, but suppressed for a high CH4 content. The experimental results have guiding significance for the risk assessment of coexistence of coal dust and hazardous chemicals, especially in confined space.